John L Koprowski

Interests

Research

Wildlife conservation and management with special focus on rare species, population and behavioral ecology, and international conservation

Teaching

Active- and experiential learning in conservation biology, ecology and wildlife biology

Courses

Scholarly Contributions

Books

• Jo, Y. S., Baccus, J., & Koprowski, J. L. (2018). Mammals of Korea. Seoul, Korea: National Institute of Biological Resources.
• Koprowski, J. L., & Krausman, P. R. (2019). International Wildlife Management. Baltimore: Johns Hopkins University Press.

Chapters

• Koprowski, J. L., Gonzalez-Maya, J. F., Zárrate-Charry, D. A., Sharma, U. R., & Spencer, C. (2019). Local approaches and community-based conservation. In International Wildlife Management. Baltimore: Johns Hopkins University Press.
• Koprowski, J. L., Krausman, P. R., & Wang, D. (2019). International wildlife: a global perspective.. In International Wildlife Management. Baltimore: Johns Hopkins University Press.
• Koprowski, J. L. (2017). Introduction to the Andean Bear. In El Oso Andino en el Macizo de Chingaza(pp ii). Bogota: Parques Nacionales Naturales de Colombia.
• Koprowski, J. L., & Munroe, K. E. (2017). The professional interview: preparing for success. In Becoming a wildlife professional(pp 158-165). Baltimore: Johns Hopkins University Press.
• Koprowski, J. L., Derbridge, J. J., & Pepper, H. W. (2016). Economic damage by invasive grey squirrels in Europe. In In book: The Grey Squirrel: Ecology and Management of an Invasive Species in Europe, Chapter 20, Editors: Craig M Shuttleworth, Peter W Lurz, John Gurnell(pp 393-405). European Squirrel Initiative,.
• Koprowski, J. L., Goldstein, E. A., Mendes, C., & Bennett, K. (2016). Family Sciuridae (Tree, flying and ground squirrels, chipmunks, marmots and prairie dogs). In Handbook of Mammals of the World: Lagamorphs and Rodents (Vol 6), Don E. Wilson, Thomas E. Lacher, Jr, Russell A. Mittermeier (eds)(pp 648-837). Barcelona: Lynx Edicions.
• Koprowski, J. L., Munroe, K. E., & Edelman, A. J. (2016). Gray not grey: the ecology of Sciurus carolinensis in their native range in North America. In The Grey Squirrel: Ecology & Management of an Invasive Species in Europe, Chapter: 1, Publisher:Editors: Shuttleworth Craig, Lurz Peter, Gurnell John(pp 1-18). European Squirrel Initiative,.
• Koprowski, J. L., Shuttleworth, C., & Selonen, V. (2016). Grey squirrel nesting ecology and the use of nest sites in European population management. In The Grey Squirrels: Ecology & Management of an Invasive Species in Europe, Chapter 18, Editors: Shuttleworth Craig, Lurz Peter, Gurnell John(pp 349-368). European Squirrel Initiative.
• Koprowski, J. L. (2015). Lurz, P.W.W., S. Bertolino, J.L. Koprowski, P. Willis, M. Tonkin, J. Gurnell, 2015. Squirrel monitoring: snapshots of population presence and trends.. In Ecology, Conservation & Management of Red Squirrels in Europe,(pp In: Shuttleworth, C., Lurz, P., Hayward, M. (eds.)). Edinburgh: University of Edinburgh.
• Koprowski, J. L., & Fairbanks, W. S. (2013). Wildlife Behavior. In Cain, J.,Krausman, P.R. (eds.) Wildlife Management: Contemporary Principles and Practices,(p. 14). Baltimore: Johns Hopkins University Press.

