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Articles in this issue include using fecal environmental DNA methods to detect river otters, recommendations for translocation New Mexico jumping mice and scouting wild pigs using thermal drones.
For the first time, wildlife managers have detected the fungal pathogen that causes white-nose syndrome—a disease that has devastated North American bat populations since 2006—in Nevada. The U.S. National Park Service detected the fungus on a California leaf-nosed bat (Macrotus californicus) in Lake Mead National Recreation Area in Clark County during routine monitoring. “We knew it was a matter of time before [white-nose syndrome] arrived in Nevada and we have been vigilantly surveying bats for many years now, not only for this fungus but also to track their population trends,” said Jonathan Young, a staff specialist at the Nevada Department of Wildlife (NDOW). The fungus that causes white-nose syndrome, Pseudogymnoascus destructans, is primarily spread by bat-to-bat contact during hibernation. “Nevada’s bats are incredibly important, and this fungus could have serious implications for their conservation.” said Young. NDOW is working to protect bat habitats, particularly abandoned mines, to prevent unintentional spread of the fungus on human clothing and equipment and will continue monitoring to determine how widespread the fungus is.
The impact of a deadly new strain of bird flu, the growing integration of Indigenous knowledge and the use of tools like drones and bear spray in wildlife management are the research topics wildlife readers were most interested to read in 2025.
Metrics have revealed that the top read studies published in The Wildlife Society’s journals vary widely—some of them are still gaining significant tractions several years after publication. At least three of these articles were also featured on the 2024 list of top-read TWS journal studies.
Here are the top 10, most viewed full-text papers from TWS journals read in 2025:
Whether through external media or through our own award-winning communications team, TWS is making sure that the science of wildlife professionals makes it to your peers, the general public and beyond. Thank you to all of the authors and readers of this year’s top 10 list!
Are you publishing your science in a Society-owned journal? For many nonprofit, professional societies like TWS, publications are crucial to the mission and operations of the organization. By publishing in a Society-owned journal you are not only contributing to the advancement of science but also supporting the organizations that help advocate for science, provide resources to professionals, uphold professional ethics, build stronger communities, and recruit the next generation of professionals.
Imperiled Bonelli’s eagles experienced a baby boom, increasing in numbers thanks to the anthropause lockdown during the COVID-19 pandemic. Bonelli’s eagles (Aquila fasciata) have been declining in Spain in recent years due to human-driven factors such as electrocution, poaching, and poisoning. At least one Spanish province has listed them as endangered as a result. But new research published in Biological Conservation tracking long-term productivity showed that in 2020, the year that the COVID-19 pandemic hit the world, the species had the highest average number of chicks born per pair in 31 years of monitoring. “The lockdown coincided with critical stages of reproduction: the end of the incubation period and the entire time the chicks were growing in the nest,” said José María Gil and Marcos Moleón, the researchers who led the study, in a press release. “The absence of disturbance by humans in the vicinity of the nesting sites resulted in exceptional reproduction for our times, but reflects what must have been normal before human pressure reached current levels.”
Wildlife collisions have increased by 50%, according to the latest report issued by the U.S. Department of Transportation Federal Highway Administration, and many more go uncounted. These accidents injure tens of thousands of people and cost more than $10 billion each year, all while killing up to 2 million large animals including white-tailed deer (Odocoileus virginianus) and endangered species from the Hawaiian goose (Branta sandvicensis) to the San Joaquin kit fox (Vulpes macrotis mutica).
Wildlife crossings—overpasses, underpasses, and associated fencing—have the potential to cut collisions by as much as 97% along movement corridors. Despite their effectiveness, federal funding hasn’t kept up with demand. The Wildlife Crossings Pilot Program, created under the 2021 Infrastructure Investment and Jobs Act, found that the need far exceeded available cash, leaving many proposals unfunded.
That funding gap is the focus of a bill recently introduced in Congress. Reps. Don Beyer (D-VA) and Ryan Zinke (R-MT) have authored the Wildlife Road Crossings Program Reauthorization Act. This proposed bipartisan legislation would renew the Wildlife Crossings Pilot Program as a long-term initiative while extending its funding through 2031. If passed, the bill could reshape how the nation addresses wildlife-vehicle collisions and habitat connectivity by providing consistent, reliable funding.
Funding cuts put wildlife and lives at risk
Approximately 70% of Montana drivers have been in a wildlife collision. Montana has the second highest risk of wildlife collisions in the nation. “For many, it’s not a question of if they will get into a collision with wildlife on U.S. 93; it’s a question of when,” said TWS member Renee Callahan, executive director of Animal Road Crossing (ARC) Solutions, a company involved in wildlife crossing design and implementation.
The Confederated Salish and Kootenai Tribes in collaboration with the Montana Department of Transportation scheduled construction on two significant wildlife crossing projects in the state—the Post Creek Hill and the Ninepipe Eagle Pass Trail on U.S. Route 93— in 2026 and 2027, respectively. But both have been abruptly scaled back due to funding cuts.
