by Joe Eaton
(Full article from RATS Tales January 2026)
To most Americans, the word “scheme” probably suggests something nefarious; we’d think of the Grinch, or maybe Iago in Othello. In British English, though, there’s another common meaning. A scheme can be just a plan, often an official one, for anything from growing peanuts in East Africa to the British “Rodenticide Stewardship Scheme” (RSS), which allegedly monitors the expanded use of second-generation anticoagulant rodenticides (SGARs).
In return for allowing the SGARs brodifacoum, flocoumafen, and difethialone to be used outside buildings (including in sewers), the RSS gave the pesticide industry responsibility (including cost) for tracking SGAR residues in the western barn-owl, a sentinel raptor species. Resulting data would be used to reevaluate the RSS after five years.
According to Ed Blane, whose Wildlife Poisoning Research UK group (WPRUK—click Reports for raptor and fox reports) has analyzed government data, the Scheme has been an abject failure. For one thing, the RSS neglected SGAR impacts on diurnal raptors such as peregrine falcons, common buzzards, and red kites, and on the red fox, a predator/scavenger. WPRUK’s reports show an alarming surge in SGAR contamination in all of these species, and the poisoning of red kites threatens to reverse decades of conservation efforts. Blane also says both Conservative and Labour governments have failed to release recent monitoring data and have reneged on promises to review the Scheme.
The RSS originated with the Campaign for Responsible Rodenticide Use (CRRU), an “astroturf” group funded by the pesticide industry, when David Cameron led a Conservative Party government before the Brexit referendum. The impetus was a government assessment in 2012 that SGARs posed unacceptable environmental risk. Major players in the Scheme’s development included chemical industry giants like BASF, Syngenta, and Bell Laboratories; professional pest control associations; farmers’ unions; and gamekeeper groups. For anyone who missed Lady Chatterley’s Lover, gamekeepers police the hunting estates of the British landed gentry against raptors and carnivorous mammals that might get to the game birds first. Blane says gamekeepers often resort to the intentional poisoning of predators. The Royal Society for the Protection of Birds (RSPB) and the nonprofit Barn Owl Conservation Network were also on board.
In return for outdoor use of the three SGARs, the CRRU and its allies agreed to take action to reduce SGAR exposure in wildlife by educating users in best practices and controlling the rodenticide supply chain. Britain’s Health and Safety Executive, responsible for approving rodenticide use in the UK, rubber-stamped the CRRU’s proposals, which took effect in April 2016. A Government Oversight Group (GOG) was tasked with issuing annual reports on the progress of the RSS, followed by a review after five years.
That five-year review never happened. There have been no annual reports since 2020, and, according to WPRUK founder Ed Blane, the government has tried to suppress barn owl monitoring data.
Blane says a new GOG paper with recommendations for strengthening stewardship was set to be discussed with CRRU in December 2025, but the meeting was cancelled and no new date has been announced: “It appears that yet again the [government] and the chemical industry are kicking the can down the lane.”
Blane, a former Ministry of Agriculture pest control advisor who also investigated wildlife poisoning incidents for the government’s Wildlife Incident Investigation Scheme (WIIS), was awarded a Lifetime Achievement Award by the World Wildlife Fund the year before his retirement in 2023. Frustrated by the lack of transparency on the part of industry and government, he launched WPRUK to get a clearer picture of SGAR exposure in diurnal raptors and mammalian carnivores using WIIS data.
The results, issued in a series of reports in 2025, were alarming. For the common buzzard, a Eurasian relative of the red-tailed hawk whose British population has declined since 2020, brodifacoum exposure in particular spiked from 2020 to 2023. A quarter of all the buzzards tested in England and Wales between 2021 and 2023 had brodifacoum liver concentrations exceeding 0.2 milligrams per kilogram, a potentially lethal level. Bromadiolone and difenacoum exposure also increased during that period, but by much lower amounts. Exposure to all SGARs in British peregrine falcons jumped from 46.2 percent in 2005-2015 to 75.5 percent in 2016-2023, with brodifacoum and bromadiolone accounting for most of the increase. Two falcons had total SGAR concentrations of around 0.09 milligrams per kilogram.