Journals/Publications

• Abercrombie, S. T., Koprowski, J. L., Nichols, M. H., & Fehmi, J. S. (2019). Native lagomorphs suppress grass establishment in a shrub-encroached, semiarid grassland. ECOLOGY AND EVOLUTION, 9(1), 307-317.
• Altemus, M. M., Koprowski, J. L., & Brown, D. E. (2019). Seasonal changes in the home range of the antelope jackrabbit (Lepus alleni). MAMMAL STUDY, 44(2), 121-127.
• Chen, H. L., & Koprowski, J. L. (2019). Can we use body size and road characteristics to anticipate barrier effects of roads in mammals? A meta-analysis. HYSTRIX-ITALIAN JOURNAL OF MAMMALOGY, 30(1), 1-7.
• Derbridge, J. J., & Koprowski, J. L. (2019). Experimental removals reveal dietary niche partitioning facilitates coexistence between native and introduced species. ECOLOGY AND EVOLUTION, 9(7), 4065-4077.
• Granillo, K., Hoagland, S., Kessler, W., Koprowski, J. L., & Zummo-Strong, K. (2019). Moving forward: how do we change the culture of sexual harassment against women. Wildlife Professional 13:37-40.. Wildlife Professional, 13, 37-40.
• Mendes, C. P., Koprowski, J. L., & Galetti, M. (2019). NEOSQUIRREL: a data set of ecological knowledge on Neotropical squirrels. MAMMAL REVIEW, 49(3), 210-225.
• Nigenda-Morales, S. F., Gompper, M. E., Valenzuela-Galvan, D., Lay, A. R., Kapheim, K. M., Hass, C., Booth-Binczik, S. D., Binczik, G. A., Hirsch, B. T., Mccolgin, M., Koprowski, J. L., McFadden, K., Wayne, R. K., & Koepfli, K. (2019). Phylogeographic and diversification patterns of the white-nosed coati (Nasua narica): Evidence for south-to-north colonization of North America. MOLECULAR PHYLOGENETICS AND EVOLUTION, 131, 149-163.
• Pereira Mendes, C., & Koprowski, J. (2019). Does caching strategy vary with microclimate in endangered Mt. Graham red squirrels?. PloS one, 14(11), e0224947.
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  Food hoarding is a common behavior used by a variety of animals to cope with periods of low food availability. At the retreating edge of species' distribution, the stressful environment and unfavourable climate conditions may impose severe costs on hoarding behavior. Since relict populations are hotspots for evolution and adaptation, and considering that food hoarding behavior has a strong evolutionary basis, we decided to evaluate the occurrence of behavioral variability in the amount of food cached by the endangered Mount Graham red squirrel (Tamiasciurus fremonti grahamensis). We tested the variation in cache size in response to microclimate, soil relief, vegetation, food availability and squirrel sex. The number of pits excavated by squirrels to cache cones was used as a proxy of cache size and was affected by mountain slope aspect and density of trees. More pits were excavated in the northeast facing slopes. The density of trees negatively affects the cache volume on southwest slopes, but not on northeast slopes. The sex of the resident squirrel also affects the number of pits in the squirrel midden, with males excavating 47% more pits than females. Males and females also presented different responses to the mountain slope aspect, with females excavating more pits on northeastern slopes than on southwestern slopes, whereas male cache size did not vary with the slope aspect. Finally, the squirrel's caching behavior did not vary in response to midden microclimate variation, a result with possible implications for the survival of the Mt Graham red squirrels, given the predicted temperature increases in the region due to climate change.
• Goldstein, E. A., Merrick, M. J., & Koprowski, J. L. (2018). Low survival, high predation pressure present conservation challenges for an endangered endemic forest mammal. BIOLOGICAL CONSERVATION, 221, 67-77.
• Hale, S. L., & Koprowski, J. L. (2018). Ecosystem-level effects of keystone species reintroduction: a literature review. RESTORATION ECOLOGY, 26(3), 439-445.
• Jo, Y., Baccus, J. T., & Koprowski, J. L. (2018). Mammals of Korea: a review of their taxonomy, distribution and conservation status. ZOOTAXA, 4522(1), 1-216.
• Masoudi, A., Koprowski, J. L., Bhattarai, U. R., & Wang, D. (2018). Elevational distribution and morphological attributes of the entomopathogenic fungi from forests of the Qinling Mountains in China. APPLIED MICROBIOLOGY AND BIOTECHNOLOGY, 102(3), 1483-1499.
• McColgin, M. E., Koprowski, J. L., & Waser, P. M. (2018). White-nosed coatis in Arizona: tropical carnivores in a temperate environment. JOURNAL OF MAMMALOGY, 99(1), 64-74.
• Brady, M. J., Koprowski, J. L., Gwinn, R. N., Jo, Y., & Young, K. (2017). Eastern fox squirrel (Sciurus niger, Linnaeus 1758) introduction to the Sonoran Desert. MAMMALIA, 81(2), 221-223.
• Goldstein, E. A., Merrick, M. J., & Koprowski, J. L. (2017). Functional semelparity drives population dynamics and endangers a peripheral population. BIOLOGICAL CONSERVATION, 205, 52-59.
• Goldstein, E. A., Merrick, M. J., & Koprowski, J. L. (2017). Functional semelparity drives population dynamics and endangers a peripheral population.. Biological Conservation, 205, 52-59.
• Ketcham, S. L., Koprowski, J. L., & Falk, D. A. (2017). Differential response of native Arizona gray squirrels and introduced Abert's squirrels to a mosaic of burn severities. MAMMAL STUDY, 42(4), 247-258.
• Kilanowski, A. L., & Koprowski, J. L. (2017). Female-biased sexual size dimorphism: ontogeny, seasonality, and fecundity of the cliff chipmunk (Tamias dorsalis). JOURNAL OF MAMMALOGY, 98(1), 204-210.
• Koprowski, J. L., & Gwinn, R. N. (2017). Differential response to fire by an introduced and an endemic species complicates endangered species conservation. Hystrix, 28, 1-7.
• Koprowski, J. L., & Palmer, R. R. (2017). Sciurus sanborni. Mammalian Species, 49(952), 93-96.
• Koprowski, J. L., Brady, M., Gwinn, R. N., Jo, Y. S., & Young, K. (2017). Eastern fox squirrel (Sciurus niger, Linnaeus 1758) introduction to the Sonoran Desert. Mammalia.
• Koprowski, J. L., Montes, A., Timm, R., Lara, N. R., & Palmer, G. H. (2017). Sciurus aureogaster. Mammalian Species, 41(951), 81-92. doi:10.1093/mspecies/sex009
• Merrick, M. J., & Koprowski, J. L. (2017). Altered natal dispersal at the range periphery: The role of behavior, resources, and maternal condition. ECOLOGY AND EVOLUTION, 7(1), 58-72.
• Merrick, M. J., & Koprowski, J. L. (2017). Circuit theory to estimate natal dispersal routes and functional landscape connectivity for an endangered small mammal. LANDSCAPE ECOLOGY, 32(6), 1163-1179.
• Merrick, M. J., & Koprowski, J. L. (2017). Should we consider individual behavior differences in applied wildlife conservation studies?. BIOLOGICAL CONSERVATION, 209, 34-44.
• Chen, H. L., & Koprowski, J. L. (2016). Barrier effects of roads on an endangered forest obligate: influences of traffic, road edges, and gaps. BIOLOGICAL CONSERVATION, 199, 33-40.
• Chen, H. L., & Koprowski, J. L. (2016). Differential Effects of Roads and Traffic on Space Use and Movements of Native Forest-Dependent and Introduced Edge-Tolerant Species. PLOS ONE, 11(1).
• Fulgham, K. M., & Koprowski, J. L. (2016). KANGAROO RAT FORAGING IN PROXIMITY TO A COLONY OF REINTRODUCED BLACK-TAILED PRAIRIE DOGS. SOUTHWESTERN NATURALIST, 61(3), 194-202.
• Gwinn, R. N., & Koprowski, J. L. (2016). Differential response to fire by an introduced and an endemic species complicates endangered species conservation. HYSTRIX-ITALIAN JOURNAL OF MAMMALOGY, 27(2).
• Jessen, T., Kilanowski, A., Gwinn, R. N., Merrick, M. J., & Koprowski, J. L. (2016). Microsciurus flaviventer. Mammalian Species, 48(935), 59-65.
• Kellam, J. O., Jansen, D. K., Johnson, A. T., Arwood, R. W., Merrick, M. J., & Koprowski, J. L. (2016). Big Cypress fox squirrel (Sciurus niger avicennia) ecology and habitat use in a cypress dome swamp-pine forest mosaic. JOURNAL OF MAMMALOGY, 97(1), 200-210.
• Kilanowski, A. L., & Koprowski, J. L. (2016). COMMUNAL DENNING OF CLIFF CHIPMUNKS (TAMIAS DORSALIS). SOUTHWESTERN NATURALIST, 61(3), 248-251.
• Koprowski, J. L., Gavish, L., & Doumas, S. (2016). Sciurus anomalus. Mammalian Species, 48(934), 48-58.
• Krishna, M. C., Kumar, A., Tripathi, O. P., & Koprowski, J. L. (2016). Diversity, Distribution and Status of Gliding Squirrels in Protected and Non-protected Areas of the Eastern Himalayas in India. HYSTRIX-ITALIAN JOURNAL OF MAMMALOGY, 27(2).
• Merrick, M. J., & Koprowski, J. L. (2016). Evidence of natal habitat preference induction within one habitat type. PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES, 283(1842).
• Chen, H. L., & Koprowski, J. L. (2015). Animal occurrence and space use change in the landscape of anthropogenic noise. BIOLOGICAL CONSERVATION, 192, 315-322.
• Derbridge, J. J., Merkle, J. A., Bucci, M. E., Callahan, P., Koprowski, J. L., Polfus, J. L., & Krausman, P. R. (2015). Experimentally Derived delta C-13 and delta N-15 Discrimination Factors for Gray Wolves and the Impact of Prior Information in Bayesian Mixing Models. PLOS ONE, 10(3).
• Doumas, S. L., Koprowski, J. L., & Noble, W. O. (2015). LANDSCAPE-LEVEL ASSESSMENT OF ABERT'S SQUIRREL AND RED SQUIRREL IN MIXED CONIFER FOREST. SOUTHWESTERN NATURALIST, 60(2-3), 240-246.
• Koprowski, J. L. (2015). Cudworth, N.L., J.L. Koprowski. Survival and mortality of the Arizona gray squirrel (Sciurus arizonensis).. Southwestern Naturalist, 58, 423-426.
• Koprowski, J. L. (2015). Derbridge, J.J., E.E. Posthumus, H.L. Chen, J.L. Koprowski. 2015. Solenodon paradoxus (Soricomorpha: Solenodontidae).. Mammalian Species, 47(927), 100-106.
• Merrick, M. J., & Koprowski, J. L. (2017). Altered natal dispersal at the range periphery: The role of behavior, resources, and maternal condition.. Ecology and Evolution, 7, 58-72.
• Minor, R. L., & Koprowski, J. L. (2015). Seed Removal Increased by Scramble Competition with an Invasive Species. PLOS ONE, 10(12).
• Palmer, R. R., & Koprowski, J. L. (2015). How do Neotropical pygmy squirrels (Sciurillus pusillus) use seasonally flooded forests in the Peruvian Amazon?. JOURNAL OF MAMMALOGY, 96(6), 1295-1304.
• Paudel, S., Pal, P., Cove, M. V., Jnawali, S. R., Abel, G., Koprowski, J. L., & Ranabhat, R. (2015). The Endangered Ganges River dolphin Platanista gangetica gangetica in Nepal: abundance, habitat and conservation threats. ENDANGERED SPECIES RESEARCH, 29(1), 59-68.
• Posthumus, E. E., Koprowski, J. L., & Steidl, R. J. (2015). Red Squirrel Middens Influence Abundance but Not Diversity of Other Vertebrates. PLOS ONE, 10(4).
• Posthumus, E. E., Koprowski, J. L., & Steidl, R. J. (2015). Red squirrel middens influence abundance but not diversity of other vertebrates. PLoS One, 10(4). doi:10.1371/journal.pone.0123633
• Ramos-Lara, N., & Koprowski, J. L. (2015). Spacing Behavior of a Non-Larder-Hoarding Tamiasciurus: A Study of Mearns's Squirrels in Xeric Coniferous Forests. ETHOLOGY, 121(2), 196-205.
• Steidl, R. J., Koprowski, J. L., & Posthumus, E. E. (2015). Red squirrel middens influence abundance but not diversity of other vertebrates. PLoS One.
• Cudworth, N. L., & Koprowski, J. L. (2014). SURVIVAL AND MORTALITY OF THE ARIZONA GRAY SQUIRREL (SCIURUS ARIZONENSIS). SOUTHWESTERN NATURALIST, 59(3), 423-426.
• Koprowski, J. L., Lara, N. R., Kryštufek, B., & Hoffmann, I. E. (2014). Spermophilus citellus. Mammalian Species, 46, 71-87.
• Koprowski, J. L., Merrick, M. J., & Ketcham, S. L. (2014). Sciurus ignitus. Mammalian Species, 46(915), 93-100.
• Koprowski, J. L., Palmer, R. R., & Scobie, E. H. (2014). Sciurus pyrrhinus. Mammalian Species, 46(914), 88-92.
• Munroe, K. E., & Koprowski, J. L. (2014). Levels of social behaviors and genetic structure in a population of round-tailed ground squirrels (Xerospermophilus tereticaudus).. Behavioral Ecology and Sociobiology, 68, 629-638.
• Munroe, K. E., & Koprowski, J. L. (2014). Levels of social behaviors and genetic structure in a population of round-tailed ground squirrels (Xerospermophilus tereticaudus). BEHAVIORAL ECOLOGY AND SOCIOBIOLOGY, 68(4), 629-638.
• Palmer, G. H., Koprowski, J. L., & Pernas, A. J. (2014). Distribution and spread of an introduced insular population of red-bellied squirrels (Sciurus aureogaster) in Florida. MAMMALIA, 78(1), 67-73.
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  Introduced populations of species pose one of the greatest threats to the persistence of native species. Documentation of distribution, range expansion and habitat use of introduced populations are key components of developing effective management strategies for the control and eradication of invasive species. In 2006 and 2007, we surveyed four islands in Biscayne National Park for nests to evaluate the presence of red-bellied squirrels (Sciurus aureogaster) and the distribution and index of dispersion of their nests in the Florida Keys archipelago within the Atlantic Ocean. Red-bellied squirrels were initially introduced to Elliott Key, Florida, USA in in 1938. We documented evidence of squirrels on two additional islands, Sands Key and Old Rhodes Key, which adds to concerns of spread of this introduced squirrel to areas with endangered endemic insular mammals. Squirrel nests were documented only in mixed-hardwood forest, and nests had a clumped distribution within this forest type. Range expansion was a chief concern to the National Park Service, as continued spread could result in squirrels exiting the park, and prompted management action. Understanding nest site selection and distribution was critical for developing an eradication strategy for the introduced population of red-bellied squirrels from south Florida.
• Palmer, R. R., & Koprowski, J. L. (2014). Feeding behavior and activity patterns of Amazon red squirrels. MAMMALIA, 78(3), 303-313.
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  Foraging sites are important for the survival of animals. Individuals cue on characteristics of the forest that offer enough food resources and also provide safety. During June and July of 2009 and 2010, we studied northern and southern Amazon red squirrels (Sciurus igniventris, S. spadiceus) to determine what forest characteristics were associated with feeding sites. We examined habitat use at three levels: vegetation community where feeding sign was located, site characteristics of the forest immediately surrounding the feeding sign, and the tree exhibiting feeding sign. We measured the site characteristics inside a 10-m radius circular plot, the physical characteristics of the tree exhibiting feeding sign, and the same variables at random locations for comparison. Because there is lack of knowledge about these squirrels, we also conducted focal observations to study their behavior. Squirrels use mainly high and low restinga and selected Astrocaryum and Attalea palm trees that were taller and larger compared with random locations. Squirrels used all vertical strata of the forest, and the main behaviors observed were travel and forage. Behaviors occurred similarly across the day but differed by vertical strata. Although squirrels used vegetation communities different than available and selected for tree characteristics, site characteristics did not appear to be important in contrast with other tree squirrel species.
• Ramos-Lara, N., & Koprowski, J. L. (2014). Deforestation and knowledge gaps threaten conservation of less charismatic species: status of the arboreal squirrels of Mexico. MAMMALIA, 78(4), 417-427.
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  The status of the arboreal squirrels of Mexico was analyzed as a model taxon to elucidate the urgent need that exists worldwide to allocate more funding and research effort to less charismatic species. To accomplish this, we surveyed the literature to review their diversity and present distribution, state of scientific knowledge, and conservation status. We also examined diversity patterns and threats to their persistence. There are currently 14 recognized species, of which four are endemic to the country, with the states of Chiapas and San Luis Potosi possessing the greatest diversity. Presently, seven species are federally listed under some category of risk in Mexico. Our survey yielded only 37 peer-reviewed publications, revealing that a critical dearth of information still exists on the arboreal squirrels of Mexico. We found that states with a greater diversity of arboreal squirrels also have a higher annual wood production, possibly posing a serious threat to their persistence. A common threat to all species is habitat loss caused by deforestation with annual rates >1.0% in the country. Like other less charismatic species in the world, information from local populations is needed to establish suitable regional plans to conserve species facing specific anthropogenic threats.
• Chen, H., & Koprowski, J. (2013). Effects of roads on wildlife in Arizona: how far have we traveled. Biodiversity and Management of the Madrean Archipelago III.
• Cudworth, N. L., & Koprowski, J. L. (2013). Foraging and reproductive behavior of Arizona gray squirrels (Sciurus arizonensis): Impacts of climatic variation. Journal of Mammalogy, 94(3), 683-690.
