Written by Emily Beckett of the Humane Society of Vancouver for The Daily Hive
Earlier this year, British Columbia wildlife advocates cautiously celebrated the news of a partial ban on second-generation anticoagulant rodenticides. Anticoagulant rodenticides cause a slow and painful death through internal bleeding in animals that ingest them. The British Columbia government has noted the grave risks these highly toxic toxins pose to the public, pets and wildlife, and has specifically banned – with several exemptions – the types of poisons most effective for rats and wildlife alike.
With reports of mortalities and wildlife dying from suspected rodenticide poisoning making headlines in recent years, the issue has gained much-needed attention and calls for a ban on rodenticides have grown.
While the government’s announcement was a welcome first step, it is becoming increasingly clear that much more needs to be done to effectively address the widespread use of all inhuman and indiscriminate toxins, both first and second generations. The ban itself is incomplete, leaving a wide range of exceptions where second-generation poisons can still be used. It also ignores other harsh and dangerous rodenticides, such as first generation and non-anticoagulants.
First-generation rodenticides are so called because they have been used for many years and begin to lose their effectiveness on rodents, while their effect is still negative if another animal eats a poisoned rat or mouse. This is called secondary poisoning. For example, two common first-generation anticoagulants, difacinone and chlorofacinone, pose a significant risk of secondary toxicity to wild mammals, cats, and dogs. Veterinarians have also raised concerns about promethalin, a neurotoxin that does not have a specific antidote, yet its use as a rodenticide is still permitted.
At the time the partial ban was enacted, the county indicated that pest control operators would be informed of the new rules to ensure compliance. However, months later, the public continues to find bait boxes labeled as containing second-generation rodenticides in places where their use is prohibited, such as outside apartment buildings and offices.
Concern about the apparent lack of enforcement and compliance surrounding the ban turned to frustration when a large horned owl was found dead earlier this month near the Environment Department building in Victoria. A closer look around the exterior of the building by a local wildlife advocate led to the discovery of rodent bait boxes with labels indicating they contained the toxin bromadiolone – a second-generation poison in a setting that appears to be in violation of the ban. While the ministry has since responded, saying that the investigation concluded that the labels on the bait cans were incorrect and that they did not contain bromadiolone, the incident illustrates the issues surrounding the partial ban. How can the public ensure that bait boxes they encounter in their community are accurately labeled and compliant with partial bans?
Meanwhile, owls and other birds of prey that commonly fall victim to rodenticides continue to appear in rehabilitation centers, raising concern that partial bans may not lead to intended changes to the animals. The number of owls that have died since the ban has not changed, the British Columbia-based Orphan Wildlife Rehabilitation Association said. A few years ago, a blood-testing study found that more than half of the animals in OWL care had residual toxins in their system.
To effectively address and reduce rodenticide use, the county government should proactively impose its current partial ban on second-generation rodenticides. In addition, as the government is currently considering next steps in relation to this issue, it is critical that the long list of exemptions be reconsidered and that the government eventually phase out all types of rodenticides, in favor of humanitarian alternatives and preventive measures that address the root causes of the conflict. between humans and rodents.
Treating attractants, such as open litter, compost bins, fallen fruit or bird seed, and repairing structural defects and access points in buildings that provide food sources and shelter for rodents, is fundamental to resolving conflicts between humans and rodents. Meanwhile, a variety of toxin-free alternatives to lethal administration are available and new and innovative techniques are being tested and piloted in communities. Alternatives range from snap traps to tethered traps, rodent deterrents and owl boxes that support the presence of natural predators – a family of owls can consume more than 1,000 rodents per year!
With growing awareness about the threats rodenticides pose and the suffering they cause, we can and must do better.