PROTECT THE WILD—SILENT KILLING OF UNINTENDED CONSEQUENCES USING POISON

Forwarded this email? Subscribe here for more From hedgehogs to buzzards, Britain's wildlife is being quietly killed by rodenticide poisons Rodenticides aren't just a threat to rats and mice. Countless non-target animals are silently killed every year too. ELIZA EGRET AND TOM ANDERSON JUN 22 READ IN APP This is the second in a series of articles highlighting the need to ban rodenticides in the UK. Last week, we explored how UK councils are failing in their legal obligations to avoid causing unnecessary suffering. You can read the article here. In the coming weeks we will outline how poisons affect the water system too, and we will examine how humane alternatives can be used to control rodent populations. We will be making the case for local councils and private users to radically change their approaches to wildlife control in our communities. Rodenticides cause a slow, agonising death to rats and mice. But how many people know about the other silent victims of the poisons deployed by both local authorities and private users like farmers and gamekeepers? Companion animals, birds of prey, hedgehogs, foxes, badgers, bees and grey squirrels are being harmed or killed in the UK by Second Generation Anticoagulant Rodenticides (SGARs). We break down the available figures below. Countless other non-target animals suffer or die from consuming rodenticide without the ‘pest’ controllers, local authorities or the general public ever noticing. How does rodenticide harm non-target animals? There are two ways that non-target animals are killed by rodenticides: through primary poisoning, where an animal directly eats the bait, or through secondary poisoning, where an animal eats a creature which itself has eaten the bait. The suffering of a target species and the poisoning of non-target predators are not accidental outcomes. They are in the very design of SGARs. After eating a rodenticide bait, the animal may continue to consume more of the poison, unaware of its toxicity. The compounds accumulate in the body’s tissues, steadily preventing the capacity to clot blood, until the animal eventually dies from internal bleeding. This prolonged and agonising death is not an acceptable way to treat any animal, yet councils, pest-controllers, farmers and gamekeepers directly cause this suffering. The risk to predators through secondary poisoning is huge. For days after consuming the first bait, an animal remains alive, becoming more catchable as she becomes lethargic. A predator who then catches her ingests the same poison. Brodifacoum is one of the most potent and persistent SGARs available, and its use is growing as rodents develop resistance to other anticoagulants. Once ingested through secondary poisoning, it can remain in a predator’s body for more than 100 days. Every other poisoned animal consumed by the predator adds to the accumulating dose, meaning that the predator does not need to swallow a single large dose to be killed; the animal simply needs to keep eating. Ineffective attempt at regulation Secondary poisoning has been so prolific that in 2015 the Health and Safety Executive (HSE) forced the pest control industry and the Campaign for Responsible Rodenticide use (CRRU) to create new Code of Best Practice guidelines, as part of the Rodenticide Stewardship Scheme. However, a decade after its creation, the Rodenticide Stewardship Scheme has largely failed to deliver on its promise of meaningfully reducing wildlife exposure to SGAR residues. This failure can be clearly seen in the escalating number of non-target animals poisoned since the scheme’s inception. UK lagging behind in terms of legislation On a European level, rodenticides have been included on the European Union’s (EU) list of regulated biocidal products since the early 2000s. The EU regulations regarding the use of these products became more stringent with the introduction of the Biocidal Products Regulation (EU) No 528/2012 in 2013. The EU does allow the continued use of rodenticides, but only on a conditional basis. Namely, that rodenticides are used as a last resort. This has led both the Netherlands and Switzerland to ban the use of anticoagulant rodenticides for private users and adopt an Integrated Pest Management approach which prioritises preventative solutions and only uses rodenticides as a last resort. In the Netherlands, cholecalciferol-based rodenticides were banned too, and strict controls were placed on ‘pest’ control contractors. In the case of Switzerland, the legislative moves came after the publication of a Swiss study of deaths of non-target wildlife in 2022, which documented the effects on songbirds, foxes, birds of prey, hedgehogs, otters and fish. The report indicated “widespread contamination of the aquatic and terrestrial environment” by rodenticide poisons. Unsurprisingly, considering Brexit, the UK is lagging behind in terms of recognising the scale of the problem and protecting British wildlife. In 2024, in response to the alarming rise in the numbers of non-target wildlife killed, the use of SGARs in open areas such as fields was banned. However, rodenticides, including the highly-toxic brodifacoum, can still be used around buildings. The new regulations are likely to do little to protect non-target species falling victim to rodenticide poisoning. The animals killed Birds of Prey In November 2024, Wild Justice published a report titled Collateral Damage: The Rodenticide Stewardship Scheme – is it working?. The group used Freedom of Information requests to obtain laboratory test results submitted to the Health and Safety Executive’s Wildlife Incident Investigation Scheme (WIIS). The WIIS is a UK government monitoring programme that investigates the deaths of wildlife suspected to have been caused by pesticide poisoning. Wild Justice analysed the test results on the bodies of 366 buzzards and 173 red kites submitted in England between 2005 and 2022. Shockingly most of the buzzards and red kites WIIS analysed had traces of SGARS in their livers. Wild Justice also found that since the introduction of the Rodenticide Stewardship Scheme, the concentration of SGARs found in examined birds has been increasing, not decreasing. Wild Justice pointed out that - together with birds of prey being unintended victims of public ‘pest’ control schemes - SGARs were being used by farmers and gamekeepers to illegally kill them. This strengthens the case for a ban on the use of rodenticides as, if possession was illegal, it would be much more difficult to use them to illegally kill protected birds. Foxes A 2025 report published by the UK Centre for Ecology & Hydrology, titled