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  Abstract: Optimal timing of reproduction is critical to ensure adequate conditions for raising young. However, factors influencing timing of reproduction may differ between sexes. Harsh seasonal environments offer unique opportunities to link timing with resource availability and strategies of the sexes. The Arizona gray squirrel (Sciurus arizonensis) inhabits arid forests in which precipitation is highly seasonal and exceptionally variable; however, no data are available on diet or reproduction. We investigated annual variation in foraging and reproductive habits of Arizona gray squirrels to assess responses to extreme seasonality. We found that Arizona gray squirrels have a diverse diet, with consumption of major food items shifting between years. Reproduction also varies between years. Reproductive output was greater in 2008, with more females successfully reproducing and males remaining in reproductive condition for extended periods. Males shifted timing of reproductive behaviors in response to female receptivity, which tracked food availability. This shift likely reflects variation in food production due to precipitation, because rainfall varied greatly, with most years prior to and during our study recording below-average rainfall. With drought conditions and extreme rainfall events predicted to increase with climate change, understanding the relationship between climatic events, phenology of food production, and impacts on reproduction is critical when attempting to manage and conserve species. © 2013 American Society of Mammalogists.
• Cudworth, N. L., & Koprowski, J. L. (2013). Foraging and reproductive behavior of Arizona gray squirrels (Sciurus arizonensis): impacts of climatic variation.. Journal of Mammalogy, 94(3), 683-690.
• Cudworth, N., & Koprowski, J. (2013). Foraging and reproductive behavior of Arizona gray squirrels (Sciurus arizonensis): impacts of climatic variation. Journal of Mammalogy, 94.
• Cudworth, N., & Koprowski, J. (2013). Nest-site characteristics of the montane endemic Mearns s squirrel (Tamiasciurus mearnsi): an obligate cavity-nester?. Journal of Mammalogy 2, 94.
• Doumas, S. L., & Koprowski, J. L. (2013). Effect of heterogeneity in burn severity on Mexican fox squirrels following the return of fire. INTERNATIONAL JOURNAL OF WILDLAND FIRE, 22(3), 405-413.
• Doumas, S. L., & Koprowski, J. L. (2013). Effect of heterogeneity in burn severity on Mexican fox squirrels following the return of fire. International Journal of Wildland Fire, 22(3), 405-413.
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  Abstract: After decades of suppression, fire has returned to many forested areas of the western United States. Understanding responses of wildlife species to fire is essential to native species conservation because contemporary fires may not have the same effects as historical fires. Recent fires in the Chiricahua Mountains of Arizona provided an opportunity to investigate effects of fire heterogeneity on habitat selection of a native wildlife species. We used radiotelemetry to determine home ranges of Mexican fox squirrels (Sciurus nayaritensis chiricahuae) within fire-influenced forests. We then applied resource-utilisation functions to evaluate associations of use intensity within home ranges to heterogeneity of burn severity at two spatial scales. Squirrels used areas with moderate levels of burn heterogeneity at large scale more than areas of low or high heterogeneity. Squirrels used small (
• Doumas, S. L., & Koprowski, J. L. (2013). Effect of heterogeneity in burn severity on Mexican fox squirrels following the return of fire. International Journal of Wildlife Fire, 22(3), 405-413.
• Doumas, S. L., & Koprowski, J. L. (2013). Return of Fire as a Restoration Tool: Long-Term Effects of Burn Severity on Habitat Use by Mexican Fox Squirrels. RESTORATION ECOLOGY, 21(1), 133-139.
• Doumas, S. L., & Koprowski, J. L. (2013). Return of Fire as a Restoration Tool: Long-Term Effects of Burn Severity on Habitat Use by Mexican Fox Squirrels. Restoration Ecology, 21(1), 133-139.
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  Abstract: After decades of suppression, fire is returning to forests of the western United States through wildfires and prescribed burns. These fires may aid restoration of vegetation structure and processes, which could improve conditions for wildlife species and reduce severe wildfire risk. Understanding response of wildlife species to fires is essential to forest restoration because contemporary fires may not have the same effects as historical fires. Recent fires in the Chiricahua Mountains of southeastern Arizona provided opportunity to investigate long-term effects of burn severity on habitat selection of a native wildlife species. We surveyed burned forest for squirrel feeding sign and related vegetation characteristics to frequency of feeding sign occurrence. We used radio-telemetry within fire-influenced forest to determine home ranges of Mexican fox squirrels, Sciurus nayaritensis chiricahuae, and compared vegetation characteristics within home ranges to random areas available to squirrels throughout burned conifer forest. Squirrels fed in forest with open understory and closed canopy cover. Vegetation within home ranges was characterized by lower understory density, consistent with the effects of low-severity fire, and larger trees than random locations. Our results suggest that return of low-severity fire can help restore habitat for Mexican fox squirrels and other native wildlife species with similar habitat affiliations in forests with a historical regime of frequent, low-severity fire. Our study contributes to an understanding of the role and impact of fire in forest ecosystems and the implications for forest restoration as fire returns to the region. © 2012 Society for Ecological Restoration International.
• Doumas, S. L., & Koprowski, J. L. (2013). Return of Fire as a Restoration Tool: Long‐Term Effects of Burn Severity on Habitat Use by Mexican Fox Squirrels.. Restoration Ecology, 21(1), 133-139.
• Fitak, R. R., Koprowski, J. L., & Culver, M. (2013). Severe reduction in genetic variation in a montane isolate: The endangered Mount Graham red squirrel (Tamiasciurus hudsonicus grahamensis). Conservation Genetics, 14(6), 1233-1241.
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  Abstract: The Mount Graham red squirrel (Tamiasciurus hudsonicus grahamensis; MGRS) is endemic to the Pinaleño Mountains of Arizona at the southernmost extent of the species' range. The MGRS was listed as federally endangered in 1987, and is currently at high risk of extinction due to declining population size and increasing threats. Here we present a genetic assessment of the MGRS using eight nuclear DNA microsatellite markers and a 472 bp fragment of the mitochondrial cytochrome b gene. We analyzed 34 MGRS individuals and an additional 66 red squirrels from the nearby White Mountains, Arizona (T. h. mogollonensis). Both nuclear and mitochondrial DNA analyses revealed an extreme reduction in measures of genetic diversity relative to conspecifics from the White Mountains, suggesting that the MGRS has either experienced multiple bottlenecks, or a single long-term bottleneck. Additionally, we found a high degree of relatedness (mean = 0.75 ± 0.18) between individual MGRS. Our study implies that the MGRS may lack the genetic variation required to respond to a changing environment. This is especially important considering this region of the southwest United States is expected to experience profound effects from global climate change. The reduced genetic variability together with the high relatedness coefficients should be taken into account when constructing a captive population to minimize loss of the remaining genetic variation. © 2013 Springer Science+Business Media Dordrecht.
• Fitak, R. R., Koprowski, J. L., & Culver, M. (2013). Severe reduction in genetic variation in a montane isolate: the endangered Mount Graham red squirrel (Tamiasciurus hudsonicus grahamensis).. Conservaton Genetics, 14(6), 1233-1241.
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  Fitak, R. R., Koprowski, J. L., & Culver, M. (2013). Conservation Genetics, 14(6), .
• Gwinn, R., Posthumus, E., & Koprowski, J. (2013). Mustela nudipes (Carnivora: Mustelidae). Mammalian Species.
• Hale, S., Koprowski, J., & Hicks, H. (2013). A review of black-tailed prairie dog reintroduction strategies and site selection: Arizona reintroduction. Biodiversity and Management of the Madrean Archipelago III.
• Jessen, R. R., Palmer, G. H., & Koprowski, J. L. (2013). Maternity nest of an amazon red squirrel in a bromeliad. Mastozoologia Neotropical, 20(1), 159-161.
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  Abstract: Animal-plant interactions are important in the life history of many animal and plant species but our knowledge is often limited. We documented a maternity nest of the poorly studied Amazon red squirrel. The nest was located in a bromeliad and contained two young, a male and a female. We measured nest and forest characteristics and also documented a predation attempt on the adult female while we observed the nest and squirrels. © SAREM, 2013.
• Jessen, R. R., Palmer, G. H., & Koprowski, J. L. (2013). NEOTROPICAL PYGMY SQUIRRELS (SCIURILLUS PUSILLUS) SHARE TERMITE NESTS. ECOTROPICA, 19(1-2), 73-76.
• Jessen, R., Merrick, M., Gwinn, R., & Koprowski, J. (2013). Sciurillus pusillus (Rodentia: Sciuridae). Mammalian Species.
• Ketcham, S., & Koprowski, J. (2013). Impacts of wildfire on wildlife in Arizona: a synthesis. Biodiversity and Management of the Madrean Archipelago III.
• Koprowski, J. L., Jessen, R. R., & Palmer, G. H. (2013). Maternity nest of an amazon red squirrel in a bromeliad.. Mastozoología neotropical, 20(1), 159-161.
• Koprowski, J. L., Palmer, G. H., & Pernas, A. J. (2013). Nest tree and site selection of an introduced population of red-bellied squirrels (Sciurus aureogaster).. Journal of Mammalogy, 94(6), 1274-1281.
• Koprowski, J. L., Pernas, A. J., & Palmer, G. H. (2013). Distribution and spread of an introduced insular population of red-bellied squirrels (Sciurus aureogaster) in Florida. Mammalia, 78(1), 67-73.
• Koprowski, J., Doumas, S., Merrick, M., Oleson, B., Posthumus, E., Jessen, T., & Gwin, R. (2013). It s lonely at the top: biodiversity at risk to loss from climate change. Biodiversity and Management of the Madrean Archipelago III.
• Merrick, M., Koprowski, J., & Wilco, C. (2013). Into the third dimension: benefits of incorporating LiDAR data in wildlife habitat models. Biodiversity and Management of the Madrean Archipelago III.
• Palmer, G. H., Koprowski, J. L., & Pernas, A. J. (2013). Nest tree and site selection of an introduced population of red-bellied squirrels (Sciurus aureogaster). JOURNAL OF MAMMALOGY, 94(6), 1274-1281.
• Palmer, G. H., Koprowski, J. L., & Pernas, A. J. (2013). Nest tree and site selection of an introduced population of red-bellied squirrels (Sciurus aureogaster). Journal of Mammalogy, 94(6), 1274-1281.
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  Abstract: Nests play a crucial role in the life history of tree squirrels, and can be a critical component of their biology that enables them to be a successful invasive species. Red-bellied squirrels (Sciurus aureogaster) were introduced to Elliott Key, Florida, in the late 1930s, and spread to nearby islands. Red-bellied squirrels were believed extirpated by Hurricane Andrew in 1992, but were rediscovered on Elliott Key in 2005. In 2006 and 2007, we surveyed for squirrel nests and measured vegetation to evaluate forest characteristics associated with nest-site selection by squirrels, and compared these data to measurements collected at random locations. Squirrels placed nests in large trees with more canopy linkages in mixed-hardwood forest, and the nest trees were in areas with large trees, high tree density and canopy cover, and lower recent hurricane damage. Red-bellied squirrels selected characteristics of nest trees and forest structure in similar ways to individuals in their native range, and to other species of tree squirrels in general. Results from our research allowed land managers to assess possible management actions and provided important information for them to develop an effective management strategy. Park officials are currently working toward complete eradication of the introduced population of red-bellied squirrels from the Florida Keys. We suggest that behaviors of individuals in native ranges may elucidate patterns for individuals introduced to novel environments; however, we also caution that care must be taken in further extrapolation. Our findings emphasize the importance of understanding ecology of introduced species for effective management. © 2013 American Society of Mammalogists.
• Ramos-Lara, N., Koprowski, J. L., & Swann, D. E. (2013). Nest-site characteristics of the montane endemic Mearns's squirrel (Tamiasciurus mearnsi): An obligate cavity-nester?. Journal of Mammalogy, 94(1), 50-58.
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  Abstract: Many animals depend on nests for their survival and reproduction, with some species considered obligate tree cavity-nesters. Mearns's squirrel (Tamiasciurus mearnsi) is a species endemic to the Sierra de San Pedro Mártir, Baja California, Mexico, that relies on tree cavities for nesting. Federally listed as threatened in Mexico, and as endangered by the International Union for Conservation of Nature, the ecology of this southernmost Tamiasciurus is poorly known. The aim of this study was to examine the nesting requirements of Mearns's squirrels. We used telemetry to locate the nests and 10-m-radius circular plots to compare habitat characteristics between nest sites and random sites, nest sites of males and females, and nest sites of breeding and nonbreeding females. Nest tree species, nest tree condition, nest tree size (diameter at breast height), canopy cover, and occurrence of white firs (Abies concolor) are important characteristics for nesting. Nest sites of males did not differ from those of females except for nest tree condition. Females apparently do not have specific nesting requirements for rearing young. Unlike other congeners that also build leaf nests and underground burrows for nesting, large trees and snags that facilitate cavity formation are critical for the conservation of this species. © 2013 American Society of Mammalogists.
• Ramos-Lara, N., Koprowski, J. L., & Swann, D. E. (2013). Nest-site characteristics of the montane endemic Mearns's squirrel (Tamiasciurus mearnsi): an obligate cavity-nester?. JOURNAL OF MAMMALOGY, 94(1), 50-58.
• Blount, S. J., & Koprowski, J. L. (2012). RESPONSE OF THE MOUNT GRAHAM RED SQUIRREL (TAMIASCIURUS HUDSONICUS GRAHAMENSIS) TO POSTFIRE CONDITIONS. SOUTHWESTERN NATURALIST, 57(1), 8-15.
• Blount, S. J., & Koprowski, J. L. (2012). Response of the Mount Graham red squirrel (Tamiasciurus hudsonicus grahamensis) to postfire conditions. Southwestern Naturalist, 57(1), 8-15.
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  Abstract: To assess response of Mount Graham red squirrels (Tamiasciurus hudsonicus grahamensis) to postfire conditions, we monitored size of home ranges and core areas and characteristics of vegetation at middens in an area of low-intensity burn. For a larger-scale assessment, we monitored mountain-wide occupancy of middens. Although red squirrels selected unburned locations as sites for middens, mean size of home range in a lightly burned area decreased over time, suggesting high availability of resources in lightly burned areas.
• Blount, S., & Koprowski, J. (2012). Small mammal response to post-fire conditions: case of the endangered Mount Graham red squirrel. Southwestern Naturalist, 57, 8-15.
• Doumas, S., & Koprowski, J. (2012). Effect of heterogeneity in burn severity on Mexican fox squirrels following the return of fire. International Journal of Wildland Fir. International J of Wildland Fire.
• Doumas, S., & Koprowski, J. (2012). Return of fire as a restoration tool: long-term effects of burn severity on habitat use by Mexican fox squirrels. Restoration Ecology, 20.
• Gwinn, R. N., Koprowski, J., Jessen, R., & Merrick, M. (2012). Sciurus spadiceus (Rodentia: Sciuridae. Mammalian Species, 44, 59-63.
• Merrick, M., Koprowski, J., & Gwinn, R. (2012). Sciurus stramineus (Rodentia: Sciuridae. Mammalian Species, 44, 44-50.
• Munroe, K. E., & Koprowski, J. L. (2012). COPULATORY PLUGS OF ROUND-TAILED GROUND SQUIRRELS (XEROSPERMOPHILUS TERETICAUDUS). SOUTHWESTERN NATURALIST, 57(2), 208-210.
• Munroe, K. E., & Koprowski, J. L. (2012). Copulatory plugs of round-tailed ground squirrels (Xerospermophilus tereticaudus). Southwestern Naturalist, 57(2), 208-210.
