@article{cove_kays_bontrager_bresnan_lasky_frerichs_klann_lee_crockett_crupi_et al._2021, title={SNAPSHOT USA 2019: a coordinated national camera trap survey of the United States}, volume={102}, ISSN={["1939-9170"]}, DOI={10.1002/ecy.3353}, abstractNote={With the accelerating pace of global change, it is imperative that we obtain rapid inventories of the status and distribution of wildlife for ecological inferences and conservation planning. To address this challenge, we launched the SNAPSHOT USA project, a collaborative survey of terrestrial wildlife populations using camera traps across the United States. For our first annual survey, we compiled data across all 50 states during a 14-week period (17 August - 24 November of 2019). We sampled wildlife at 1509 camera trap sites from 110 camera trap arrays covering 12 different ecoregions across four development zones. This effort resulted in 166,036 unique detections of 83 species of mammals and 17 species of birds. All images were processed through the Smithsonian's eMammal camera trap data repository and included an expert review phase to ensure taxonomic accuracy of data, resulting in each picture being reviewed at least twice. The results represent a timely and standardized camera trap survey of the USA. All of the 2019 survey data are made available herein. We are currently repeating surveys in fall 2020, opening up the opportunity to other institutions and cooperators to expand coverage of all the urban-wild gradients and ecophysiographic regions of the country. Future data will be available as the database is updated at eMammal.si.edu/snapshot-usa, as well as future data paper submissions. These data will be useful for local and macroecological research including the examination of community assembly, effects of environmental and anthropogenic landscape variables, effects of fragmentation and extinction debt dynamics, as well as species-specific population dynamics and conservation action plans. There are no copyright restrictions; please cite this paper when using the data for publication.}, number={6}, journal={ECOLOGY}, author={Cove, Michael V. and Kays, Roland and Bontrager, Helen and Bresnan, Claire and Lasky, Monica and Frerichs, Taylor and Klann, Renee and Lee, Thomas E., Jr. and Crockett, Seth C. and Crupi, Anthony P. and et al.}, year={2021}, month={Jun} }
 @article{kumar_zimova_sparks_mills_2020, title={Snow-mediated plasticity does not prevent camouflage mismatch}, volume={194}, ISSN={["1432-1939"]}, DOI={10.1007/s00442-020-04680-2}, abstractNote={Global reduction in snow cover duration is one of the most consistent and widespread climate change outcomes. Declining snow duration has severe negative consequences for diverse taxa including seasonally color molting species, which rely on snow for camouflage. However, phenotypic plasticity may facilitate adaptation to reduced snow duration. Plastic responses could occur in the color molt phenology or through behavior that minimizes coat color mismatch or its consequences. We quantified molt phenology of 200 wild snowshoe hares (Lepus americanus), and measured microhabitat choice and local snow cover. Similar to other studies, we found that hares did not show behavioral plasticity to minimize coat color mismatch via background matching; instead they preferred colder, snow free areas regardless of their coat color. Furthermore, hares did not behaviorally mitigate the negative consequences of mismatch by choosing resting sites with denser vegetation cover when mismatched. Importantly, we demonstrated plasticity in the initiation and the rate of the molt and established the direct effect of snow on molt phenology; greater snow cover was associated with whiter hares and this association was not due to whiter hares preferring snowier areas. However, despite the observed snow-mediated plasticity in molt phenology, camouflage mismatch with white hares on brown snowless ground persisted and was more frequent during early snowmelt. Thus, we find no evidence that phenotypic plasticity in snowshoe hares is sufficient to facilitate adaptive rescue to camouflage mismatch under climate change.}, number={3}, journal={OECOLOGIA}, author={Kumar, Alexander V and Zimova, Marketa and Sparks, James R. and Mills, L. Scott}, year={2020}, month={Nov}, pages={301–310} }
