On November 24, 2025, two landmark reports—one from California and another from Wales—have sounded urgent alarms about the accelerating threats to wildlife, revealing that species on both sides of the Atlantic are facing unprecedented risks from human activity and environmental neglect. The findings, released by the California Department of Fish and Wildlife and Natural Resources Wales, paint a vivid picture of widespread harm: from the hidden dangers of rat poisons infiltrating food webs in the American West, to the quiet crisis of extinction looming over thousands of species in the UK.
According to the California Department of Fish and Wildlife's 2024 statewide survey, blood-thinning rat poisons—known as anticoagulant rodenticides—were found in the bodies of 95% of mountain lions and 69% of nontarget wildlife tested across the state. As reported by the Center for Biological Diversity, these powerful chemicals have left a trail of unintentional poisonings among dozens of wildlife species, including mountain lions, hawks, owls, bears, bobcats, and even river otters. The report’s findings come despite years of legislative efforts to restrict the most toxic rodenticides, with Governor Gavin Newsom and state lawmakers enacting measures aimed at protecting vulnerable species.
Yet, in a twist that has conservationists on edge, the California Department of Pesticide Regulation has proposed rolling back these restrictions. If enacted, the proposal would allow the use of the most toxic rat poisons at more than 100,000 new locations—grocery stores, restaurants, highways, roads, parks, and even wildlife areas. This move has spurred a wave of concern from environmental advocates and lawmakers alike. In a letter signed by six California legislators, they warned that expanding the use of rodenticides would "lead to more wildlife poisonings" and described proposed safer rodent-control methods as "flimsy and unclear."
Lisa Owens-Viani, director of Raptors Are The Solution, expressed her frustration, telling the Center for Biological Diversity, "It is dismaying to see the continued impact of anticoagulant rat poisons on great-horned owls and red-shouldered hawks, some of our best natural rodent-controllers. Now is hardly the time to relax restrictions when, in fact, our state Department of Pesticide Regulation should close the loopholes in the law to truly protect these animals."
The scale of the problem is staggering. State regulators have documented unintended poisonings in at least 38 different species in California alone, including the famous Hollywood mountain lion P-22, the imperiled San Joaquin kit fox, northern spotted owls, and bald eagles—83% of which tested positive for rodenticides. Even aquatic ecosystems are not spared, with river otters showing contamination, indicating that these poisons are making their way into waterways.
Assemblymember Damon Connolly (D-San Rafael) underscored the urgency, stating, "The evidence that wildlife is continuing to be exposed to these harmful chemicals at alarming rates is further reason that the California Department of Pesticide Regulation should promulgate robust regulations to reduce their use. The California legislature has worked for well over a decade to enact laws to protect wildlife, children and pets from these dangerous pesticides. Now it is up to the California Department of Pesticide Regulation to uphold their mission of ‘protecting human health and the environment’ by reducing the use of, and exposure to, anticoagulant rodenticides across the state."
The problem is not unique to California. Under the Biden administration, the Environmental Protection Agency has found that rodenticides are pushing at least 78 endangered species—including California condors, Florida panthers, and black-footed ferrets—toward extinction. The evidence is clear: the ripple effects of these poisons are far-reaching, threatening the delicate balance of entire ecosystems.
There is, however, a glimmer of hope in the form of alternative pest management. According to SafeRodentControl.org, effective strategies include sealing entry points to buildings, improving sanitation, fertility control, and deploying a variety of traps. These methods offer a path forward that doesn’t rely on chemicals that linger in the environment and accumulate up the food chain.
Across the Atlantic, a different but equally urgent crisis is unfolding. Natural Resources Wales (NRW) has released a "first of its kind" report identifying thousands of species at risk of extinction in Wales. The study found that 3,000 species now exist in five places or fewer, making them acutely vulnerable to habitat loss, climate change, and sudden catastrophic incidents like storms. Since the start of the millennium, Wales has already lost 11 species, including the European turtle dove and belted beauty moth, which have become geographically extinct in the country.
The Species in Peril report highlights a roster of at-risk species, including the high brown fritillary butterfly, the rainbow-coloured Snowdon leaf beetle, the Arctic-Alpine pea mussel, woolly feather-moss, and eyed chestnut wrinkle-lichen. Mannon Lewis, strategic projects lead for NRW, emphasized that saving these species may not require massive investments. "Some of the solutions for these species are incredibly simple. It is to do with changing the grazing regime, changing when we cut our grass, not felling, looking at different ways of trimming our hedges. They are low-cost, simple measures and now we know exactly where we need to do it," she explained to BBC News.
Targeted conservation efforts are already bearing fruit. At Newborough Warren on Anglesey—a national nature reserve home to 130 at-risk species—projects such as introducing ponies to graze and opening up dunes to the elements have led to the return of beetle species not seen there in a decade. Mike Howe, one of the ecologists behind the study, noted, "Within months of opening up some of these bare areas, we had species of beetle, which hadn't been recorded on Newborough for about 10 years, suddenly appearing in huge numbers."
The report also underscores the importance of nature reserves and Sites of Special Scientific Interest (SSSI) in safeguarding biodiversity. Conservationist Tyler Hallman pointed out that NRW’s approach—linking networks of special sites—could even pave the way for species currently extinct in Wales to make a comeback. "The European turtle dove is extinct in Wales but, over the last few years, their population in Europe has increased greatly so who knows—that one might come back. You might see things coming back as conditions improve and the species as a whole do better. I guess that's a huge positive—there are things we can do," Hallman told BBC News.
Both reports converge on a central theme: that while the threats to wildlife are grave and mounting, there are tangible steps that can be taken to reverse the tide. Whether it’s closing regulatory loopholes in California or tweaking land management practices in Wales, the future of countless species hinges on choices made today. The stakes, as these new findings make clear, could not be higher.