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  Abstract: Sperm competition, where sperm from more than one male competes to fertilize eggs within the reproductive tract of a female, is prevalent in mammals. In rodents, this competition often has led to copulatory plugs, a passive defense against further sperm competition. Copulatory plugs have been reported in many species of sciurids; however, not in round-tailed ground squirrels (Xerospermophilus tereticaudus). Here we report two observations of copulatory plugs in round-tailed ground squirrels and suggest they represent an indirect form of mate guarding in affording males a chance to seek additional mating opportunities as seen in other species of rodents.
• Munroe, K., & Koprowski, J. (2012). Presence of copulatory plugs in round-tailed ground squirrels (Xerospermophilus tereticaudus). Southwestern Naturalist, 57, 210-212.
• Ramos-Lara, N., & Koprowski, J. (2012). Communal nesting behavior in Mearns s squirrels (Tamiasciurus mearnsi). Southwestern Naturalist, 57, 195-198.
• Ramos-Lara, N., & Koprowski, J. L. (2012). COMMUNAL NESTING BEHAVIOR IN MEARNS'S SQUIRRELS (TAMIASCIURUS MEARNSI). SOUTHWESTERN NATURALIST, 57(2), 195-198.
• Ramos-Lara, N., & Koprowski, J. L. (2012). Communal nesting behavior in mearns's squirrels (Tamiasciurus mearnsi). Southwestern Naturalist, 57(2), 195-198.
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  Abstract: Communal nesting has been observed frequently in arboreal squirrels of the genus Sciurus and Glaucomys, but only occasionally in Tamiasciurus. During 2006 and 2007, we trapped and radiocollared 38 adult Mearns's squirrels (Tamiasciurus mearnsi) in Baja California, Mexico, to examine their nesting behavior. We report for the first time instances of communal nesting in Mearns's squirrels. Same-sex groups were more common than mixed-sex groups. Females engaged more in communal nesting than males. Communal nesting behavior in Mearns's squirrels seems to be similar to other species of arboreal squirrels; decreasing as mean monthly temperature increases and during the breeding season.
• Thorington, R., Koprowski, J., Steele, M., & Whatton, J. (2012). Squirrels of the World. Book: Squirrels of the World.
• Cudworth, N. L., & Koprowski, J. L. (2011). Importance of Scale in Nest-Site Selection by Arizona Gray Squirrels. JOURNAL OF WILDLIFE MANAGEMENT, 75(7), 1668-1674.
• Cudworth, N. L., & Koprowski, J. L. (2011). Importance of scale in nest-site selection by Arizona gray squirrels. Journal of Wildlife Management, 75(7), 1668-1674.
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  Abstract: Nests provide a place for individuals to rest, raise young, avoid predators, and escape inclement weather; consequently, knowledge of habitat characteristics important to nest placement is critical for managing species of conservation concern. Arizona gray squirrels (Sciurus arizonensis) are endemic to mountains of southwestern United States and northwestern Mexico. We investigated factors influencing nest-site selection at 4 spatial scales (forest-type, nest-site, nest-tree, and within-canopy placement) to provide ecological information and management recommendations for this sensitive species. Nest densities were 2.6 times higher in riparian than pine-oak woodlands. Nest sites had more large trees, snags, logs, and canopy cover and had lower slope. Arizona gray squirrels selected tall trees with more interlocking trees and tended to place nests adjacent to the main trunk. Regardless of scale, Arizona gray squirrels seemed to select nesting areas for their ability to provide protection from predators and the elements as well as access to food. Consequently, maintaining large trees with closed canopies and downed logs should be considered when determining land management plans. © 2011 The Wildlife Society.
• Cudworth, N., & Koprowski, J. (2011). Microtus californicus. Mammalian Species I, 42, 230-243.
• Cudworth, N., & Koprowski, J. (2011). The importance of scale in nest-site selection in Arizona gray squirrels. Journal of Wildlife Management, 75, 1668-1674.
• Gwinn, R. N., Palmer, G. H., & Koprowski, J. L. (2011). VIRGINIA OPOSSUM (DIDELPHIS VIRGINIANA VIRGINIANA) FROM YAVAPAI COUNTY, ARIZONA. WESTERN NORTH AMERICAN NATURALIST, 71(1), 113-114.
• Gwinn, R. N., Palmer, G. H., & Koprowski, J. L. (2011). Virginia opossum (Didelphis Virginiana Virginiana) from Yavapai County, Arizona. Western North American Naturalist, 71(1), 113-114.
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  Abstract: The Virginia opossum (Didelphis virginiana) is the only marsupial native to the United States. In recent times, D. virginiana has expanded its range through natural movements and anthropogenic introductions. Didelphis virginiana has been present in southern Arizona owing to range expansion by the Mexican subspecies (D. v. californica) and anthropogenic introductions of the eastern subspecies (D. v. virginiana). Here, we document the recent collection of an opossum in central Arizona. We also discuss how it possibly moved there and report on its stomach contents at the time of collection.
• Gwinn, R., Palmer, G., & Koprowski, J. (2011). Sigmodon arizonae. Mammalian Species II, 43, 149-154.
• Gwinn, R., Palmer, G., & Koprowski, J. (2011). Virginia opossum (Didelphis virginiana virginiana)from Yavapai County, Arizona. Western North American Naturalist, 71, 113-114.
• Merrick, M. J., Koprowski, J. L., Gwinn, R. N., Palmer, G. H., & Zugmeyer, C. A. (2011). STATUS OF RED SQUIRRELS IN GUADALUPE MOUNTAINS NATIONAL PARK, TEXAS. SOUTHWESTERN NATURALIST, 56(1), 24-28.
• Merrick, M. J., Koprowski, J. L., Gwinn, R. N., Palmer, G. H., & Zugmeyer, C. A. (2011). Status of red squirrels in Guadalupe mountains national park, Texas. Southwestern Naturalist, 56(1), 24-28.
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  Abstract: The Pinaleño Mountains of southeastern Arizona contain the southernmost population of red squirrels (Tamiasciurus hudsonicus) in North America. Red squirrels historically inhabited the Guadalupe Mountains in Trans-Pecos Texas during the Pleistocene and the possibility that red squirrels currently persist has been suggested by several biologists visiting the upper-elevation forests. Herein, we report results of an assessment of small mammals in coniferous forest where we used observational line transects, playback calls, and live trapping to determine status of red squirrels. We surveyed 132 ha of coniferous forest along 8.9 km of transects and observed and found evidence of 10 species of mammals. We detected no evidence of red squirrels inhabiting high-elevation coniferous forest.
• Merrick, M., Koprowski, J., Gwinn, R., Palmer, G., & Zugmeyer, C. (2011). Surveys to determine the status of red squirrels in Guadalupe Mountains National Park, Texas. Southwestern Naturalist, 56, 24-28.
• Munroe, K. E., & Koprowski, J. L. (2011). Sociality, Bateman's gradients, and the polygynandrous genetic mating system of round-tailed ground squirrels (Xerospermophilus tereticaudus). BEHAVIORAL ECOLOGY AND SOCIOBIOLOGY, 65(9), 1811-1824.
• Munroe, K. E., & Koprowski, J. L. (2011). Sociality, Bateman's gradients, and the polygynandrous genetic mating system of round-tailed ground squirrels (Xerospermophilus tereticaudus). Behavioral Ecology and Sociobiology, 65(9), 1811-1824.
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  Abstract: Historically, most mammals have been classified as polygynous; although recent molecular evidence suggests that many mammals may be polygynandrous, particularly the ground-dwelling sciurids. We genotyped 351 round-tailed ground squirrels (Xerospermophilus tereticaudus) using seven microsatellite loci to determine paternity in 31 litters from 2004 to 2007. Polygyny was evident in all years except in 2007, when the population size was reduced. Multiple paternity occurred in the majority of litters (55%) with 2. 5 ± 0. 26 sires/litter (n = 31). Forty-nine percent of resident males (n = 114) sired offspring, and of males that sired offspring (n = 56) 27% sired young in multiple litters in a single breeding season. Litter size was positively correlated with the number of sires. Through an indirect analysis of paternity, we found 21 litters (68%) with an average relatedness of 0. 5 or less. Males had a greater opportunity for sexual selection (Is = 1. 60) than females (Is = 0. 40); Bateman's gradient was also greater in males (1. 07 ± 0. 04, n = 56) than females (0. 82 ± 0. 08, n = 31). The mating system in round-tailed ground squirrels defined through genetic analyses and Bateman's gradients is polygynandrous compared to the previously suggested polygynous mating system as established by behavioral observations and fits within the predictions of the ground squirrel sociality models. Upon evaluating the predictions of the sociality models among sciurid species, we found a negative relationship between the level of sociality with litter size and the average percentage of multiple paternity within a litter. Thus, recent genetic information and reclassification of mating systems support the predictions of the ground-dwelling squirrel sociality models. © 2011 Springer-Verlag.
• Munroe, K., & Koprowski, J. (2011). Sociality, Bateman's gradients and the polygynandrous genetic mating system of round-tailed ground squirrels (Xerospermophilus tereticaudu. Behavioral Ecology, 65, 1811-182.
• Pasch, B., & Koprowski, J. (2011). Impacts of fire suppression on space use of Mexican fox squirrels. Journal of Mammalogy, 92, 227-234.
• Pasch, B., & Koprowski, J. L. (2011). Impacts of fire suppression on space use by Mexican fox squirrels. JOURNAL OF MAMMALOGY, 92(1), 227-234.
• Pasch, B., & Koprowski, J. L. (2011). Impacts of fire suppression on space use by Mexican fox squirrels. Journal of Mammalogy, 92(1), 227-234.
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  Abstract: Human suppression of fire has resulted in altered species composition and dense forest stands across the western United States. Accumulation of understory shrubs makes forests vulnerable to catastrophic fire and can impact animal use, whereas fire prescription can ameliorate negative impacts of suppression. We used radiotelemetry to determine patterns of habitat use and survival of Mexican fox squirrels (Sciurus nayaritensis chiricahuae) in fire-suppressed and fire-prescribed areas of the Chiricahua Mountains, Arizona. Core areas of squirrels within fire-suppressed areas were larger and contained more understory shrubs than core areas of squirrels in fire-prescribed areas. Shrub cover and canopy heterogeneity influenced core-area size and distance traveled, and squirrels that were depredated traveled farther than conspecifics that survived, but shrub cover and canopy heterogeneity were not directly associated with squirrel survival. Suppression-induced increases in understory vegetation might force squirrels to travel greater distances to meet energetic requirements and thereby increase predation risk. Retention of mature forested canyons and restoration of natural fire regimes will be important for the persistence of Mexican fox squirrels. © 2011 American Society of Mammalogists.
• Cudworth, N. L., & Koprowski, J. L. (2010). FIRST RECORD OF A RANGE EXTENSION OF THE CLIFF CHIPMUNK (TAMIAS DORSALIS) INTO THE HUACHUCA MOUNTAINS. WESTERN NORTH AMERICAN NATURALIST, 70(3), 418-420.
• Cudworth, N. L., & Koprowski, J. L. (2010). First record of a range extension of the cliff chipmunk (Tamias dorsalis) into the Huachuca Mountains. Western North American Naturalist, 70(3), 418-420.
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  Abstract: Chipmunks are widely distributed throughout the mountain ranges of Arizona. However, no living chipmunks are known from the Huachuca Mountains despite the availability of favorable habitat. Based upon pelage characteristics of captured individuals, we provide the first report of a breeding population of cliff chipmunks (Tamias dorsalis) in the Huachuca Mountains and discuss possible mechanisms of their arrival. © 2010 Western North American Naturalist.
• Cudworth, N. L., & Koprowski, J. L. (2010). Influences of mating strategy on space use of Arizona gray squirrels. JOURNAL OF MAMMALOGY, 91(5), 1235-1241.
• Cudworth, N. L., & Koprowski, J. L. (2010). Influences of mating strategy on space use of Arizona gray squirrels. Journal of Mammalogy, 91(5), 1235-1241.
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  Abstract: Space use frequently differs between sexes and may reflect differences in parental investment and limiting resources. We examined Arizona gray squirrels (Sciurus arizonensis) from April 2007 to December 2008 to determine effects of mating strategy on patterns of home-range size and overlap. Home ranges were large compared to those of congeners, suggesting an environment with low availability and predictability of resources, and differed by sex and season. Females maintained smaller home ranges overlapped more by males than females; overlap by male home ranges increased during the breeding season. Males had larger home ranges that overlapped females more than males; home-range size and overlap of both sexes increased during the breeding season. Additionally, male Arizona gray squirrels appear to respond to the distribution of females by enlarging home ranges to maximize proportion of females overlapped. Consequently, Arizona gray squirrels conform to theoretical predictions, with female space use influenced by access to food and male space use influenced by access to mates. © 2010 American Society of Mammalogists.
• Jessen, R. R., Merrick, M. J., Koprowski, J. L., & Ramirez, O. (2010). Presence of Guayaquil squirrels on the central coast of Peru: An apparent introduction. Mammalia, 74(4), 443-444.
• Jessen, R. R., Merrick, M. J., Koprowski, J. L., & Ramirez, O. (2010). Presence of Guayaquil squirrels on the central coast of Peru: an apparent introduction. MAMMALIA, 74(4), 443-444.
• Leonard, K. M., & Koprowski, J. L. (2010). EFFECTS OF FIRE ON ENDANGERED MOUNT GRAHAM RED SQUIRRELS (TAMIASCIURUS HUDSONICUS GRAHAMENSIS): RESPONSES OF INDIVIDUALS WITH KNOWN FATES. SOUTHWESTERN NATURALIST, 55(2), 217-224.
• Leonard, K. M., & Koprowski, J. L. (2010). Effects of fire on endangered mount graham red squirrels (tamiasciurus hudsonicus grahamensis): Responses of individuals with known fates. Southwestern Naturalist, 55(2), 217-224.
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  Abstract: We studied demography and behavior of endangered Mount Graham red squirrels (Tamiasciurus hudsonicus grahamensis) inhabiting areas within and outside low-intensity burns following the Nuttall Fire in the Pinaleño Mountains, Arizona. Body mass, proportion of individuals in reproductive condition, and distance squirrels traveled to nest did not differ between squirrels within and outside the perimeter of the fire. Within the perimeter, red squirrels had smaller home ranges and shifted territories less frequently and had shorter distances from their previously held territories than squirrels outside the perimeter. Mount Graham red squirrels evolved with patchy, low-intensity fires like those that burned in mixed-conifer forests in the Pinaleño Mountains and may be able to persist in areas affected by this level of disturbance.
• Merrick, M. J., Gwinn, R. N., Minor, R. L., Jessen, R. R., Jessen, T. G., Greer, V. L., & Koprowski, J. L. (2010). ENDANGERED MOUNT GRAHAM RED SQUIRREL (TAMIASCIURUS HUDSONICUS GRAHAMENSIS) USES NEST FOLLOWING LIGHTNING STRIKE. SOUTHWESTERN NATURALIST, 55(1), 123-124.
• Merrick, M. J., Gwinn, R. N., Minor, R. L., Jessen, R. R., Jessen, T. G., Greer, V. L., & Koprowski, J. L. (2010). Endangered mount Graham Red squirrel (Tamiasciurus hudsonicus grahamensis) uses nest following lightning strike. Southwestern Naturalist, 55(1), 123-124.
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  Abstract: Few studies have documented behavioral response of small mammals to fire. Here we report use of a nest by an adult Mount Graham red squirrel (Tamiasciurus hudsonicus grahamensis), an endangered subspecies endemic to the Pinaleño Mountains of southeastern Arizona, following a direct lightning strike to a tree. After 2 days, the squirrel nested in this tree and remained in the area for another 136 days. This is evidence that red squirrels may tolerate some degree of fire on the landscape.
• Edelman, A. J., Koprowski, J. L., & Bertelsen, S. R. (2009). POTENTIAL FOR NEST SITE COMPETITION BETWEEN NATIVE AND EXOTIC TREE SQUIRRELS. JOURNAL OF MAMMALOGY, 90(1), 167-174.
• Edelman, A. J., Koprowski, J. L., & Bertelsen, S. R. (2009). Potential for nest site competition between native and exotic tree squirrels. Journal of Mammalogy, 90(1), 167-174.
