المؤلفون: Ganz, Taylor R., DeVivo, Melia T., Wirsing, Aaron J., Bassing, Sarah B., Kertson, Brian N., Walker, Savanah L., Prugh, Laura R.

المصدر: Bulletin of the Ecological Society of America, 2024 Apr 01. 105(2), 1-5.

الوصول الحر: https://www.jstor.org/stable/48765815Test

المؤلفون: Grinath, Joshua B, Larios, Loralee, Prugh, Laura R, Brashares, Justin S, Suding, Katharine N

المصدر: Oikos. 128(7)

مصطلحات موضوعية: Life on Land, arid grassland, biodiversity, burrowing rodents, community composition, disturbance, endangered species, rainfall gradient, resource availability, soil properties, Ecology

الوصف: Understanding processes that determine biodiversity is a fundamental challenge in ecology. At the landscape scale, physical alteration of ecosystems by organisms, called ecosystem engineering, enhances biodiversity worldwide by increasing heterogeneity in resource conditions and enhancing species coexistence across engineered and non-engineered habitats. Engineering–diversity relationships can vary along environmental gradients due to changes in the amount of physical structuring created by ecosystem engineering, but it is unclear how this variation is influenced by the responsiveness of non-structural abiotic properties to engineering. Here we show that environmental gradients determine the capacity for engineering to alter resource availability and species diversity, independent of the magnitude of structural change produced by engineering. We created an experimental rainfall gradient in an arid grassland where rodents restructure soils by constructing large, long-lasting burrows. We found that greater rainfall increased water availability and productivity in both burrow and inter-burrow habitats, causing a decline in local (alpha) plant diversity within both of these habitats. However, increased rainfall also resulted in greater differences in soil resources between burrow and inter-burrow habitats, which increased species turnover (beta diversity) across habitats and stabilized landscape-level (gamma) diversity. These responses occurred regardless of rodent presence and without changes in the extent of physical alteration of soils by rodents. Our results suggest that environmental gradients can influence the effects of ecosystem engineering in maintaining biodiversity via resource heterogeneity and species turnover. In an era of rapid environmental change, accounting for this interaction may be critical to conservation and management.

وصف الملف: application/pdf

الوصول الحر: https://escholarship.org/uc/item/3f50v3zvTest

المؤلفون: Borg, Bridget L., Arthur, Stephen M., Falke, Jeffrey A., Prugh, Laura R.

المصدر: Arctic, 2021 Mar 01. 74(1), 51-66.

الوصول الحر: https://www.jstor.org/stable/27088556Test

المؤلفون: Sullender, Benjamin K., Cunningham, Calum X., Lundquist, Jessica D., Prugh, Laura R.

المصدر: Oikos ; volume 2023, issue 10 ; ISSN 0030-1299 1600-0706

الوصف: Snowpack dynamics have a major influence on wildlife movement ecology and predator–prey interactions. Specific snow properties such as density, hardness, and depth determine how much an animal sinks into the snowpack, which in turn drives both the energetic cost of locomotion and predation risk. Here, we quantified the relationships between five field‐measured snow variables and snow track sink depths for widely distributed predators (bobcats Lynx rufus , cougars Puma concolor , coyotes Canis latrans , wolves C. lupus ) and sympatric ungulate prey (caribou Rangifer tarandus , white‐tailed deer Odocoileus virginianus , mule deer O. hemionus , and moose Alces alces ) in interior Alaska and northern Washington, USA. We first used generalized additive models to identify which snow metrics best predicted sink depths for each species and across all species. Next, we used breakpoint regression to identify thresholds of support for the best‐performing predictor of sink depth for each species (i.e. values wherein tracks do not sink appreciably deeper into the snow). Finally, we identified ‘danger zones,' wherein snow impedes the mobility of ungulates more than carnivores, by comparing sink depths relative to hind leg lengths among predator–prey pairs. Near‐surface (0–20 cm) snow density was the strongest predictor of sink depth across species. Thresholds of support occurred at near‐surface snow densities between 220–310 kg m – 3 for predators and 300–410 kg m – 3 for prey, and danger zones peaked at intermediate snow densities (200–300 kg m – 3 ) for eight of the ten predator–prey pairs. These results can be used to link predator–prey relationships with spatially explicit snow modeling outputs and projected future changes in snow density. As climate change rapidly reshapes snowpack dynamics, these danger zones provide a useful framework to anticipate likely winners and losers of future winter conditions.