The Confederated Salish and Kootenai Tribes secured over $80 million in federal grants for wildlife overpasses along Route 93 in the Ninepipe area, including a $74.9 million grant that would have covered more than 80% of the project. That grant was rescinded when the “Big Beautiful Bill” passed. Two other Infrastructure Investment and Jobs Act grants for the project remain intact: a $30.5-million Nationally Significant Federal Lands and Tribal Projects award and an $8.6-million Wildlife Crossings Pilot Program award. However, the Montana Department of Transportation said construction costs have exceeded available funding. The agency has been forced to scale back their vision for the highway, reducing the Post Creek Hill project and limiting the Ninepipe Eagle Pass Trail project to the Eagle Pass Trail and Route 93 Wildlife Overpass portions of the planned work.
The overall size of the Ninepipe and Eagle Pass Trail project area has been reduced due to funding cuts. Credit: Montana Department of Transportation
“Many of these projects are planned years, sometimes decades, in advance and require hundreds of hours to coordinate and plan,” Callahan said. “Canceling a year before the project begins doesn’t just mean the project doesn’t get done. It means all that time is wasted.”
It’s the kind of setback that underscores why long-term, reliable investment is critical and why supporters say the new Wildlife Road Crossings Program Reauthorization Act can’t come soon enough.
A potential bipartisan solution
The Wildlife Road Crossings Program Reauthorization Act of 2025 would continue and expand the program established under the Infrastructure Investment and Jobs Act, removing its “pilot” status and formalizing a federal commitment to reducing wildlife-vehicle collisions and restoring habitat connectivity. Eligible projects would include crossing structures that go over or under highways, associated fencing to guide animals to safe passage points, and other tools and strategies that help transportation agencies identify and integrate wildlife considerations early in the planning process.
“This bill locks in the progress we started, keeps the funding flowing to the states and Tribes that need it most, and ensures Montana families don’t have to risk their lives or lose the wildlife we all cherish driving to work or school,” said Zinke.
If enacted, the bill would provide $200 million annually from Fiscal Year 2026–2031—$1 billion total—for wildlife crossing projects nationwide. It includes a full federal cost share for Tribal projects, eliminating non-federal match requirements and setting aside dedicated technical assistance funding to help Tribes access the program.
The months of October, November, and December make up 41% of all animal collision insurance claims with an estimated 650,000 incidents. Credit: retiredinwasaga
The bill would also authorize a minimum 0.5% of program funds for the Federal Highway Administration to modernize wildlife collision data and strengthen standards for wildlife passage at bridges, culverts and other roadway structures. Better monitoring would address an essential step toward addressing a longstanding challenge: inconsistent, imprecise and under-reported national data on wildlife-vehicle collisions that makes it difficult to pinpoint where mitigation is most needed.
“Our bill would invest in these solutions by reauthorizing the Wildlife Crossings Program and allowing it to continue funding wildlife-friendly transportation infrastructure that saves lives, lowers costs, and improves road safety for drivers and wildlife alike,” said Beyer.
If passed, the bill could help fund projects in states with some of the highest wildlife-vehicle collision rates, such as Montana and West Virginia, helping ensure that projects aimed at protecting both motorists and wildlife can move forward without disruption.
“Wildlife crossings save lives and are good for healthy herds,” Zinke said. TWS CEO Ed Arnett, who worked on the getting the original pilot project into legislation, agrees. “This is a no-brainer and clear win-win for people and wildlife. The Wildlife Society commends Representatives Zinke and Beyer for their leadership on this issue and support for the wildlife crossings program.”
Fences and other human-made barriers are leading to the collapse of a wildebeest migration route in Kenya’s Greater Mara Ecosystem. New maps published in the Atlas of Ungulate Migration by ecologists at the Smithsonian National Zoo and Conservation Biology Institute have revealed that wildlife connectivity is being severely curtailed in large natural areas in western Kenya, on the northern end of the Serengeti. “Over the past 10 years, the Mara ecosystem has undergone profound changes and offers a warning to other grassland ecosystems facing similar human pressures,” said Jared Stabach, a Smithsonian ecologist who built the maps, in a press release. These barriers don’t only impact blue wildebeest (Connochaetes taurinus), but other ungulates as well. When these migration routes are lost, they aren’t easily regained as animals learn these paths over generations. The lost of ancestral routes could also make it harder for ungulates to find vital resources in times of scarcity, carrying population level effects.
Cliff Bampton’s career in wildlife management traces the origin of the profession. From graduate school dropout to chief of the North Carolina Wildlife Resources Commission’s Division of Game, Bampton helped define modern wildlife management.
In this episode of “Our Wild Lives,” host Katie Perkins sits down with long-time TWS member, Cliff Bampton. The conversation spans from his early adulthood experiences trapping black bears (Ursus americanus) in the Adirondack Mountains to his decades of experience at the North Carolina Wildlife Resources Commission and Ducks Unlimited.
Despite the challenges he faced such as trouble in school, colorblindness, office politics and more, Bampton leaves a legacy rooted in hard work, compromise and cooperation.