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  Abstract: In communities where strong interspecific competition between native species is lacking, exotic and native species often exhibit intense resource competition resulting in decline of native populations. We examined the potential for interspecific competition for nest sites between co-occurring native Mt. Graham red squirrels (Tamiasciwus hudsonicus grahamensis) and exotic Abert's squirrels (Sciurus aberti) in the Pinaleno Mountains of Arizona. Comparison of nest use between red and Abert's squirrels at different scales (nest, nest tree, and nest site) revealed contrasting results. Competition for nests and nest trees appears unlikely given the dissimilarity in use of nest types and tree characteristics. Abert's squirrels predominately used dreys, whereas red squirrels mostly used cavity nests. Neither squirrel species occupied a nest used by the other species. Nest trees differed in size and species between squirrels for dreys, but not for cavities. Abert's squirrel nest sites were found in a wider range of microhabitats including almost all microhabitats in which red squirrel nest sites were located. Although there was significant overlap, each species showed distinct trends in microhabitat. In general, red squirrel nest sites were characterized as more densely forested areas dominated by corkbark fir (Abies lasiocarpa var. arizonica), whereas Abert's squirrel nest sites were more open and contained greater tree species diversity. Overlap in microhabitat characteristics increases the likelihood of interspecific competition and could increase the vulnerability of red squirrels to extinction. © 2009 American Society of Mammalogists.
• Leonard, K. M., & Koprowski, J. L. (2009). A Comparison of Habitat Use and Demography of Red Squirrels at the Southern Edge of Their Range. AMERICAN MIDLAND NATURALIST, 162(1), 125-138.
• Leonard, K. M., & Koprowski, J. L. (2009). A comparison of habitat use and demography of red squirrels at the southern edge of their range. American Midland Naturalist, 162(1), 125-138.
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  Abstract: Populations at the edge of their geographic range may demonstrate different population dynamics from central populations. Endangered Mt. Graham red squirrels (Tamiasciurus hudsonicus grahamensis), endemic to southeastern Arizona, represent the southernmost red squirrel population and are found at lower densities than conspecifics in the center of the range. To determine if differences are due to conditions at the southern periphery of the range, we compared habitat characteristics, demography, body mass, space use and nesting behavior with another subspecies located at the southern edge of the range, the Mogollon red squirrel (T. h. mogollonensis). We found that mean and minimum daily temperatures were higher at Mt. Graham whereas maximum temperatures were higher in the White Mountains, male Mogollon red squirrels were heavier than male Mt. Graham red squirrels in all seasons and female Mogollon red squirrels were slightly heavier than female Mt. Graham red squirrels in spring, proportion of squirrels in reproductive condition was lower in female Mogollon red squirrels, Mogollon red squirrels had smaller home ranges, used different types of nests and traveled less distance to nest than Mt. Graham red squirrels. There were no differences in annual rainfall, seedfall, habitat characteristics or survival between mountain ranges. Localized conditions appear to account for the disparity between populations. These differences demonstrate the importance of evaluating attributes of peripheral populations for maximizing persistence and intraspecific diversity.
• Zugmeyer, C. A., & Koprowski, J. L. (2009). HABITAT SELECTION IS UNALTERED AFTER SEVERE INSECT INFESTATION: CONCERNS FOR FOREST-DEPENDENT SPECIES. JOURNAL OF MAMMALOGY, 90(1), 175-182.
• Zugmeyer, C. A., & Koprowski, J. L. (2009). Habitat selection is unaltered after severe insect infestation: Cncerns for forest-dependent species. Journal of Mammalogy, 90(1), 175-182.
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  Abstract: Severe disturbance may alter or eliminate important habitat structure that helps preserve food caches of food- hoarding species. Recent recolonization of an insect-damaged forest by the endangered Mt. Graham red squirrel (Tamiasciurus hudsonicus grahamensis) provided an opportunity to examine habitat selection for midden (cache) sites following disturbance. From September 2003 to December 2005, we examined surface temperature and physical and vegetative characteristics associated with random locations and midden sites in insect-damaged forests. Red squirrel use of midden sites that are similar in structure to those used before insect infestation indicates that insect infestation did not eliminate midden habitat. However, differences between occupied middens and historical middens that are unoccupied reflect the severity of insect infestation tolerated by red squirrels. Occupied middens had
• Zugmeyer, C. A., & Koprowski, J. L. (2009). Severely insect-damaged forest: A temporary trap for red squirrels?. FOREST ECOLOGY AND MANAGEMENT, 257(2), 464-470.
• Zugmeyer, C. A., & Koprowski, J. L. (2009). Severely insect-damaged forest: A temporary trap for red squirrels?. Forest Ecology and Management, 257(2), 464-470.
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  Abstract: Recent insect infestations in the spruce-fir forest in the Pinaleño Mountains of southeastern Arizona provided an opportunity to document response to severe forest disturbance and existence of an ecological trap for an endemic montane isolate, the endangered Mt. Graham red squirrel (Tamiasciurus hudsonicus grahamensis). From September 2003 to December 2005 we assessed habitat selection and home range dynamics, and monitored potential correlates of fitness (body mass, reproduction, survivorship) in red squirrels living in insect-damaged forest, while drawing comparisons to squirrels inhabiting undamaged mixed-conifer forest. Although Mt. Graham red squirrels demonstrate equal-preference for habitat within insect-damaged forests and reproduce as well as individuals in undamaged forest, poor survivorship and reduced potential to reproduce suggest insect-damaged forest may function as an ecological trap. In addition, areas selected within insect-damaged forest had
• Koprowski, J. L., & Nandini, R. (2008). Global hotspots and knowledge gaps for tree and flying squirrels. CURRENT SCIENCE, 95(7), 851-856.
• Koprowski, J. L., & Nandini, R. (2008). Global hotspots and knowledge gaps for tree and flying squirrels. Current Science, 95(7), 851-856.
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  Abstract: Tree and flying squirrels are important components of forested ecosystems, and are advocated as indicators of forest health. In this global assessment of the distribution, endangerment and scientific knowledge of squirrels, we reveal trends that warrant urgent attention. The tropics, particularly the forests of south and southeast Asia, are hotspots of squirrel diversity; however, this region generates the fewest scientific publications on squirrels. Additionally, the most endangered squirrels occur in tropical countries with high deforestation rates, and flying squirrels are more at risk than tree squirrels. Given the combination of high diversity, extinction risk and lack of knowledge of sciurids in the tropics, we recommend increased effort towards understanding their occurrence and biology in the imperiled tropical forests.
• Koprowski, J. L., King, S. R., & Merrick, M. J. (2008). Expanded home ranges in a peripheral population: Space use by endangered Mt. Graham red squirrels. Endangered Species Research, 4(1-2), 227-232.
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  Abstract: Peripheral populations are often of increased conservation value; however, knowledge of the ecological and evolutionary consequences of a peripheral location is poor. Spatial dynamics are often interpreted as strategies to maximize access to fitness-limiting resources. Red squirrels Tamiasciurus hudsonicus are territorial in western portions of their range and exhibit overlapping home ranges in eastern forests. Endangered Mt. Graham red squirrels T. hudsonicus grahamensis represent southernmost extension of the species. We used radiotelemetry to assess space use and interindividual overlap of endangered Mt. Graham red squirrels. Squirrels maintained nearly exclusive 50 % core areas; however, 95 % ranges overlapped considerably, especially between males and females. Home ranges increased in summer for both males and females and may be related to sex-specific reproductive strategies. Ranges of Mt. Graham red squirrels in this peripheral population were nearly 10 times the size of red squirrels from other locations. The space use of this limital population suggests that resource availability may be substantially different than in other portions of the range. © Inter-Research 2008.
• Lurz, P. W., Koprowski, J. L., & Wood, D. J. (2008). The use of GIS and modelling approaches in squirrel population management and conservation: A review. Current Science, 95(7), 918-922.
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  Abstract: We review modelling approaches in relation to three key areas of sciurid ecology: management, disease risk assessments and conservation. Models enable us to explore different scenarios to develop effective management and conservation strategies. They may also assist in identifying and targeting research needs for tree and flying squirrels. However, there is a need to refine techniques and assure that data used are applicable at the appropriate scale. Models allow managers to make informed decisions to help conserve species, but success requires that the utility of the tool be evaluated as new empirical data become available and models refined to more accurately meet the needs of current conservation scenarios.
• Lurz, P., Koprowski, J. L., & Wood, D. (2008). The use of GIS and modelling approaches in squirrel population management and conservation: a review. CURRENT SCIENCE, 95(7), 918-922.
• Edelman, A. J., & Koprowski, J. L. (2007). Communal nesting in asocial Abert's squirrels: The role of social thermoregulation and breeding strategy. Ethology, 113(2), 147-154.
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  Abstract: The social thermoregulation hypothesis states that endothermic species will communally nest to reduce energy expenditures on thermoregulation. The hypothesis predicts that the frequency of communal nesting should increase with decreasing ambient temperature. The potential costs of communal nesting (e.g., increased predation risk, resource competition, cuckoldry, parasite/disease transmission, or infanticide) could decrease the frequency of communal nesting especially for asocial breeding females with dependent offspring. We examined the effects of ambient temperature and seasonal reproductive activities on the probability of communal nesting in Abert's squirrels (Sciurus aberti) in the Pinaleño Mountains, Arizona. Most squirrels nested consistently with the same partner in mixed-sex pairs. The proportion of individuals engaging in communal nesting increased with decreasing ambient temperature as predicted by the social thermoregulation hypothesis. The onset of the breeding season greatly reduced the proportion of individuals communally nesting. The negative relationship between ambient temperature and communal nesting supports the use of communal nesting in Abert's squirrels as a mechanism to reduce thermoregulatory costs during cold conditions. The abrupt drop in the frequency of communal nesting during the breeding season is likely due to female abandonment of this behavior. By avoiding communally nesting during the breeding season, females may prevent males from mating with them outside of mating chases, reduce resource competition, and protect offspring from infanticide, diseases, and parasites. Males may gain additional fitness benefits from nesting with females because familiarity with females increases dominance rank in mating activities. © 2007 The Authors Journal compilation 2007 Blackwell Verlag, Berlin.
• Edelman, A. J., & Koprowski, J. L. (2007). Communal nesting in asocial abert's squirrels: The role of social thermoregulation and breeding strategy. ETHOLOGY, 113(2), 147-154.
• J., D., Drake, S., Rushton, S. P., Rautenkranz, D., W., P., & Koprowski, J. L. (2007). Fine-scale analysis of Mount Graham red squirrel habitat following disturbance. Journal of Wildlife Management, 71(7), 2357-2364.
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  Abstract: Habitat destruction and degradation are major factors in reducing abundance, placing populations and species in jeopardy. Monitoring changes to habitat and identifying locations of habitat for a species, after disturbance, can assist mitigation of the effects of human-caused or -amplified habitat disturbance. Like many areas in the western United States, the Pinaleno Mountains of southeastern Arizona, USA, have suffered catastrophic fire and large-scale insect outbreaks in the last decade. The federally endangered Mt. Graham red squirrel (Tamiasciurus hudsonicus grahamensis) is only found in the Pinaleño Mountains, and to assess effects of forest disturbance on habitat we modeled their potential habitat by identifying characteristics of cover surrounding their centrally defended middens. We classified high-spatial resolution satellite imagery into ground cover classes, and we used logistic regression to determine areas used by squirrels. We also used known midden locations in conjunction with slope, elevation, and aspect to create a predictive habitat map. Squirrels selected areas of denser forest with higher seedfall for midden sites. Among active middens, those in the densest and least damaged forests were occupied in more seasons than those in more fragmented and damaged areas. The future conservation of red squirrels and the return of healthy mature forests to the Pinaleño Mountains will rely on preservation of mixed conifer zones of the mountain and active restoration of spruce-fir forests to return them to squirrel habitat. Our ability to evaluate the spectrum of fine- to coarse-scale disturbance effects (individual tree mortality to area wide boundaries of a disturbance) with high-resolution satellite imagery shows the utility of this technique for monitoring future disturbances to habitat of imperiled species.
• J., D., Koprowski, J. L., & W., P. (2007). Tree squirrel introduction: A theoretical approach with population viability analysis. Journal of Mammalogy, 88(5), 1271-1279.
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  Abstract: Reintroduction efforts require knowledge of how many animals are needed for successful establishment. Population viability analysis can be used to predict trajectories of introduced populations and tree squirrels provide an ideal model system to investigate this challenge. Conservation action is needed because more than 80% of species of tree squirrels are of precarious conservation status in some portion of their range. We combined data from closely related species of tree squirrels and used VORTEX to determine how many squirrels are needed to successfully establish populations of 6 species (Sciurus aberti, S. carolinensis, S. niger, S. granatensis, S. vulgaris, and Tamiasciurus hudsonicus). We ran multiple simulations to account for between-patch differences in breeding success (resource availability) and variation between years in different habitats. In the best-case scenarios, populations could be successfully established with fewer than 35 individuals for all species and as few as 15 for a subset of species. Empirical evidence from introductions of tree squirrels supports our simulation results, with 93% of populations of greater than 10 squirrels surviving more than 50 years. With relatively few individuals needed for establishing new squirrel populations, reintroductions are feasible and useful as a buffer for imperiled species. © 2007 American Society of Mammalogists.
• Johnson, H. E., Bleich, V. C., Krausman, P. R., & Koprowski, J. L. (2007). Effects of antler breakage on mating behavior in male tule elk (Cervus elaphus nannodes) (vol 53, pg 16, 2007). EUROPEAN JOURNAL OF WILDLIFE RESEARCH, 53(1), 16-18.
• Johnson, H. E., Bleich, V. C., Krausman, P. R., & Koprowski, J. L. (2007). Effects of antler breakage on mating behavior in male tule elk (Cervus elaphus nannodes). EUROPEAN JOURNAL OF WILDLIFE RESEARCH, 53(1), 9-15.
• Johnson, H. E., Bleich, V. C., Krausman, P. R., & Koprowski, J. L. (2007). Effects of antler breakage on mating behavior in male tule elk (Cervus elaphus nannodes). European Journal of Wildlife Research, 53(1), 9-15.