الإتاحة: https://doi.org/10.1111/oik.09925Test

المؤلفون: Greaves, Heather E, Boelman, Natalie T, Brinkman, Todd J, Liston, Glen E, Prugh, Laura R, Reinking, Adele K

المساهمون: NASA

المصدر: Environmental Research Letters ; volume 18, issue 2, page 025006 ; ISSN 1748-9326

الوصف: As Arctic and boreal regions rapidly warm, the frequency and seasonal timing of hazardous driving conditions on all-season Arctic-boreal roads are likely to change. Because these roads link remote Arctic areas to the rest of the North American road system, climate change may substantially affect safety and quality of life for northern residents and commercial enterprises. To gain insight into future hazardous driving conditions, we built Random Forest models that predict the occurrence of hazardous driving conditions by linking snow, ice, and weather simulated by a spatially explicit modeling system (SnowModel) to archived road condition reports from two highly trafficked all-season northern roads: the Dalton Highway (Alaska, USA) and Dempster Highway (Yukon, Canada). We applied these models to downscaled future climate trajectories for the study period of 2006–2100. We estimated future trends in the frequency and timing of icy, wet-icy, and snowy road surfaces, blowing and drifting snow, and high winds. We found that as the climate warms, and the portion of the year when snow and ice occur becomes shorter, overall frequency of snow storms and ice- and snow-related driving hazards decreased. For example, the mean number of days per year when roads are covered in snow or ice decreased by 51 d (−21%) on the Dalton Highway between the 2006–2020 and 2081–2100 time periods. However, the intensity of storms was predicted to increase, resulting in higher mean annual storm wind speeds (Dalton +0.56 m s −1 [+17%]) and snowfall totals (Dalton +0.3 cm [+36%]). Our models also predicted increasing frequency of wet-icy driving conditions during November, December, January, and February, when daylength is short and hazardous conditions may be more difficult to perceive. Our findings may help road managers and drivers adapt their expectations and behaviors to minimize accident risk on Arctic-boreal roads in the future.

الإتاحة: https://doi.org/10.1088/1748-9326/acb5b1Test

المؤلفون: Nuñez, Tristan A., Prugh, Laura R., Hille Ris Lambers, Janneke

المساهمون: National Science Foundation

المصدر: Trends in Ecology & Evolution ; volume 38, issue 7, page 654-665 ; ISSN 0169-5347

مصطلحات موضوعية: Ecology, Evolution, Behavior and Systematics

الإتاحة: https://doi.org/10.1016/j.tree.2023.02.005Test
https://api.elsevier.com/content/article/PII:S0169534723000344?httpAccept=text/xmlTest
https://api.elsevier.com/content/article/PII:S0169534723000344?httpAccept=text/plainTest

المؤلفون: Ganz, Taylor R., Bassing, Sarah B., DeVivo, Melia T., Gardner, Beth, Kertson, Brian N., Satterfield, Lauren C., Shipley, Lisa A., Turnock, Benjamin Y., Walker, Savanah L., Abrahamson, Derek, Wirsing, Aaron J., Prugh, Laura R.

