Journal of Wildlife Management最新文献

The New Mexico jumping mouse (Zapus luteus) is a federally endangered species reliant on riparian areas in the southwestern United States. Restoration of habitat in riparian areas would reduce threats to the species and enable recovery, and quantifying specific habitat features that support occupancy of the species throughout its range will inform management of these areas. With this objective, we surveyed for New Mexico jumping mice for 3 days each at 113 sites across Arizona and New Mexico and measured conditions of the vegetation, soil, and streams. We then constructed occupancy models to estimate detection probability and identify habitat variables important in predicting use by the species. We found that occupancy of New Mexico jumping mice was best predicted by high variability in vegetation height, tall vegetation, variation in soil moisture, stream gradient, and stream width. New Mexico jumping mice were more likely to occupy sites with consistently high soil moisture, vegetation height >60 cm with variable vegetation structure and wide streams with low gradients. Additionally, we assessed which vegetation variables were most useful in describing occupied and unoccupied sites. Reducing the number of vegetation variables that need to be measured to adequately assess conditions important to the New Mexico jumping mouse could help optimize survey protocols. This information can provide guidelines for local conditions that could be targeted for conservation and restoration to favor occupancy of the species.

Noninvasive survey methods, such as camera trapping and acoustic monitoring, offer valuable tools for large-scale wildlife surveys because of their efficacy, cost efficiency, and minimal disturbance to animals. We evaluated the use of camera traps and acoustic detectors, including low-cost AudioMoth detectors, for surveying northern and southern flying squirrels Glaucomys sabrinus and G. volans, respectively, across the state of New York, USA. We manually classified acoustic data to species and used morphological data collected from camera trap images to predict species identity using a random forest classifier. We evaluated the efficacy of each technique and estimated the probability of detection using a multi-method occupancy framework and latency to detection. Both methods offered a high probability of detection and low latency to detection, but we were unable to reliably differentiate between the two species from camera traps in most cases (73% of detection events). Further, while acoustic detectors and camera traps had similar detection rates during spring, the performance of acoustics when using primarily low-cost detectors declined in summer, while camera trap performance remained stable. Integrating both methods may enhance large-scale survey efforts, providing robust data for conservation strategies. We recommend further optimization of these techniques, such as extending camera deployment durations, shortening camera trigger delays, and improving acoustic detector sensitivity to improve accuracy of species identification and overall survey effectiveness.

Understanding diet quality is essential for wildlife ecology and management, especially in Mediterranean ecosystems where forage quality varies markedly throughout the year. Fecal nitrogen is a widely used non-invasive indicator of ungulate diet quality, though its collection and analysis can be resource-intensive. To address this, environmental proxies like the normalized difference vegetation index (NDVI) and bioclimatic indices (e.g., real bioclimatic intensity [RBI], standardized precipitation-evapotranspiration index [SPEI]) have been proposed as scalable alternatives. This study evaluated the spatial and intra-annual variation of fecal nitrogen in a fenced Mediterranean estate in central Spain and its relationship with NDVI at different scales and bioclimatic indices. Fecal nitrogen showed significant intra-annual variability aligned with seasonal changes in forage quality but no spatial differences across local habitats. The NDVI derived from herbaceous vegetation, open forests, and whole-estate scales explained monthly fecal nitrogen variation, whereas NDVI from Mediterranean woodlands did not. We did not find evidence of relationships between fecal nitrogen and RBI or SPEI. These findings highlight that the fecal nitrogen–NDVI relationship is scale-dependent and that herbaceous NDVI is a reliable proxy for tracking diet quality in Mediterranean red deer populations.