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  Abstract: Although antler size has been identified as a primary determinant of dominance, fighting success, and reproductive success in male cervids, >80% of the male tule elk (Cervus elaphus nannodes) in the Owens Valley, California, experience antler breakage. To determine the effect of antler breakage on male mating success, we recorded antler morphology, body size, and mating behavior of male elk throughout the rut. Antler breakage, regardless of severity, had no effect on male-male assessment, fighting success, or harem-holding status. The factor consistently associated with our indices of male mating success was not antler size but body size. Although antler size is frequently emphasized as a key factor in male dominance and social rank, this association may reflect the correlation between antler size and body size. In the Owens Valley, it appears that male elk are not assessing competitors based on antler morphology but on other characteristics. © 2006 Springer-Verlag.
• Johnson, H. E., Bleich, V. C., Krausman, P. R., & Koprowski, J. L. (2007). Erratum: Effects of antler breakage on mating behavior in male tule elk (Cervus elaphus nannodes) (European Journal of Wildlife Research DOI: 10.1007/s10344-006-0060-4). European Journal of Wildlife Research, 53(1), 16-18.
• Merrick, M. J., Bertelsen, S. R., & Koprowski, J. L. (2007). Characteristics of Mount Graham red squirrel nest sites in a mixed conifer forest. JOURNAL OF WILDLIFE MANAGEMENT, 71(6), 1958-1963.
• Merrick, M. J., Bertelsen, S. R., & Koprowski, J. L. (2007). Characteristics of mount graham red squirrel nest sites in a mixed conifer forest. Journal of Wildlife Management, 71(6), 1958-1963.
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  Abstract: The Mount Graham red squirrel (Tamiasciurus hudsonicus grahamensis) is constrained to the Pinaleño Mountains in southeastern Arizona, USA. The population's endangered status and extensive forest damage from insects and fire warrants a better understanding of habitat variables important for nest site selection. We examined characteristics of cavity (n = 91) and drey (n = 38) nests and compared these to random sites (n = 113). Dreys were found primarily in Engelmann spruce (Picea engelmannii) and corkbark fir (Abies lasiocarpa var. arizonica). Cavity nests occurred primarily in aspen (Populus tremuloides) and corkbark fir. Squirrels selected nest sites with higher canopy cover and more corkbark fir, decayed logs, and living trees. Forest management plans emphasizing thinning must consider how altering these habitat characteristics could affect availability and suitability of tree stands for nesting squirrels.
• Wood, D., Drake, S., Rushton, S. P., Rautenkranz, D., Lurz, P., & Koprowski, J. L. (2007). Fine-scale analysis of mount graham red squirrel habitat following disturbance. JOURNAL OF WILDLIFE MANAGEMENT, 71(7), 2357-2364.
• Wood, D., Koprowski, J. L., & Lurz, P. (2007). Tree squirrel introduction: A theoretical approach with population viability analysis. JOURNAL OF MAMMALOGY, 88(5), 1271-1279.
• Zugmeyer, C. A., & Koprowski, J. L. (2007). Avian nestling predation by endangered Mount Graham red squirrel. SOUTHWESTERN NATURALIST, 52(1), 155-157.
• Zugmeyer, C. A., & Koprowski, J. L. (2007). Avian nestling predation by endangered Mount Graham red squirrel. Southwestern Naturalist, 52(1), 155-157.
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  Abstract: Studies using artificial nests or remote cameras have documented avian predation by red squirrels (Tamiasciurus hudsonicus). Although several direct observations of avian predation events are known in the northern range of the red squirrel distribution, no accounts have been reported in the southern portion. We observed predation upon a hermit thrush (Catharus guttatus) nestling by the Mount Graham red squirrel (T. h. grahamensis), an endangered subspecies living at the southern terminus of the distribution of the red squirrel.
• Edelman, A. J., & Koprowski, J. L. (2006). Characteristics of Abert's squirrel (Sciurus aberti) cavity nests. SOUTHWESTERN NATURALIST, 51(1), 64-70.
• Edelman, A. J., & Koprowski, J. L. (2006). Characteristics of Abert's squirrel (Sciurus aberti) cavity nests. Southwestern Naturalist, 51(1), 64-70.
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  Abstract: Cavity nests are rarely used by Abert's squirrels (Sciurus aberti) in ponderosa pine (Pinus ponderosa) forests. Introduced Abert's squirrels in the Pinaleño Mountains of Arizona, however, exhibit occasional use of cavity nests (ca. 10%). We examined characteristics of cavity nest sites in this introduced population. Cavity nests were located at two-thirds of the tree height and were found mainly in both dead and five aspen (Populus treuruloides). Aspen cavity trees were larger than aspen random trees. Aspen cavity sites had more large snags and less ponderosa pine and were less steep than aspen random sites. Abert's squirrels possibly use cavities in large aspen trees because thick trunks and older trees might allow larger cavities to form, might provide greater thermal and wind protection, or both. The greater use of cavity nests by the Abert's squirrels in our study could be due to the higher frequency of cavity-forming aspens or harsher winter conditions in mixed-conifer forests of the Pinaleño Mountains than in ponderosa pine forests where Abert's squirrels typically occur or both.
• Edelman, A. J., & Koprowski, J. L. (2006). Influence of female-biased sexual size dimorphism on dominance of female Townsend's chipmunks. CANADIAN JOURNAL OF ZOOLOGY-REVUE CANADIENNE DE ZOOLOGIE, 84(12), 1859-1863.
• Edelman, A. J., & Koprowski, J. L. (2006). Influence of female-biased sexual size dimorphism on dominance of female Townsend's chipmunks. Canadian Journal of Zoology, 84(12), 1859-1863.
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  Abstract: Female-biased sexual size dimorphism (SSD), a condition common in North American chipmunks, occurs when females are larger than males in a species. We examined the influence of body size on dominance of captive female Townsend's chipmunks (Tamias townsendii Bachman, 1839), a species that exhibits female-biased SSD, in all-female and mixed-sex dyadic encounters. In all-female dyads, large female chipmunks were more frequently dominant over small female opponents. In mixed-sex dyads, large females were always dominant over small males. Female-biased SSD in Townsend's chipmunks appears to indirectly allow large females to more frequently dominate small female and male conspecifics. Greater dominance could increase reproductive success of large female chipmunks by increasing access to resources. © 2006 NRC.
• Edelman, A. J., & Koprowski, J. L. (2006). Seasonal changes in home ranges of Abert's squirrels: Impact of mating season. Canadian Journal of Zoology, 84(3), 404-411.
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  Abstract: We compared home ranges of introduced Abert's squirrels (Sciurus aberti Woodhouse, 1853) in mixed-conifer forests of Arizona during non-mating and mating seasons. Because Abert's squirrels are reported to depend on ponderosa pine (Pinus ponderosa P. & C. Lawson) forests, the mixed-conifer forest in our study represented a novel habitat. Home-range size, home-range overlap with females, and movement distances increased for males from non-mating to mating seasons. Home-range size and overlap characteristics of females remained consistent between seasons, but movement distances were reduced during the mating season. Males probably increased home-range size, home-range overlap with females, and movement distances during the mating season to maximize contact with scarce females. Home-range size and overlap characteristics of female Abert's squirrels likely remained stable between seasons because females do not search for mates. Restricted movements by females during the mating season may be due to changes in resource use in preparation for reproduction. Non-mating season home ranges in our study were smaller than home ranges observed in ponderosa pine forest. Abert's squirrels in mixed-conifer forest may have small home ranges because resource quality is higher than in ponderosa pine forest or competition for space with co-occurring Mount Graham red squirrels (Tamiasciurus hudsonicus grahamensis (J.A. Allen, 1894)). © 2006 NRC.
• Edelman, A. J., & Koprowski, J. L. (2006). Seasonal changes in home ranges of Abert's squirrels: impact of mating season. CANADIAN JOURNAL OF ZOOLOGY-REVUE CANADIENNE DE ZOOLOGIE, 84(3), 404-411.
• Koprowski, J. L., Leonard, K. M., Zugmeyer, C. A., & Jolley, J. L. (2006). Direct effects of fire on endangered Mount Graham red squirrels. SOUTHWESTERN NATURALIST, 51(1), 59-63.
• Koprowski, J. L., Leonard, K. M., Zugmeyer, C. A., & Jolley, J. L. (2006). Direct effects of fire on endangered Mount Graham red squirrels. Southwestern Naturalist, 51(1), 59-63.
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  Abstract: Direct mortality of forest wildlife due to fire is rarely documented. In June and July 2004, the Nuttall Complex Fire burned 11,898 ha in the Pinaleño Mountains, southeastern Arizona. Portions of these mountains serve as the only habitat of endangered Mount Graham red squirrels (Tamiasciurus hudsonicus grahamensis). Survival of radio-collared red squirrels over a period that included the fire was lower in areas that were burned than on unburned areas; however, the majority of squirrels on our study areas survived the fire. Distance of nests from middens did not differ between pre-fire and post-fire periods for animals in burned or unburned areas, indicating that squirrels did not abandon middens immediately after surviving the effects of fire.
• Koprowski, J. L., Ramos, N., Pasch, B. S., & Zugmeyer, C. A. (2006). Observations on the ecology of the endemic Mearns's squirrel (Tamiasciurus mearnsi). SOUTHWESTERN NATURALIST, 51(3), 426-430.
• Koprowski, J. L., Ramos, N., Pasch, B. S., & Zugmeyer, C. A. (2006). Observations on the ecology of the endemic Mearns's squirrel (Tamiasciurus mearnsi). Southwestern Naturalist, 51(3), 426-430.
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  Abstract: Mearns's squirrel (Tamiasciurus mearnsi) is an endemic species of the montane forest of the Sierra de San Pedro Mártir in Baja California. Despite having been described for the first time in 1893 and a listing as threatened by Mexican authorities, no information is available on the ecology of this southernmost Tamiasciurus. We observed the ecology of Mearns's squirrels during 2004 and 2005. Mearns's squirrel apparently does not form larderhoards, known as middens, or leaf nests commonly built by other members of this genus. We observed Mearns's squirrels to feed heavily on tree seeds and fungi. We noted males with scrotal testes and a female in estrus in late spring. We did not observe eastern gray squirrels (Sciurus carolinensis), introduced to the western Sierra in 1946, within the areas that we searched for T. mearnsi. Mearns's squirrels might possess unique adaptations for their persistence in the dry, open forest of the Sierra de San Pedro Mártir.
• Pasch, B. S., & Koprowski, J. L. (2006). Annual cycles in body mass and reproduction of Chiricahua fox squirrels (Sciurus nayaritensis chiricahuae). SOUTHWESTERN NATURALIST, 51(4), 531-535.
• Pasch, B. S., & Koprowski, J. L. (2006). Annual cycles in body mass and reproduction of Chiricahua fox squirrels (Sciurus nayaritensis chiricahuae). Southwestern Naturalist, 51(4), 531-535.
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  Abstract: The Chiricahua fox squirrel (Sciurus nayaritensis chiricahuae) is an uncommon subspecies endemic to the Chiricahua Mountains of southeastern Arizona. We monitored annual cycles of body mass and reproduction to elucidate factors shaping the ecology of the sexes. Body mass of adult males did not fluctuate seasonally, although males tended to be heavier in winter. Body mass of adult females fluctuated seasonally, with lower body masses in summer than winter. Males and females did not differ in body mass in summer and fall, but females were heavier than males in winter and spring. Males with scrotal testes were found in the population during all seasons, but were especially prevalent in winter and spring. The majority of lactating females were present in spring and summer. Annual cycles in reproduction and body mass of Chiricahua fox squirrels are similar to more widespread species of tree squirrels, although males did not exhibit typical body mass fluctuations. Extreme spatial and temporal fluctuations of food experienced by Chiricahua fox squirrels might result in annual patterns in space use and body mass that differ from tree squirrels living in forests with a greater abundance of food.
• Pasch, B., & Koprowski, J. L. (2006). Sex differences in space use of Chiricahua fox squirrels. JOURNAL OF MAMMALOGY, 87(2), 380-386.
• Pasch, B., & Koprowski, J. L. (2006). Sex differences in space use of chiricahua fox squirrels. Journal of Mammalogy, 87(2), 380-386.
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  Abstract: Sex differences in reproductive investment influence space use patterns of many animals. In polygynous mammals, male space use reflects distribution of females and female space use reflects relative distribution of food. We used radiotelemetry to examine seasonal patterns of home-range size, overlap, and distance traveled by male and female Chiricahua fox squirrels (Sciurus nayaritensis chiricahuae) from 2002 to 2003. Male and female home-range and core-area size varied little between nonmating and mating seasons. Female core areas had a greater percentage overlap by males than by females during mating and nonmating seasons. Males traveled farther in the mating season and females showed little variation between seasons. Extreme spatial and temporal fluctuations of food experienced by Chiricahua fox squirrels may result in space use patterns that differ from those of tree squirrels living in forests with a greater abundance of food. © 2006 American Society of Mammalogists.
• Rushton, S. P., Wood, D. J., Lurz, P. W., & Koprowski, J. L. (2006). Modelling the population dynamics of the Mt. Graham red squirrel: Can we predict its future in a changing environment with multiple threats?. Biological Conservation, 131(1), 121-131.
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  Abstract: The Mt. Graham red squirrel (Tamiasciurus hudsonicus grahamensis; MGRS) is among the most critically endangered mammals in the United States and is isolated on the periphery of the species' range, potentially increasing its conservation priority. To investigate potential threats to the population and provide a tool for land managers, we developed a spatially explicit population dynamics model. We tested model predictions using available range-wide data from the literature and field work specific to the MGRS. A general model input data set using mean life history values overpredicted MGRS abundance. However, we found significant correlation with known squirrel abundance using a general data set with curtailed fecundity and survival. A model with MGRS-specific data provided the best fit to observed population size. We investigated potential impacts of two major threats to the MGRS: competition from introduced Abert's squirrels (Sciurus aberti) and increased levels of predation. Predation and particularly competition could have significant effects on the future population of the MGRS. Careful attention must be used to model the viability of fringe populations as peripheral populations can have a different life history than populations found in the range core. © 2006 Elsevier Ltd. All rights reserved.
• Rushton, S. P., Wood, D., Lurz, P., & Koprowski, J. L. (2006). Modelling the population dynamics of the Mt. Graham red squirrel: Can we predict its future in a changing environment with multiple threats?. BIOLOGICAL CONSERVATION, 131(1), 121-131.
• Edelman, A. J., & Koprowski, J. L. (2005). Diet and tree use of Abert's squirrels (Sciurus aberti) in a mixed-conifer forest. SOUTHWESTERN NATURALIST, 50(4), 461-465.
• Edelman, A. J., & Koprowski, J. L. (2005). Diet and tree use of Abert's squirrels (Sciurus aberti) in a mixed-conifer forest. Southwestern Naturalist, 50(4), 461-465.
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  Abstract: Abert's squirrels (Sciurus aberti) are reported to be dependent on ponderosa pine (Pinus ponderosa) forests for food, cover, and nest sites. Introduced Abert's squirrels in the Pinaleño Mountains of Arizona, however, occupy forests that contain little to no ponderosa pine. We documented diet and tree use of Abert's squirrels in mixed-conifer forests of the Pinaleno Mountains using observations of marked animals. Individuals ate similar food items as Abert's squirrels in ponderosa pine forests, including seeds, inner bark, buds, and fungi, but 5 conifer species were used as food sources. Douglas-fir (Pseudotsuga menziesii) and southwestern white pine (Pinus strobiformis) were the most frequently eaten conifer species. Abert's squirrels also were observed in all tree species. Our results suggest that the dependence of Abert's squirrels on ponderosa pine is not as strong as previously reported.
