New publication highlights differential response to fire by an endemic and introduced squirrel

New research by KCRL alum Nate Gwinn and Dr. K. highlights the differential response to fire by the endangered, endemic Mt. Graham red squirrels (Tamiasciurus fremonti grahamensis) and introduced Abert’s squirrels (Sciurus aberti) in the Pinaleño Mountains. Nate’s Master’s research quantified the use of burned and and unburned forest by both species via radio telemetry and feeding sign transects.  Abert’s squirrels were more likely to use burned areas for foraging and nesting, whereas native Mt. Graham red squirrels tended to avoid burned areas, suggesting that increased fire frequency and severity benefits the introduced species while effectively limiting habitat available to the native species.

Read more about it here:

Gwinn, R. N. and J. L. Koprowksi. 2017. Differential response to fire by an introduced and an endemic species complicates endangered species conservation. Hystrix doi:10.4404/hystrix-27.2-11447:1-7.



KCRL PhD student Mauricio Vela-Vargas awarded Phoenix Zoo Conservation and Science Grant

Congrats to KCRL PhD student Mauricio Vela-Vargas on being awarded the Phoenix Zoo’s Conservation and Science Grant!  Mauricio’s proposal, entitled ‘Andean-Bear-human conflict areas in the Chingaza Massif, Colombia: hotspots, drivers and potential solutions’ will support his dissertation research on understanding the current status, habitat, and variables associated with human-bear conflict in Colombia.

Read more about Mauricio’s work:

Learn more about the Phoenix Zoo’s Global Conservation Program:



Three KCRL students awarded grants for conservation biology from T&E Inc.!

Big congrats to KCRL master’s students Allie Burnett and Colin Brocka and PhD student Brian Blais for being awarded research grants for conservation biology from T & E Inc.

T & E Inc. is a non-profit  corporation dedicated to the appreciation and preservation of native flora and fauna of New Mexico, Arizona, and northern Mexico.  T & E’s conservation biology grants serve to encourage students in Conservation Biology and related fields, by offering financial grants especially for field research and public education. Special emphasis is placed on research benefiting threatened and endangered species.

Read more about Allie, Colin, and Brian’s funded research projects below:

Brian Blais: What are the spatial and behavioral dynamics in a conservation translocated population? A viability case study for threatened narrow-headed gartersnakes, Thamnophis rufipunctatus

Allie Burnett: Effects of woody encroachment on anti-predator behavior and communication

Colin Brocka: Terrestrial ecology of the endangered Sonoran tiger salamander


Dr. K weighs in on Huff Post piece about a Christmas light-thieving squirrel

A Seattle homeowner caught a squirrely culprit red pawed as it stole her Christmas light bulbs and then proceeded to bury them about the neighborhood.  Dr. K was called is as the resident squirrel expert on squirrel-Christmas decoration interactions.  While Dr. K points out that the behavior is a normal part of squirrel winter preparations and food storage, he said there is also a slim chance that “we simply have style-conscious squirrels.”

Read the full story here:


PhD candidate Jonathan Derbridge and KCRL alum Yeong-Soek Jo’s work on the status of invasive nutria and muskrat in South Korea has been accepted for publication

PhD candidate Jonathan Derbridge has been collaborating with KCRL alum Dr. Yeong-Soek Jo (Texas Tech University, National Institute of Biological Resources, Bucheon-si, South Korea) on reviewing the history of invasion and current status of invasive nutria and muskrat in South Korea.  Their work has recently been published in the journal Wetlands. See below for details.

Congrats Jonathan and Yeong-Soek!

Jo, Y. S., J. J. Derbridge, and J. T. Baccus. 2016. History and current status of invasive nutria and common muskrat in Korea. Wetlands DOI 10.1007/s13157-016-0867-z

Drivers of natal dispersal, causes of endangerment – two new KCRL publications fill key knowledge gaps in Mt. Graham red squirrel ecology and conservation

Two new publications by KCRL wildlife biologist Melissa Merrick and postdoc alum Emily Goldstein shed light upon important population processes that are unique to Mt. Graham red squirrels: natal dispersal, fecundity, and survivorship.  Compared to other North American red squirrel populations, Mt. Graham red squirrels exhibit sex-biased natal dispersal with mean dispersal distances that are up to 9x greater.  Juvenile natal dispersal distance is driven by food resources, the body condition of mothers, and individual behavior traits, which may provide a flexible feedback mechanism to adjust local sex ratios and density depending on environmental conditions. Adult Mt. Graham red squirrels also suffer much higher mortality, with adult life expectancies mirroring those of highly hunted squirrel populations.  Low adult survivorship means that most adult females only get to reproduce once in their lifetimes – a critical limiting factor in population recovery.

Read both papers:

Goldstein, E. A., M. J. Merrick, and J. L. Koprowski. 2017. Functional semelparity drives population dynamics and endangers a peripheral population. Biological Conservation 205:52-59.

Merrick, M. J., and J. L. Koprowski 2016. Altered natal dispersal at the range periphery: the role of behavior, resources, and maternal condition. Ecology and Evolution 00:1-15. doi: 101002/ece3.2612.

New publication offers evidence of natal habitat preference induction in a habitat specialist

New research from KCRL member Melissa Merrick’s dissertation research on natal dispersal in the endangered Mt. Graham red squirrel provides evidence that even habitat specialists tend to settle in places that look like home.  The decision of where to settle following natal dispersal is one of the most important decisions young animals make in their lifetimes.  Preference for habitat features that resemble those of the natal area by dispersing individuals is known as Natal Habitat Preference Induction (NHPI) and may be an important mechanism for habitat selection during natal dispersal, particularly in the face of rapid environmental change.  While most studies of NHPI demonstrate natal habitat preference by individuals born in contrasting vegetation community-types, we found evidence of NHPI in an endangered forest obligate that inhabits one vegetation community-type.  This finding has implications for understanding how juveniles in this population decide where to settle and for current and planned habitat management and restoration plans.

Read it here:

Merrick MJ, Koprowski JL. 2016 Evidence of natal habitat preference induction within one habitat type. Proc. R. Soc. B 283: 20162106.