المصدر: Ecological Applications; Jul2024, Vol. 34 Issue 5, p1-22, 22p

مستخلص: Large terrestrial mammals increasingly rely on human‐modified landscapes as anthropogenic footprints expand. Land management activities such as timber harvest, agriculture, and roads can influence prey population dynamics by altering forage resources and predation risk via changes in habitat, but these effects are not well understood in regions with diverse and changing predator guilds. In northeastern Washington state, USA, white‐tailed deer (Odocoileus virginianus) are vulnerable to multiple carnivores, including recently returned gray wolves (Canis lupus), within a highly human‐modified landscape. To understand the factors governing predator–prey dynamics in a human context, we radio‐collared 280 white‐tailed deer, 33 bobcats (Lynx rufus), 50 cougars (Puma concolor), 28 coyotes (C. latrans), and 14 wolves between 2016 and 2021. We first estimated deer vital rates and used a stage‐structured matrix model to estimate their population growth rate. During the study, we observed a stable to declining deer population (lambda = 0.97, 95% confidence interval: 0.88, 1.05), with 74% of Monte Carlo simulations indicating population decrease and 26% of simulations indicating population increase. We then fit Cox proportional hazard models to evaluate how predator exposure, use of human‐modified landscapes, and winter severity influenced deer survival and used these relationships to evaluate impacts on overall population growth. We found that the population growth rate was dually influenced by a negative direct effect of apex predators and a positive effect of timber harvest and agricultural areas. Cougars had a stronger effect on deer population dynamics than wolves, and mesopredators had little influence on the deer population growth rate. Areas of recent timber harvest had 55% more forage biomass than older forests, but horizontal visibility did not differ, suggesting that timber harvest did not influence predation risk. Although proximity to roads did not affect the overall population growth rate, vehicle collisions caused a substantial proportion of deer mortalities, and reducing these collisions could be a win–win for deer and humans. The influence of apex predators and forage indicates a dual limitation by top‐down and bottom‐up factors in this highly human‐modified system, suggesting that a reduction in apex predators would intensify density‐dependent regulation of the deer population owing to limited forage availability. [ABSTRACT FROM AUTHOR]

: Copyright of Ecological Applications is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

المؤلفون: Procko, Michael, Winder, Samantha G., Wood, Spencer A., Sevigny, Michael, Collins, Dylan G., Alves, Molly, Prugh, Laura R.

المصدر: Ecosphere; Jun2024, Vol. 15 Issue 6, p1-24, 24p

مصطلحات موضوعية: ELK, WILDLIFE management, ECOLOGICAL integrity, ANIMAL populations, RECREATION

مصطلحات جغرافية: WASHINGTON (D.C.)

مستخلص: Recreation is known to impact wildlife by displacing and sometimes contributing to the extirpation of sensitive species, underscoring a need for policies that balance wildlife and recreation. This is especially pressing when Indigenous rights necessitate ecological integrity and sustainable populations of wildlife throughout traditional territories. In the Cascade Mountain Range of Washington, USA, Indigenous harvest of elk (Cervus canadensis) is declining, concurrent with increases in recreation. Yet, the nature and magnitude of the effects of recreation on elk are unknown, which prevents land managers from developing informed policies regarding recreation and wildlife management. Here, we use camera traps alongside visitation models that incorporate geolocated social media to quantify the impacts of recreation on elk in western Washington. Random forest models show elk detection rates are relatively constant at low levels of recreation (0–11 people/day), but decrease by over 41% when recreation increases from 12 to 22 people/day. Activity overlap analysis also revealed a shift toward increased evening activity by elk at cameras with higher‐than‐average recreation (∆ = 0.70, 95% CI = 0.61–0.88; χ2 = 7.79, p = 0.02). Generalized additive modeling confirms that elk are more crepuscular or nocturnal at camera locations with more than 10 hiker detections per day. We compare methods for estimating recreation, showing model‐based estimates are more informative than camera‐based estimates. This indicates that recreational intensity along and in the immediate vicinity of trails may be a better predictor of impacts on wildlife than camera‐based estimates that quantify recreational intensity at specific locations along trails. We stress the importance of examining the impacts of recreation on wildlife across multiple spatiotemporal scales and underscore how novel approaches can provide land managers valuable tools to develop management strategies that balance recreation and wildlife. We hope that our work can also serve as a strong example of collaboration between universities, state agencies, and sovereign Indigenous nations toward the broader goal of mitigating the negative impacts of recreation on wildlife. [ABSTRACT FROM AUTHOR]

: Copyright of Ecosphere is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

المؤلفون: Kreling, Samantha E. S., Reese, Ellen M., Cavalluzzi, Olivia M., Bozzi, Natalee B., Messinger, Riley, Schell, Christopher J., Long, Robert A., Prugh, Laura R.