• Edelman, A. J., & Koprowski, J. L. (2005). Selection of drey sites by Abert's squirrels in an introduced population. JOURNAL OF MAMMALOGY, 86(6), 1220-1226.
• Edelman, A. J., & Koprowski, J. L. (2005). Selection of drey sites by Abert's squirrels in an introduced population. Journal of Mammalogy, 86(6), 1220-1226.
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  Abstract: Abert's squirrels (Sciurus aberti) are reported to depend on ponderosa pine (Pinus ponderosa) for food and nest sites. Introduced Abert's squirrels in the Pinaleño Mountains of Arizona, however, occupy mixed-conifer forests that contain almost no ponderosa pine (about 2%). We examined selection of drey sites in this introduced population. Dreys (i.e., spherical nests) were built adjacent to the trunk at 75% of the tree height. Dreys were found in 5 different conifer species and
• Koprowski, J. L. (2005). Annual cycles in body mass and reproduction of endangered Mt. Graham red squirrels. JOURNAL OF MAMMALOGY, 86(2), 309-313.
• Koprowski, J. L. (2005). Annual cycles in body mass and reproduction of endangered Mt. Graham red squirrels. Journal of Mammalogy, 86(2), 309-313.
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  Abstract: Annual cycles in life-history traits often are interpreted as adaptations. The Mt. Graham red squirrel (Tamiasdurus hudsonicus grahamensis) is an endangered species isolated in the Pinaleno Mountains of Arizona (United States) at the southernmost range terminus where the ecology is poorly known. I monitored annual cycles of reproduction and body mass in male and female Mt. Graham red squirrels. Males with scrotal testes were present during all months except October, with a peak in testis size in April. Lactating females were found from April to September. Male body mass was highest in winter and lowest in summer; females did not fluctuate seasonally in mass. Male body mass exceeded that of females during winter and was positively related to size of testes late in the breeding season. Annual cycles in reproduction and body mass of Mt. Graham red squirrels are similar to those of other red squirrels in similar life zones. © 2005 American Society of Mammalogists.
• Koprowski, J. L. (2005). The response of tree squirrels to fragmentation: A review and synthesis. Animal Conservation, 8(4), 369-376.
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  Abstract: Habitat fragmentation is often considered a major threat to biodiversity; however, our understanding of how fragmentation impacts populations is poor. Identifying appropriate models for such studies is difficult. Tree squirrels are dependent on mature forests for food, cover and nests; these are habitats that are being fragmented rapidly and that are easily defined by humans. Squirrels represent excellent models for study of fragmentation. The literature on tree squirrels was reviewed to glean data on density and home-range size in forest fragments. Sufficient data were available on four species (Sciurus carolinensis, S. niger, S. vulgaris, Tamiasciurus hudsonicus). Density was negatively related to fragment size for S. carolinensis and S. niger and marginally so for T. hudsonicus. Sciurus vulgaris did not exhibit this relationship. Home-range size was analysed for three species of Sciurus and was positively related to forest fragment size for S. carolinensis and S. niger. Again, only S. vulgaris did not to show this relationship. Sciurus vulgaris is rarely found in small forest fragments and is believed to be especially sensitive to fragmentation; other tree squirrels appear to be sensitive to fragmentation in more subtle ways. Home range compaction provides a mechanism by which densities may increase in small fragments. The demographic consequences resultant from the high densities of squirrels found in small woodlots are not known but may explain the forest damage, avian nest predation and reduced diversity often cited to occur in woodland fragments. © 2005 The Zoological Society of London.
• Koprowski, J. L. (2005). The response of tree squirrels to fragmentation: a review and synthesis. ANIMAL CONSERVATION, 8, 369-376.
• Koprowski, J. L., & Corse, M. C. (2005). Time budgets, activity periods, and behavior of Mexican fox squirrels. JOURNAL OF MAMMALOGY, 86(5), 947-952.
• Koprowski, J. L., & Corse, M. C. (2005). Time budgets, activity periods, and behavior of Mexican fox squirrels. Journal of Mammalogy, 86(5), 947-952.
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  Abstract: Resources that limit reproductive success differ between the sexes in many vertebrates. We used focal animal observations to determine sex-specific activity periods, time budgets, and movements of endemic Mexican fox squirrels (Sciurus nayaritensis chiricahuae) in montane forests of southeastern Arizona during June, August, and December 1994 and January 1995. Activity periods during summer were bimodal with peaks in morning and afternoon separated by a midday lull in activity; winter activity was unimodal. No sex differences were detected in activity periods, although males retired later than females in winter. Resting, feeding, and locomotion were the most common behaviors and accounted for >75% of activities of each sex. Activity by females did not differ between seasons. Males spent more time in locomotion in summer and more time feeding in winter than in other seasons. Differences in time budgets of the sexes suggest that males and females apportion daily activity to maximize access to resources that limit fitness of each sex. © 2005 American Society of Mammalogists.
• Koprowski, J. L., Alanen, M. I., & Lynch, A. M. (2005). Nowhere to run and nowhere to hide: Response of endemic Mt. Graham red squirrels to catastrophic forest damage. BIOLOGICAL CONSERVATION, 126(4), 491-498.
• Koprowski, J. L., Alanen, M. I., & Lynch, A. M. (2005). Nowhere to run and nowhere to hide: Response of endemic Mt. Graham red squirrels to catastrophic forest damage. Biological Conservation, 126(4), 491-498.
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  Abstract: A consequence of isolation is increased susceptibility to catastrophe. Insect damage to fragmented and isolated forests has the potential to serve as a catastrophic force; such damage has increased worldwide due to climate change and fire suppression policies. We examined the response of endangered endemic Mt. Graham red squirrels to catastrophic insect damage due to moths, beetles, and introduced aphids. Insects changed the forest environment significantly for the endemic squirrel by reducing basal area and stem densities of live stems, while increasing number and basal area of standing dead stems. Availability of two major foods, fungi and tree seeds, declined in insect-damaged forests relative to trends in undamaged forests. Numbers of Mt. Graham red squirrels declined precipitously in insect-damaged forests suggesting a catastrophe. Conservation options are limited in such situations. Forest-insect induced catastrophes are likely to become more common in the near future as forest health declines due to past management tactics and climate change. Prudent conservation measures include the anticipation of insect outbreaks and effective forest treatments to decrease likelihood of such catastrophes to species of precarious conservation status, while avoiding abrupt changes to critical habitat. © 2005 Elsevier Ltd. All rights reserved.
• Hutton, K. A., Koprowski, J. L., Greer, V. L., Alanen, M. I., Schauffert, C. A., & Young, P. J. (2003). Use of mixed-conifer and spruce-fir forests by an introduced population of Abert's squirrels (Sciurus aberti). SOUTHWESTERN NATURALIST, 48(2), 257-260.
• Hutton, K. A., Koprowski, J. L., Greer, V. L., Alanen, M. I., Schauffert, C. A., & Young, P. J. (2003). Use of mixed-conifer and spruce-fir forests by an introduced population of Abert's squirrels (Sciurus aberti). Southwestern Naturalist, 48(2), 257-260.
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  Abstract: Abert's squirrels (Sciurus aberti) are thought to depend on ponderosa pine (Pinus ponderosa) for food sources, cover, and nest sites. Records of Abert's squirrels using other food sources, forest types, and nest trees are rare. In the 1940s, Abert's squirrels were introduced to ponderosa pine forests on Mount Graham in the Pinaleño Mountains of southeastern Arizona. Since 1989, while studying Mount Graham red squirrels (Tamiasciurus hudsonicus grahamensis), we recorded Abert's squirrel sightings. In over 41,000 field-hours of studying Mount Graham red squirrels, we documented 498 Abert's squirrel sightings in both mixed-conifer and spruce-fir forests. Behaviors observed included feeding, collecting nest material, nest building, intraspecific chases, and interactions with the endangered red squirrels in this nontraditional habitat.
• McColgin, M. E., Brown, E. J., Bickford, S. M., Eilers, A. L., & Koprowski, J. L. (2003). Use of century plants (Agave palmeri) by coatis (Nasua narica). Southwestern Naturalist, 48(4), 722-725.
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  Abstract: We report observations and quantification of white nosed coatis (Nasua narica) using century plants (Agave palmeri) as a novel food source in Arizona. After observing a female coati eating in century plants, we inspected all flowering century plants in areas of coati activity for presence of scratch marks. Use of agaves by coatis was relatively common. Coatis climbed plants with large diameter at breast height relative to unscratched plants, but did not preferentially use agaves based on height or number of flower aggregations. Agaves in areas of high coati activity were more likely to possess scratch marks. Flowering agaves contain nectar, pollen, and arthropod species, all of which likely provide nutrition. The opportunistic foraging and willingness of coatis to experiment with unique food sources might partially explain the expansive distribution of the species under a wide variety of ecological conditions.
• Koprowski, J. L. (2002). Handling tree squirrels with a safe and efficient restraint. WILDLIFE SOCIETY BULLETIN, 30(1), 101-103.
• Koprowski, J. L. (2002). Handling tree squirrels with a safe and efficient restraint. Wildlife Society Bulletin, 30(1), 101-103.
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  Abstract: The most desirable handling techniques consider the safety of the study organism and the researcher, maximize efficiency by minimizing handling times, and reduce costs. I detail a handling device for tree squirrels that is safe, efficient, inexpensive, and portable. The restraint has been used to handle >3,500 individuals of 7 species of tree squirrel with a mortality rate of
• Schauffert, C. A., Koprowski, J. L., Greer, V. L., Alanen, M. I., Hutton, K. A., & Young, P. J. (2002). Interactions between predators and Mt. Graham red squirrels (Tamiasciurus hudsonicus grahamensis). SOUTHWESTERN NATURALIST, 47(3), 498-501.
• Schauffert, C. A., Koprowski, J. L., Greer, V. L., Alanen, M. I., Hutton, K. A., & Young, P. J. (2002). Interactions between predators and Mt. Graham red squirrels (Tamiasciurus hudsonicus grahamensis). Southwestern Naturalist, 47(3), 498-501.
• Koprowski, J. L., & Corse, M. C. (2001). Food habits of the Chiricahua fox squirrel (Sciurus nayaritensis chiricahuae). SOUTHWESTERN NATURALIST, 46(1), 62-65.
• Koprowski, J. L., & Corse, M. C. (2001). Food habits of the chiricahua fox squirrel (Sciurus nayaritensis chiricahuae). Southwestern Naturalist, 46(1), 62-65.
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  Abstract: The Chiricahua fox squirrel (Sciurus nayaritensis chiricahuae) is restricted to montane forests of the Chiricahua Mountains of southeastern Arizona. We used observations of focal animals to determine the diet of squirrels during summer and winter. Chiricahua fox squirrels feed heavily on seeds of trees, berries of mistletoe, and hypogeous fungi. Diets were most diverse in summer for males, whereas females did not demonstrate significant seasonality of diet. Daily diets were more diverse than reported for other tree squirrels. As in other tree squirrels, Chiricahua fox squirrels appear to be highly dependent on mature forest trees for food.
• Koprowski, J. L., & Perigo, N. (2000). Cooperative learning as a tool to teach vertebrate anatomy. American Biology Teacher, 62(4), 282-284.
• Koprowski, J. L. (1996). Natal philopatry, communal nesting, and kinship in fox squirrels and gray squirrels. JOURNAL OF MAMMALOGY, 77(4), 1006-1016.
• Koprowski, J. L. (1996). Natal philopatry, communal nesting, and kinship in fox squirrels and gray squirrels. Journal of Mammalogy, 77(4), 1006-1016.
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  Abstract: Tree squirrels (Sciuridae: Sciurini) are considered to be asocial; however, communal nesting is reported for most species. I examined the sociality of uniquely marked fox squirrels (Sciurus niger) and gray squirrels (S. carolinensis) to investigate interspecific patterns of natal philopatry, communal nesting, and kinship. Natal philopatry was female-biased in gray squirrels, resulting in the formation of kin clusters, but no fox squirrels remained in their natal areas. Adult male and female squirrels interacted less than expected, suggesting that the social systems of the sexes are separate. Communal nesting occurred in all seasons, but was most frequent in winter. Unrelated adult males commonly nested together in both species. However, adult female fox squirrels rarely nested in groups, although communal nests were common among female gray squirrels. Amicable behaviors were directed only toward closely related females (r = 0.5) within kin groups of gray squirrels; aggression was directed primarily at unrelated females. The female-female bond was important in the formation of groups in gray squirrels.
• KNEELAND, M. C., KOPROWSKI, J. L., & CORSE, M. C. (1995). POTENTIAL PREDATORS OF CHIRICAHUA FOX SQUIRRELS (SCIURUS-NAYARITENSIS-CHIRICAHUAE). SOUTHWESTERN NATURALIST, 40(3), 340-342.
• Koprowski, J. L. (1993). ALTERNATIVE REPRODUCTIVE TACTICS IN MALE EASTERN GRAY SQUIRRELS - MAKING THE BEST OF A BAD JOB. BEHAVIORAL ECOLOGY, 4(2), 165-171.
• Koprowski, J. L. (1993). BEHAVIORAL TACTICS, DOMINANCE, AND COPULATORY SUCCESS AMONG MALE FOX SQUIRRELS. ETHOLOGY ECOLOGY & EVOLUTION, 5(2), 169-176.
• Koprowski, J. L. (1993). SEX AND SPECIES BIASES IN SCENT-MARKING BY FOX SQUIRRELS AND EASTERN GRAY SQUIRRELS. JOURNAL OF ZOOLOGY, 230, 319-323.
• Koprowski, J. L. (1993). THE ROLE OF KINSHIP IN FIELD-INTERACTIONS AMONG JUVENILE GRAY SQUIRRELS (SCIURUS-CAROLINENSIS). CANADIAN JOURNAL OF ZOOLOGY-REVUE CANADIENNE DE ZOOLOGIE, 71(1), 224-226.
• Koprowski, J. L. (1993). The role of kinship in field interactions among juvenile gray squirrels (Sciurus carolinensis). Canadian Journal of Zoology, 71(1), 224-226.
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  Abstract: Adult eastern gray squirrels influence recruitment into local populations by directing aggression at juveniles and nonresidents. Amicable juvenile interactions occurred only between littermates, while aggression was directed almost exclusively at nonlittermates. Juveniles within their own natal areas dominated nonresident juveniles. Interactions among juveniles appear to be influenced by kinship and may be important in determining recruitment patterns in squirrel populations. -from Author
• Koprowski, J. L. (1992). DO ESTROUS FEMALE GRAY SQUIRRELS, SCIURUS-CAROLINENSIS, ADVERTISE THEIR RECEPTIVITY. CANADIAN FIELD-NATURALIST, 106(3), 392-394.
• Koprowski, J. L. (1992). Removal of copulatory plugs by female tree squirrels. Journal of Mammalogy, 73(3), 572-576.
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  Abstract: Copulatory plugs form in the vagina of females from the semen of male fox squirrels Sciurus niger and eastern gray squirrels S. carolinensis. Although copulatory plugs frequently are hypothesized to prevent the successful copulation of subsequent males, female tree squirrels often remove the plug within 30 s of copulating and either discard or consume it. -from Author
• Koprowski, J. L. (1991). RESPONSE OF FOX SQUIRRELS AND GRAY SQUIRRELS TO A LATE-SPRING EARLY-SUMMER FOOD SHORTAGE. JOURNAL OF MAMMALOGY, 72(2), 367-372.
• Koprowski, J. L. (1991). Response of fox squirrels and gray squirrels to a late spring-early summer food shortage. Journal of Mammalogy, 72(2), 367-372.
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  Abstract: Sciurus niger and S. carolinensis foraged more frequently, but less efficiently, during a year of fruit failure than during a typical year. Juvenile survival of both species was reduced during fruit failure, but adult survival remained high. Juvenile losses occurred during late June when weights of adults and juveniles were lower than in the year of typical fruit abundance. -from Author
• KOPROWSKI, J. L., ROSEBERRY, J. L., & KLIMSTRA, W. D. (1988). LONGEVITY RECORDS FOR THE FOX SQUIRREL. JOURNAL OF MAMMALOGY, 69(2), 383-384.