SGARs in Mammals and Predatory Birds, also analysed data from the WIIS. The report shows that the red fox is one of the most heavily contaminated mammals of all the species studied, with a mean liver SGAR concentration of 993 ng/g. This is far higher than any of the predatory birds and roughly five times higher than the badger. Of the 127 foxes tested between 2006 and 2021, contamination levels increased significantly over the monitoring period. The proportion of foxes with detectable SGAR residues rose sharply from 75% before 2015 to 93% after the regulatory change, meaning that since 2016, 93% of the foxes tested have been found to carry rodenticide in their livers. Notably, this includes a significant rise in bromadiolone and brodifacoum. These findings show that neither the regulatory framework nor the CRRU’s industry-led stewardship regime has succeeded in protecting foxes from increasing contamination. Foxes are scavengers, and the urban habitats they live in are likely to provide greater opportunity to encounter SGAR-contaminated rodents or their carcasses, potentially combined with a higher prevalence of rodenticide-resistant rats that require repeated or stronger treatment. Hedgehogs Despite being a beloved and increasingly threatened species, the hedgehog fares poorly in the UK Centre for Ecology & Hydrology report’s analysis, although the data is limited. Of the 11 hedgehogs tested by WIIS between 2007 and 2021, 55% were found to carry detectable SGAR residues in their livers, with a mean concentration of 12.5 ng/g. The sample size is extremely small and the findings should be treated with caution. Nevertheless, the fact that over half of the hedgehogs tested showed detectable contamination is concerning, particularly given that hedgehogs are already under severe pressure from habitat loss, road deaths and declining invertebrate populations. It is also telling that the WIIS data for hedgehogs is so sparse, and likely reflects how rarely poisoned hedgehogs are found and submitted for testing rather than any genuine rarity of exposure. Badgers Of the 55 badgers tested by WIIS in England and Wales between 2006 and 2021, just over half (56%) showed detectable SGAR residues before 2015, rising to 71% after the regulation change. More striking is the picture for brodifacoum specifically: detectable residues were found in just 18% of badgers before 2015, rising sharply to 62% afterwards, a statistically significant increase. Mean liver SGAR concentration across the whole period was 186 ng/g, though some individuals showed extremely high concentrations, with a maximum of 2,843 ng/g recorded. The significant upward trend in brodifacoum residues is consistent with the pattern seen across most other species in the report, pointing again to brodifacoum as the compound of greatest and growing concern. Grey squirrels The grey squirrel data in the UK Centre for Ecology & Hydrology report is striking but must be treated with considerable caution given the very small sample size. Of the 16 grey squirrel cadavers tested by the WIIS in England and Wales between 2006 and 2021, 56% showed SGAR residues below the limit of quantification, suggesting low or no detectable exposure. However, four individuals (25% of the sample) showed extremely high liver SGAR concentrations ranging between 811 and 6,500 ng/g, pulling the mean up to 1,175 ng/g - the highest mean of any species in the study. What the grey squirrel figures illustrate most clearly is not a reliable picture of population-level exposure, but the potential for catastrophic individual-level poisoning when a squirrel does encounter rodenticide-contaminated food. Companion animals Annual reports from the Veterinary Poisons Information Service (VPIS) provide a detailed picture of animal poisoning cases in the UK, and show how companion animals are affected by SGARs. The 2025 report draws on data from 32,000 cases during the year. Anticoagulant rodenticides were the third most common agent across all species in 2025, accounting for 2.9% of all agents recorded, behind only chocolate and non-steroidal anti-inflammatory drugs (NSAIDs). This ranking is described by the report as unchanged from previous years, indicating that SGAR poisoning is a persistent and recurring concern in UK veterinary practice. In dogs specifically, anticoagulant rodenticides were again the third most common enquiry, making up 5.9% of all dog-related agent enquiries. The most frequently recorded individual compounds in dogs were brodifacoum (559 cases), difenacoum (424 cases) and bromadiolone (278 cases). Data from the WIIS, analysed by Protect the Wild, also documents several reported cases of poisoning of dogs with rodenticides. These incidents are directly linked to local authority and contractors laying poisons. SGARs also appeared in enquiries relating to rabbits (4.7% of rabbit cases), birds (17.9% of bird cases) horses and donkeys (19.4% of equine cases), indicating that exposure is not limited to domestic pets but extends across a wide range of animals. Next week, Protect the Wild will take a look at the effect of SGARs on our seas and rivers as well as on fish, otters and seabirds. Our demand: An immediate end to rodenticide use Protect the Wild is demanding a complete and immediate ban on the use of rodenticide baits. Rodenticides are killing non-target wildlife: Poison bait placed outside does not and cannot discriminate between target and non-target species. Killing protected wildlife is a crime. Rodenticides are causing unnecessary suffering: The slow, agonising death inflicted by SGARs – which cause internal bleeding over many days – may itself constitute an offence under the Animal Welfare Act 2006, which prohibits the causing of unnecessary suffering to animals. We are already obliged to do better: Existing legislation, as well as the pest control industry’s guidelines, require that preventative methods such as rodent proofing and prevention measures are exhausted before any rodenticide is used. The routine use of poison bait as a first resort is likely unlawful. Humane solutions are not complicated and there are companies out there who follow an ethical approach to managing wildlife in public areas. Check out Humane Wildlife Solutions, for example. As animal rights advocates, we urgently need to step up efforts to stop the silent killing of our wildlife by SGARs and other poisons. We need to make our case loudly and set out the alternatives clearly. The routine use of lethal poisons causes immeasurable suffering and it needs to stop. SHARE LIKE COMMENT RESTACK © 2026 Protect the Wild Protect the Wild, 71-75 Shelton Street Covent Garden, London, W2CH 9JQ Unsubscribe Start writing