Estimating spatial and temporal patterns in abundance is often a goal of ecological studies and can be useful for informing management decisions, such as determining the optimal placement of wildlife protection zones. However, estimating abundance can be difficult in practice, especially over large areas, because of imperfect detection, where individuals are present but not detected because of either availability or observer error. Several methods for estimating abundance that account for imperfect detection exist but can be logistically challenging to implement. We present a simpler approach to some of the more commonly used techniques for estimating the abundance of marine wildlife over space and time from unstructured aerial surveys. This approach combines a spatial model for count data with auxiliary information on detection probability obtained from small-scale or previous studies. We employ generalized linear models and generalized additive models with spatial habitat covariates to illustrate this approach using maximum-likelihood with free, open-source statistical software. This framework is intended to be accessible and flexible, requiring lower survey costs and less computation time than other alternatives for estimating abundance. Indeed, our simulation results show that this approach can reduce computation times, while appropriately characterizing uncertainty, compared to a Bayesian approach. We also present R code for our approach using an example of estimating Florida manatee (Trichechus manatus latirostris) abundance in Indian River County in Florida, USA. This approach could be applied to other study systems and marine wildlife species using unstructured aerial surveys.

Ungulates in temperate regions can experience high mortality during severe winters, which poses significant ecological and economic challenges for wildlife managers. To mitigate these effects, emergency winter-feeding programs are often implemented, although their effectiveness remains uncertain. In response to high snowfall and prolonged winter conditions in 2023, the Utah Division of Wildlife Resources implemented an emergency feeding program aimed at reducing mortality among mule deer (Odocoileus hemionus). We evaluated the impact of this effort by monitoring survival of 102 mule deer with global positioning system (GPS) collars across fed (27 adults, 21 fawns) and non-fed groups (45 adults, 9 fawns). Additionally, we assessed the body condition of adult females using estimates of ingesta-free body fat percentage via ultrasonography. The program distributed 305 metric tons of feed at a cost of $213,500, with additional logistical expenses totaling $122,246. Of the latter amount, volunteers contributed $94,534. Adult females without supplemental feeding had a faster rate of fat loss (β = −0.01, 95% CI = −0.009–−0.001) and low overwinter survival (58%; SE = 0.07) compared to the fed group (81%; SE = 0.07). Fawn survival in the fed group was 53% (SE = 0.11), while no fawns survived in the non-fed group. Malnutrition was the primary cause of mortality in both groups. Key factors contributing to increased survival in the fed deer included the timely and sustained feeding, ration composition, strategic site selection, and distribution methods at feeding sites. Logistical support from volunteers was crucial for the timely implementation of the program. The program incurred a total expenditure of $335,746, resulting in the survival of an estimated 1,099 mule deer at an average cost of $305.50 per deer. Although the program successfully enhanced overwinter survival, particularly among the most vulnerable group—fawns—the substantial costs involved underscore the necessity to carefully balance such interventions against their economic viability.

Habitat suitability models (HSMs) play an important role in conservation planning by identifying areas for habitat management and guiding surveys for population discovery and monitoring. The wood turtle Glyptemys insculpta is a riverine turtle that uses both riparian and upland environments. Habitat loss and degradation have resulted in range-wide declines of this species throughout the United States. Previous HSMs have been developed for wood turtles; however, no published HSM we are aware of exists for their range in the midwestern United States (including parts of Iowa, Michigan, Minnesota, and Wisconsin), or has incorporated terrestrial, aquatic, and climatic variables. We developed a wood turtle HSM across their distribution in the midwestern United States using Random Forest. Modeling units consisted of 800–1,000-m stream segments and a 300-m buffer surrounding each segment. We obtained verified occurrence records from 2000–2024 from state agencies, concurrent research projects, and the community science platform iNaturalist, resulting in 1,833 segments with documented occurrence to serve as model training data. Assessment metrics indicated good model performance (area under the operator curve = 0.92, true skill statistic = 0.6704). Stream order, width, and gradient were the most influential aquatic variables, with lower stream order, lower widths, and lower gradient being associated with higher probability of occurrence. The most influential terrestrial variables were proportion of still water in the terrestrial environment, landscape condition index, and topographic ruggedness index, with lower proportion of still water in the terrestrial environment, moderate to high landscape condition, and lower topographic ruggedness being associated with higher occurrence probability. The majority of stream segments (68.4%) with ≥0.8 probability of occurrence currently lack documented wood turtle populations, allowing for prioritization of these streams for future surveys. These results can assist with guiding habitat management and restoration efforts in their midwestern United States range.