Presentations

• Koprowski, J. L. (2017, August). Significance of small mammals in ecological function and resilience (Plenary). South Asian Conference on Small Mammals. Kathmandu, Nepal: Asian Mammal Society.
• Koprowski, J. L. (2017, Entire Year). More than 20 presentations (posters and oral). AZ/NM Joint Annual Meeting of The Wildlife Society, American Society of Mammalogists, and The Wildlife Society.
• Koprowski, J. L. (2017, February). The future of Natural Resources and the Environmental Sciences: challenges create opportunities.. NRES Seminar Series. Reno, Nevada: Dept of Natural Resources and Environmental Sciences, University of Nevada-Reno.
• Koprowski, J. L. (2017, September). Knowledge gaps and canopy openings: the importance of Neotropical squirrels (Plenary).. Congresso Brasileiro de Mastozoologia. Pirenopolis, Brazil: Brasileiro de Mastozoologia.
• Koprowski, J. L. (2017, September). Montane mammals, conservation challenges, and climate change: consequences of forest degradation.. Darwin Lecture Series. Rio Claro, Sao Paolo, Brazil: Universidade Estadual Paulista Sao Paolo.
• Hale, S. L., Koprowski, J. L., & Archer, S. R. (2016, January). Invited Talk: Prairie Dogs: Rangeland Pests or Unexpected Allies in Grassland Management? In: Symposium: Rangeland Habitat, Wildlife Coexistence and Relationships. Soc. Range Management Annual Meetings. Corpus Christi, TX.
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  Approved for presentation on Feb 3, 2016
• Hale, S. L., Koprowski, J. L., & Archer, S. R. (2016, July). Re-assembling the pieces: The role of a recently reestablished keystone herbivore in restoring a degraded semidesert grassland ecosystem. North American Prairie Conference. Normal, IL.
• Hale, S., Koprowski, J. L., Archer, S. R., Hale, S., Koprowski, J. L., & Archer, S. R. (2016, February). Resuming a keystone role: the return of black-tailed prairie dogs to Arizona. Joint Annual Meeting, Arizona and New Mexico Chapters of The Wildlife Society and the American Fisheries Society. Flagstaff, AZ.
• Koprowski, J. L. (2016, Summer). >25 papers presented at Rodens et Spatium, American Society of Mammalogists, local and national meetings of The Wildlife Society. Rodens et Spatium, American Society of Mammalogists, local and national meetings of The Wildlife Society.
• Hale, S. L., Koprowski, J. L., & Archer, S. R. (2015, June). The potential role of a native grazer and keystone species in managing woody encroachment. American Society of Mammalogists 95th Annual Meeting. Jacksonville, FL.
• Koprowski, J. L. (2015, May). Climate change and montane mammals: challenges and opportunities.. Invited. Adam Mickiewicz University, Poznan, Poland..
• Koprowski, J. L. (2015, November). Montane mammals, conservation challenges, and climate change: consequences of forest degradation.. Invited. Dept. of Wildlife Ecology & Conservation, University of Florida..
• Koprowski, J. L. (2015, November). The future of Fisheries and Wildlife. Invited. Dept of Fisheries and Wildlife, Oregon State University.
• Koprowski, J. L. (2015, Summer). 4 invited talks at Kyoto University each dealing with conservation of rare and endangered species, climate change, Mt. Graham red squirrels. Presentations made to Kyoto Museum, Kyoto University Wildlife Research Institute, Primate Research Institute, Taxonomic Research Group. Kyoto University, Kyoto, Japan.
• Koprowski, J. L. (2015, Throughout the year). Coauthor of 27 presentations. AZ-NM Joint Annual Meeting of TWS, National meetings of The Wildlife Society, American Society of Mammalogists, International Meetings of Intl Wildlife Mgmt Conference, Intl Colloquium Arboreal Squirrels.
• Koprowski, J. L. (2014, All). Coauthor of 24 presentations and posters at professional conferences. AZ/NM Joint Annual Meeting of The Wildlife Society, American Society of Mammalogists, The Wildlife Society, Society of Conservation Biology, Ecological Society of America.
• Koprowski, J. L. (2014, December). Challenges for mountain mammals: it is lonely at the top. Invited. Beijing, China: Chinese Academy of Science.
• Koprowski, J. L. (2014, February). The future of fish & wildlife conservation: viewing challenge as opportunities. Invited. Blacksburg, Virginia: Virginia Tech.
• Koprowski, J. L. (2014, January). Saga of the Mt. Graham red squirrel: building bridges to move from a monitoring to a research. Invited. Moscow, Idaho: University of Idaho..
• Koprowski, J. L. (2014, January). The future of fish & wildlife sciences: viewing challenges as opportunities. Invited. Moscow, Idaho: University of Idaho.
• Koprowski, J. L. (2014, July). It’s lonely at the top: the saga of the Mt. Graham red squirrel harbinger of global change.. Inivited. Cork, Ireland: University of Cork, Ireland.
• Koprowski, J. L. (2013, April). Saga of the Mt. Graham red squirrel: building bridges to move from a monitoring to a research program.. Invited Presentation at University of Montana. Missoula, MT: University of Montana Wildlife Biology Program.
• Koprowski, J. L. (2013, April). The future of wildlife biology: viewing challenges as opportunities. Invited Presentation at University of Montana. Missoula, MT: University of Montana Wildlife Biology Program.
• Koprowski, J. L. (2013, Nov). Climate change and biodiversity in the mountains: opportunities for students, scientists and society.. Invited Presentation at NW Agriculture & Forestry University. Yangling, Shaanxi, PR of China: Dept of Entomology and Plant Protection.
• Koprowski, J. L. (2013, Year). Coauthor/author of 21 scientific presentations. American Society of Mammalogists, International Mammalogy Congress, The Wildlife Society, Joint Annual Meeting of AZ-NM TWS,.
• Chen, H., & Koprowski, J. (2012, May). Effects of roads on wildlife in Arizona: how far have we traveled?. 3rd Madrean Archipelago Conference. Tucson.
• Hale, S., Koprowski, J., & Hicks, H. (2012, May). A review of black-tailed prairie dog reintroduction strategies and site selection: Arizona reintroduction. 3rd Madrean Archipelago Conference. Tucson.
• Ketcham, S., & Koprowski, J. (2012, May). Impacts of wildfire on wildlife in Arizona: a synthesis. 3rd Madrean Archipelago Conference. Tucson.
• Koprowski, J. L. (2012, February). Conservation of the arboreal squirrels: how well are we doing?. 6th International Arboreal Squirrel Conference. Kyoto, Japan.
• Koprowski, J. L. (2012, February). Ecosystem services and the value of arboreal squirrels in our changing world: multiple roles within the forest. 6th International Arboreal Squirrel Conference. Kyoto, Japan.
• Koprowski, J. L. (2012, February). Space use without the constraints of larderhoarding: Mearns's squirrel in the high sierra of Baja. AZ/NM Wildlife Society Annual Conference. Phoenix, AZ.
• Koprowski, J. L. (2012, November). Conservation challenges in a changing world: lessons from endangered montane squirrels. Korean Wildlife Conference. Seoul, South Korea.
• Koprowski, J. L. (2012, October). It s lonely at the top: Conservation challenges for the montane endemic Mt. Graham red squirrel. Willamette University, Department of Biology. Salem, OR.
• Koprowski, J. L., & Chen, H. (2012, February). Road effects on movements and occupancy of red squirels. 6th International Arboreal Squirrel Conference. Kyoto, Japan.
• Koprowski, J. L., & Derbridge, J. (2012, February). Impact of introduced Abert s squirrels on the endangered Mount Graham red squirrel. 6th International Arboreal Squirrel Conference. Kyoto, Japan.
• Koprowski, J. L., & Derbridge, J. (2012, November). Using experimental removals and stable isotope analysis of diet to determine mechanisms of competition between an endangered tree squirrel and a non-native competitor. Annual Meeting of The Wildlife Society. Portland,OR: The Wildlife Society.
• Koprowski, J. L., & Greer, V. (2012, February). Update on the Mt. Graham red squirrel research program. AZ/NM Wildlife Society Annual Conference. Phoenix, AZ.
• Koprowski, J. L., & Hale, S. (2012, February). Status of the reintroduction of prairie dogs in Arizona. AZ/NM Wildlife Society Annual Conference. Phoenix, AZ.
• Koprowski, J. L., & Jessen, T. (2012, February). Hairtube sampling for detection and identification of small mammals. 6th International Arboreal Squirrel Conference. Kyoto, Japan.
• Koprowski, J. L., & Ketcham, S. (2012, February). Impact of introduced Abert's squirrels on native Arizona Gray Squirrels. AZ/NM Wildlife Society Annual Conference. Phoenix, AZ.
• Koprowski, J. L., & Merrick, M. (2012, February). Dispersal and settlement in an endangered forest obligate: influence of behavior and forest structure. 6th International Arboreal Squirrel Conference. Kyoto, Japan.
• Koprowski, J. L., & Merrick, M. (2012, June). Exploring the role of individual behavior and natal experience in dispersal of an endangeredforest obligate. American Society of Mammalogists Annual Meeting. Reno, NV.
• Koprowski, J. L., & Merrick, M. (2012, November). Exploring the role of individual behavior and natal experience in dispersal of an endangeredforest obligate. Annual Meeting of The Wildlife Society. Portland,OR: The Wildlife Society.
• Koprowski, J. L., & Munroe, K. (2012, February). Predicting mating systems in tree squirrels using social organization models of ground-dwellingsciurids. 6th International Arboreal Squirrel Conference. Kyoto, Japan.
• Koprowski, J. L., & Posthumus, E. (2012, June). Can red squirrel (Tamiasciurus hudsonicus) middens affect species diversity?. American Society of Mammalogists Annual Meeting. Reno, NV.
• Koprowski, J. L., & Posthumus, E. (2012, November). Can red squirrel (Tamiasciurus hudsonicus) middens affect species diversity?. Annual Meeting of The Wildlife Society. Portland,OR: The Wildlife Society.
• Koprowski, J. L., Huynh, H., Bertolino, S., Lurz, P., Williams, G., Thompson, C., & McAlpine, D. (2012, February). The even darker side of the eastern gray squirrel (Sciurus carolinensis): a review of global introductions, invasion biology, and pest management strategies. 6th International Arboreal Squirrel Conference. Kyoto, Japan.
• Koprowski, J. L., Kawamichi, M., Merrick, M., Hazama, K., & Kawamichi, T. (2012, February). Communal nest use by cliff chipmunks Tamias dorsalis. 6th International Arboreal Squirrel Conference. Kyoto, Japan.
• Koprowski, J. L., Thorington, R., Steele, M., Whatton, J., & Bohaska, P. (2012, June). The Sciuridae: a definitive reference. American Society of Mammalogists Annual Meeting. Reno, NV.
• Koprowski, J., Doumas, S., Merrick, M., Oleson, B., Posthumus, E., Jessen, T., & Gwinn, R. (2012, May). It s lonely at the top: biodiversity at risk to loss from climate change. 3rd Madrean Archipelago Conference. Tucson.
• Merrick, M., Koprowski, J., & Wilcox, C. (2012, May). Into the third dimension: benefits of incorporating LiDAR data in wildlife habitat models. 3rd Madrean Archipelago Conference. Tucson.
• Posthumus, E., & Koprowski, J. (2012, February). Can red squirrel middens influence species diversity?. 6th International Arboreal Squirrel Conference. Kyoto, Japan.
• Chen, H., & Koprowski, J. (2011, February). Do roads serve as boundary of home ranges of Mt. Graham red squirrels?. AZ/NM Wildlife Society Annual Conference. Hon-dah, AZ.
• Chen, H., & Koprowski, J. (2011, November). Barrier effects of roads: boundary of home ranges of endangered Mt. Graham red squirrels. Annual Meeting of The Wildlife Society. Kona, Hawaii.
• Derbridge, J., & Koprowski, J. (2011, November). Does larderhoarding by endangered Mount Graham red squirrels facilitate interspecific competition with non-native Abert s squirrels?. Annual Meeting of The Wildlife Society. Kona, Hawaii.
• Hale, S., & Koprowski, J. (2011, November). Population and Behavioral Ecology of Black-Tailed Prairie Dogs. Annual Meeting of The Wildlife Society. Kona, Hawaii.
• Jessen, R., & Koprowski, J. (2011, February). Habitat use and Associations of Neotropical Tree Squirrels: Pygmy Feet Fill Big Conservation Shoes. AZ/NM Wildlife Society Annual Conference. Hon-dah, AZ.
• Jessen, R., & Koprowski, J. (2011, June). Habitat associations and use by Neotropical tree squirrels in the Peruvian Amazon. American Society of Mammalogists Annual Meeting. Portland,OR.
• Jessen, R., & Koprowski, J. (2011, November). Habitat Associations And Use By Neotropical Tree Squirrels In The Peruvian Amazon. Annual Meeting of The Wildlife Society. Kona, Hawaii.
• Jessen, T., & Koprowski, J. (2011, June). Hairtube sampling for detection and identification of small mammals. American Society of Mammalogists Annual Meeting. Portland,OR.
• Jessen, T., & Koprowski, J. (2011, May). Novel method for detection and identification of small mammals. Annual Meeting of The Wildlife Society. Hon-dah, AZ.
• Jessen, T., & Koprowski, J. (2011, November). Hairtube Sampling For Detection And Identification Of Small Mammals. Annual Meeting of The Wildlife Society. Kona, Hawaii.
• Ketcham, S., & Koprowski, J. (2011, November). Differential Response of a Native and an Introduced Squirrel to a Mosaic of Burn Severities. Annual Meeting of The Wildlife Society. Kona, Hawaii.
• Koprowski, J. (2011, November). A Primer on the Endangered Mt. Graham Red Squirrel: Current Status and Threats. Annual Meeting of The Wildlife Society. Hon-dah, AZ.
• Koprowski, J. L. (2011, June). Conservation of the endangered Mt. Graham red squirrel: much more than Scopes vs. Squirrels. American Society of Mammalogists Annual Meeting. Portland,OR.
• Koprowski, J. L. (2011, March). Conservation challenges in forests: Tree squirrels as the miner's canary. Departmental Seminar at Towson University, Department of Biological Sciences. Towson, MD.
• Koprowski, J. L. (2011, November). Endangered species: Does the North American Model need to change?. National Student Leadership Group, The Wildlife Soceity. Kona, Hawaii.
• Lara, N., & Koprowski, J. (2011, June). A stranger in the genus Tamiasciurus: life history and behavior of Mearns s squirrels in Baja California, Mexico. American Society of Mammalogists Annual Meeting. Portland,OR.
• Merrick, M., & Koprowski, J. (2011, August). Dispersal and settlement in an endangered forest obligate: multiple approaches. AZ/NM Wildlife Society Annual Conference. Hon-dah, AZ.
• Merrick, M., & Koprowski, J. (2011, June). Dispersal and settlement in an endangered forest obligate: multiple approaches. American Society of Mammalogists Annual Meeting. Portland,OR.
• Merrick, M., & Koprowski, J. (2011, November). Investigating age-specific habitat use during natal dispersal. Annual Meeting of The Wildlife Society. Kona, Hawaii.
• Munroe, K., & Koprowski, J. (2011, June). Social behaviors and genetic structure in a population of round tailed ground squirrels (Xerospermophilus tereticaudus): what you see isn t always what you get. American Society of Mammalogists Annual Meeting. Portland,OR.
• Posthumus, E., & Koprowski, J. (2011, November). Can red squirrel middens influence species diversity?. Annual Meeting of The Wildlife Society. Kona, Hawaii.
• Scobie, E., Merrick, M., Koprowski, J., & Greer, V. (2011, June). The subterranean life of an arboreal squirrel: burrow use by endangered Mt. Graham red squirrels. American Society of Mammalogists Annual Meeting. Portland,OR.
• Thorington, J. R., Koprowski, J., Steele, M., Whatton, J., & Bohaska, P. (2011, June). Squirrels of the world: the world of squirrels. American Society of Mammalogists Annual Meeting. Portland,OR.

Poster Presentations

• Nichols, M., Koprowski, J. L., Fehmi, J. S., & Abercrombie, S. T. (2018, spring). Small mammalian herbivores inhibit grass establishment in an arid shrubland. Society for Range Management 71st annual meeting. Sparks, NV: Society for Range Management.
• Nichols, M. H., Koprowski, J. L., Fehmi, J. S., & Abercrombie, S. T. (2017, June). Small Mammalian Herbivores Decrease Herbaceous Cover in Shrub Invaded Grasslands.. American Society of Mammologists (97th Annual Meeting).. Moscow, ID..
• Nichols, M. H., Koprowski, J. L., Fehmi, J. S., & Abercrombie, S. T. (2017, October). Native Lagomorphs Inhibit Grass Establishment in a Semi-Arid Shrubland. Research Insights in Semiarid Ecosystems Symposium (14th Annual Meeting). Tucson, AZ.
• Hale, S. L., Koprowski, J. L., & Archer, S. R. (2015, April). Can a small, native grazer manage woody encroachment after reestablishment?. Earth Week. University of Arizona.