المساهمون: Division of Environmental Biology, University of Washington, Animal Welfare Institute

المصدر: Molecular Ecology ; ISSN 0962-1083 1365-294X

الوصف: Linear barriers pose significant challenges for wildlife gene flow, impacting species persistence, adaptation, and evolution. While numerous studies have examined the effects of linear barriers (e.g., fences and roadways) on partitioning urban and non‐urban areas, understanding their influence on gene flow within cities remains limited. Here, we investigated the impact of linear barriers on coyote ( Canis latrans ) population structure in Seattle, Washington, where major barriers (i.e., interstate highways and bodies of water) divide the city into distinct quadrants. Just under 1000 scats were collected to obtain genetic data between January 2021 and December 2022, allowing us to identify 73 individual coyotes. Notably, private allele analysis underscored limited interbreeding among quadrants. When comparing one quadrant to each other, there were up to 16 private alleles within a single quadrant, representing nearly 22% of the population allelic diversity. Our analysis revealed weak isolation by distance, and despite being a highly mobile species, genetic structuring was apparent between quadrants even with extremely short geographic distance between individual coyotes, implying that Interstate 5 and the Ship Canal act as major barriers. This study uses coyotes as a model species for understanding urban gene flow and its consequences in cities, a crucial component for bolstering conservation of rarer species and developing wildlife friendly cities.

الإتاحة: https://doi.org/10.1111/mec.17427Test

المؤلفون: Ganz, Taylor R., DeVivo, Melia T., Wirsing, Aaron J., Bassing, Sarah B., Kertson, Brian N., Walker, Savanah L., Prugh, Laura R.

المساهمون: Washington Department of Fish and Wildlife, University of Washington, Rocky Mountain Elk Foundation, National Science Foundation

المصدر: Ecology ; volume 105, issue 4 ; ISSN 0012-9658 1939-9170

الوصف: To manage predation risk, prey navigate a dynamic landscape of fear, or spatiotemporal variation in risk perception, reflecting predator distributions, traits, and activity cycles. Prey may seek to reduce risk across this landscape using habitat at times and in places when predators are less active. In multipredator landscapes, avoiding one predator could increase vulnerability to another, making the landscape of fear difficult to predict and navigate. Additionally, humans may shape interactions between predators and prey, and induce new sources of risk. Humans can function as a shield, providing a refuge for prey from human‐averse carnivores, and as a predator, causing mortality through hunting and vehicle collisions and eliciting a fear response that can exceed that of carnivores. We used telemetry data collected between 2017 and 2021 from 63 Global Positioning System‐collared elk ( Cervus canadensis ), 42 cougars ( Puma concolor ), and 16 wolves ( Canis lupus ) to examine how elk habitat selection changed in relation to carnivores and humans in northeastern Washington, USA. Using step selection functions, we evaluated elk habitat use in relation to cougars, wolves, and humans, diel period (daytime vs. nighttime), season (summer calving season vs. fall hunting season), and habitat structure (open vs. closed habitat). The diel cycle was critical to understanding elk movement, allowing elk to reduce encounters with predators where and when they would be the largest threat. Elk strongly avoided cougars at night but had a near‐neutral response to cougars during the day, whereas elk avoided wolves at all times of day. Elk generally used more open habitats where cougars and wolves were most active, rather than altering the use of habitat structure depending on the predator species. Elk avoided humans during the day and ~80% of adult female mortality was human caused, suggesting that humans functioned as a “super predator” in this system. Simultaneously, elk leveraged the human shield against wolves but not ...

الإتاحة: https://doi.org/10.1002/ecy.4255Test