“Our Wild Lives” is The Wildlife Society’s weekly podcast, sharing compelling stories from wildlife professionals doing critical work around the world. Your hosts, Katie Perkins and Ed Arnett, of The Wildlife Society, bring you thought-provoking conversations with leading experts and emerging voices.
New episodes are released weekly wherever you get your podcasts. Please email comms@wildlife.org with feedback or future episode suggestions.
More than 60,000 African penguins have died in just eight years due to collapsing sardine stocks. Researchers estimate that 95% of the African penguins (Spheniscus demersus) within the species’ two most crucial breeding colonies—Dassen Island and Robben Island—died between 2004 and 2012. The researchers also believe that the majority of the deaths occurred during the penguins’ annual molting process, a period of around three weeks where the birds replace their worn-out feathers with new ones. During this time, the birds must remain on land and can’t hunt, relying on fat reserves so they don’t starve. “If food is too hard to find before they molt or immediately afterwards, they will have insufficient reserves to survive the fast,” said Richard Sherley, a conservation biologist at the University of Exeter. The Pacific sardine (Sardinops sagax) has also seen immense declines over the same period due to overfishing and climate change. Certain types of fishing have been banned near key breeding colonies and some conservationists on the ground are helping to improve fledging success by building artificial nests, managing for predators and hand-rearing rescued chicks. The species was listed as Critically Endangered by the International Union for the Conservation of Nature in 2024.
As porcupine numbers decrease across the West, wildlife managers are racing to understand the trend. The creatures faced widespread persecution in the 1900s from the timber industry, which didn’t look kindly upon their habit of chewing on trees. Thousands of porcupines (Erethizon dorsatum) were poisoned and many states offered bounties. These bounties mostly ended in 1979, but porcupines have struggled to recover in the decades since. TWS member Erik Beever and others are now studying porcupine numbers to confirm this apparent trend. “We’re wondering whether the species is either increasing or declining without anybody even knowing,” the U.S. Geological Survey ecologist told High Country News. In places like California, it’s possible that rodenticides left around illegal marijuana plantations in the wilderness contribute to the loss in numbers, but all the factors contributing to potential decline remain unclear. Meanwhile, the Karuk Tribe in Northern California is currently exploring ways to reintroduce porcupines onto their land.
Federal agencies have rolled out a four-rule regulatory package that would revise key definitions and processes governing habitat, species protections, habitat designations and federal consultations under the Endangered Species Act (ESA).
Newly proposed regulatory definitions for federal agencies implementing the ESA could make it easier for government projects to ignore indirect or uncertain negative wildlife impacts.
The proposals stem from the “Unleashing American Energy” executive order and recent Supreme Court decisions, which collectively directed agencies to reassess rules that could hinder domestic energy development or rely on agency Chevron deference. Chevron deference historically has allowed agencies latitude to interpret ambiguous statutory provisions and was overturned by the Supreme Court’s Loper Bright Enterprises versus Raimondo decision. If finalized, the changes to rulemaking would reshape implementation of the Endangered Species Act.
In Part 1, we outlined how two of the proposed rules would reinstate earlier ESA frameworks for listing, delisting, and critical habitat designations. In Part 2 we discussed the proposal to eliminate FWS’ long-standing “blanket rule” for threatened species. In an episode of the new podcast “Our Wild Lives”published on Friday, The Wildlife Society’ policy experts discuss these rule changes. This final installment dives into proposed changes to definitions that govern how federal agencies evaluate the impacts of their actions under ESA section 7 consultation.
Changing the definitions The U.S. Fish and Wildlife Service (USFWS) and the National Oceanic and Atmospheric Administration’s National Marine Fisheries Service (NMFS) propose reinstating the 2019 definitions of “effects of the action” and “environmental baseline,” two key terms used to determine whether federal projects may jeopardize listed species or adversely modify critical habitat.
“Effects of the action” refers to the impacts caused by a proposed action, including indirect effects reasonably certain to occur.
“Environmental baseline” describes the existing condition of a species and its habitat at the time consultation begins, including past and ongoing impacts not caused by the proposed action.
By reverting to the 2019 definitions and restoring associated guidance on causal analysis, the proposal emphasizes stricter standards for linking impacts to federal actions. The proposed rule highlights factors such as an agency’s legal authority over the effect and whether the impact would occur even in the absence of the project. This may limit the scope of impacts considered during consultation, especially for cumulative or multi-step effects.
Reweighing the benefits
The proposal would also remove the 2024 “offset” provisions, which allowed planned mitigation, like future habitat restoration, to be considered when evaluating project impacts. The agencies argue that such future actions are too uncertain and that the ESA does not authorize weighing speculative benefits against reasonably certain harm during consultation.
Together, these proposed changes would narrow the range of impacts analyzed during Section 7 consultation. If indirect or downstream effects are more difficult to attribute to federal action, agencies may be less likely to conclude that a project would jeopardize a listed species or adversely modify its critical habitat. These changes would not reopen past consultations—they would apply only to new or ongoing consultations initiated after the rule takes effect.