For the red kite, WPRUK compared WIIS data from Wales for two periods, 2005-2013 and 2019-2023. Between those periods, the proportion of kites with potentially lethal levels of SGARs in liver tissue rose from 48.3 to 62.9 percent, and the amount of SGAR residue at high exposure levels rose by 102.9 percent. The average level of brodifacoum in the liver samples went up by 355 percent.
There’s a painful irony here. The versatile red kite preys on small mammals and birds, but it’s mostly a carrion-feeder. For its sanitation services, it was given protected status in sixteenth-century England and Wales. But it became a rare species in Britain, more readily found on Yorkshire Gold Tea packages than in the wild. A residual population hung on in Wales, down to five breeding pairs by the 1950s. The kite became a Welsh national symbol, and some residents began putting out livestock carcasses for the birds. After the Welsh population rebounded, kites from Wales, Sweden, Germany, and Spain were translocated to England and Scotland.
By 2010, the UK had at least 2200 breeding pairs. SGAR poisoning now threatens to undo that hard-won recovery.
It’s not just raptors. In a fourth report, WPRUK documented higher average exposure levels in English and Welsh red foxes after the RSS took effect. The proportion of foxes with levels exceeding 0.2 milligrams per kilogram increased from 32.3 percent to 51.9 percent.
WPRUK’s findings on buzzard exposure reinforced a 2024 report from Wild Justice, one of the few nongovernment organizations engaged with the rodenticide issue. Wild Justice used 2005-2022 WIIS data for England, which showed an increase in liver residues since 2016, primarily driven by brodifacoum. Their red kite data indicated high exposure before and after the regulatory change. The report’s conclusions characterized the RSS “a failed scheme” and called for an end to outdoor use of brodifacoum, more funding for research, and more stringent enforcement. Wild Justice’s conclusion: “The current situation is a pathetically poor response by government agencies to a threat to wildlife and potentially to people and livestock.” The RSPB, which was involved in the development of the RSS, doesn’t address rodenticides on its website and didn’t respond to a request for comments.
What about the barn owl, the designated sentinel species? Blane considers it a poor choice. “Using the barn owl as the only monitoring species was a very BAD decision as it would only look at one route of exposure—that of small mammals—mice and voles, taking SGAR bait and then being predated by barn owls,” he said in an email. “This ignores the exposure route of bigger predators / scavengers taking dead / dying rat.”
An April 2025 report from the government agency Natural England showed significant increases in brodifacoum and bromadiolone in barn owl livers after 2016, based on WIIS data from England and Wales and data from other sources. Common buzzards, Eurasian sparrowhawks (comparable to the American sharp-shinned hawk), peregrine falcons, red foxes, and Eurasian badgers showed a similar pattern. Red kite results, using data from the Predatory Birds Monitoring Scheme covering all regions of Britain, were comparable to those in the Wild Justice report, with similarly high exposure for the two time periods. Unsurprisingly for a government agency, Natural England punted on the regulations, only recommending further research into ecological factors driving SGAR exposure.
Although there’s no question about the trends, Blane says the political will to address them has been lacking. Despite the inaction of both Conservative and Labour national governments, it’s possible in theory that something could be done at the regional (England, Wales, Scotland, Northern Ireland) level, since the SGAR regulations are a “devolved matter,”allowing for different rules in different regions. However, he adds that the current Welsh Labour government “is currently just following whatever the UK government tells them to do.” If Labour loses its majority in the Senedd (the Welsh Parliament) in May’s general election, a Plaid Cymru (Welsh nationalist) government may be open to restricting the use of SGARs.
Whatever happens in the UK, the consequences of relaxing SGAR restrictions offer a powerful object lesson for the rest of us.
Because of the efforts of a strong environmental coalition, California has made significant progress in restricting the use of ARs although exemptions have prevented full success. Now the California Department of Pesticide Regulation wants to turn the clock back, creating loopholes for expanded AR use in commercial settings and open space, including wildlife habitat. The coalition—and California’s wildlife—need all the help they can get in ensuring that the Golden State doesn’t repeat the British experience. (Click here to add your voice and help us keep moving forward, not backwards!)