While wind energy is a key sector of domestic energy production for the United States, operation of wind turbines directly and indirectly adversely affects certain species of birds and bats. The cumulative effect of wind turbine strikes can have both biological and regulatory consequences, and, in some cases, delay permitting and construction or affect ongoing operations. Technology can help quantify and minimize these effects, but the pace of development, acceptance, and adoption of technological solutions is slow. Although adopting cost-effective technologies may reduce negative effects on wildlife and help achieve both energy production and conservation goals, consensus is lacking among developers, regulators, and the conservation community regarding how to define technology effectiveness and acceptance and how to develop a standardized process for doing so. Removing barriers to technology advancement requires deviating from the status quo. Changes include 1) creating incentives to mitigate impacts, 2) establishing options for research as mitigation, 3) rethinking how research is funded, 4) increasing stakeholder coordination, and 5) increasing the efficiency of research and development. We recommend the creation of a national framework to establish clear criteria and protocols for technology evaluation and adoption.

Cambridge Bay, Nunavut, hosts Canada's largest Arctic Char Salvelinus alpinus commercial fishery with waterbody-specific quotas managed under one Integrated Fisheries Management Plan that emphasizes ecosystem-based management and the need to understand bycatch in the fishery. Bycatch reporting in the fishery, however, remains deficient. In this study, we report on fish, invertebrate, and marine mammal bycatch recorded in logbooks from 2012–2018 at two commercial waterbodies fished using weirs (Halokvik, Jayko) and two fished using gillnets (Surrey, Ekalluk) in multiple Arctic char habitats (rivers, lakes, estuaries). Arctic Char not retained for commercial purposes (discards or those kept for subsistence) comprised the greatest amount of bycatch. Other bycatch included seven fish species (n = 633), one crab species (n = 5), and two seal species (n = 11). Weir fisheries had minimal non-target bycatch, with Halokvik reporting none and Jayko only one species. Gillnet fisheries exhibited the highest bycatch diversity, particularly at the Surrey estuarine fishery. Significant inter-annual variation in the amount of non-target bycatch was also observed at three of the four waterbodies. These findings offer insights for ecosystem-based management for this fishery, while providing a baseline for future monitoring.

Wildlife health and conservation are increasingly recognized as key to improving human, animal, and environmental health (One Health) and detecting and addressing threats such as altered distribution and transmission of zoonotic diseases due to climate change. Wildlife, and therefore wildlife management, are crucial for the livelihood and well-being of people in the Canadian North, a vast geographic area with low population density and socio-economic disparities, which can make widespread program implementation challenging. We analyzed and compared 4 case studies on collaborative programs on wildlife health management from 4 distinct jurisdictions in the Canadian North: the Yukon, chronic wasting disease surveillance in ungulates; Northwest Territories, rabies in arctic fox (Vulpes lagopus); Nunavut, foodborne diseases in harvested wildlife; and Nunavik, Québec, ringed seal (Pusa hispida) health and Trichinella in walrus (Odobenus rosmarus). The case studies differed in whether they focused on a specific pathogen, transmission route, or health of a specific wildlife population. Despite these differences, 3 main themes were common to all case studies: collaboration, infrastructure limitations, and adaptation. Collaboration promotes greater community buy-in and investment as community members help shape the program and is key to long-term success, sustainability, and local relevance. Laboratory infrastructure and human resource capacity are limited in most regions, highlighting the importance of collaboration among Indigenous-managed boards and organizations, community members, government agencies at multiple levels, academic institutions, and the national wildlife health non-governmental organization (Canadian Wildlife Health Cooperative). Examples of adaptations include capitalizing on wildlife harvest for fur and food to obtain samples for surveillance, developing regulations to train and permit veterinary paraprofessionals and community volunteers to facilitate co-existence of pets and people with wildlife reservoirs of rabies, jointly developing regulations to prevent introduction of non-endemic diseases, and adapting hunting locations based on the results of wildlife disease monitoring. Combining Indigenous knowledge and a One Health framework is fundamental to co-managing zoonotic and food-borne diseases in wildlife while respecting Indigenous ways of life. The case studies provide meaningful examples of collaboration and solutions to address complex problems at the One Health interface and to use a holistic and community-based approach to facilitate the creation of regionally acceptable and culturally relevant programs, with better outcomes for wildlife, human, and environmental health.