 @article{lafferty_zimova_clontz_hacklander_mills_2019, title={Noninvasive measures of physiological stress are confounded by exposure}, volume={9}, ISBN={2045-2322}, DOI={10.1038/s41598-019-55715-5}, abstractNote={Abstract Glucocorticoids and glucocorticoid metabolites are increasingly used to index physiological stress in wildlife. Although feces is often abundant and can be collected noninvasively, exposure to biotic and abiotic elements may influence fecal glucocorticoid metabolite (FGM) concentrations, leading to inaccurate conclusions regarding wildlife physiological stress. Using captive snowshoe hares ( Lepus americanus ) and simulated environmental conditions, we evaluated how different realistic field conditions and temporal sampling constraints might influence FGM concentrations using an 11-oxoetiocholanolone-enzyme immunoassay. We quantified how fecal pellet age (i.e., 0–6 days), variable summer temperatures, and precipitation affected FGM concentrations. Fecal pellet age had a strong effect on FGM concentrations (β Age = 0.395, s.d. = 0.085; β 2 Age = −0.061, s.d. = 0.012), which were lowest at the beginning and end of our exposure period (e.g., mean day6 = 37.7 ng/mg) and typically highest in the middle (mean day3 = 51.8 ng/mg). The effect of fecal pellet age on FGM concentrations varied across treatments with warm-dry and cool-wet conditions resulting in more variable FGM concentrations relative to control samples. Given the confounding effects of exposure and environmental conditions, if fresh fecal pellet collection is not an option, we encourage researchers to develop a temporally consistent sampling protocol to ensure all samples are exposed to similar environmental conditions.}, journal={SCIENTIFIC REPORTS}, author={Lafferty, Diana J. R. and Zimova, Marketa and Clontz, Lindsay and Hacklander, Klaus and Mills, L. Scott}, year={2019} }
 @article{zimova_mills_nowak_2016, title={High fitness costs of climate change-induced camouflage mismatch}, volume={19}, ISSN={["1461-0248"]}, DOI={10.1111/ele.12568}, abstractNote={Anthropogenic climate change has created myriad stressors that threaten to cause local extinctions if wild populations fail to adapt to novel conditions. We studied individual and population-level fitness costs of a climate change-induced stressor: camouflage mismatch in seasonally colour molting species confronting decreasing snow cover duration. Based on field measurements of radiocollared snowshoe hares, we found strong selection on coat colour molt phenology, such that animals mismatched with the colour of their background experienced weekly survival decreases up to 7%. In the absence of adaptive response, we show that these mortality costs would result in strong population-level declines by the end of the century. However, natural selection acting on wide individual variation in molt phenology might enable evolutionary adaptation to camouflage mismatch. We conclude that evolutionary rescue will be critical for hares and other colour molting species to keep up with climate change.}, number={3}, journal={ECOLOGY LETTERS}, author={Zimova, Marketa and Mills, L. Scott and Nowak, J. Joshua}, year={2016}, month={Mar}, pages={299–307} }
 @article{zimova_mills_lukacs_mitchell_2014, title={Snowshoe hares display limited phenotypic plasticity to mismatch in seasonal camouflage}, volume={281}, ISSN={["1471-2954"]}, DOI={10.1098/rspb.2014.0029}, abstractNote={As duration of snow cover decreases owing to climate change, species undergoing seasonal colour moults can become colour mismatched with their background. The immediate adaptive solution to this mismatch is phenotypic plasticity, either in phenology of seasonal colour moults or in behaviours that reduce mismatch or its consequences. We observed nearly 200 snowshoe hares across a wide range of snow conditions and two study sites in Montana, USA, and found minimal plasticity in response to mismatch between coat colour and background. We found that moult phenology varied between study sites, likely due to differences in photoperiod and climate, but was largely fixed within study sites with only minimal plasticity to snow conditions during the spring white-to-brown moult. We also found no evidence that hares modify their behaviour in response to colour mismatch. Hiding and fleeing behaviours and resting spot preference of hares were more affected by variables related to season, site and concealment by vegetation, than by colour mismatch. We conclude that plasticity in moult phenology and behaviours in snowshoe hares is insufficient for adaptation to camouflage mismatch, suggesting that any future adaptation to climate change will require natural selection on moult phenology or behaviour.}, number={1782}, journal={PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES}, author={Zimova, Marketa and Mills, L. Scott and Lukacs, Paul M. and Mitchell, Michael S.}, year={2014}, month={May} }