Something Wild is all about appreciating nature, whether it’s in your backyard or on a mountain trail. While we may not love rodents like mice and rats, they have a role to play in the ecosystem.
Efforts to control rodents like rats and mice by poisoning them means we are also poisoning the animals that prey on them: red-tailed hawks, eagles, or any of the predators in the food chain like foxes, raccoons, fishers, or coyotes. It’s called “secondary rodenticide poisoning.”
You may recall Flaco, the Eurasian Eagle-Owl that escaped the zoo and charmed millions of people in Central Park in 2023. He was found to have four different types of what’s called second generation anti-coagulant rodenticides – or SGARS – in his system.
These poisons were developed in the 1970s when rodents became resistant to the older, “first-generation” poisons. Second-generation poisons kill faster and remain in animal tissues longer, meaning raptors and other animals are at risk.
Part of the issue is that rodenticides create an “out of sight, out of mind” effect. The rodents disappear and we don’t see what comes next.
These poisons prevent blood from clotting. So animals don’t just die, they bleed internally. It can take days. And when a rodent eats the bait it becomes slow and disoriented, making it easy prey for a hawk, owl, fox, or coyote. Thus the poison moves up the food chain.
Wildlife rehabilitators describe horrible deaths: hemorrhaging and seizures are just two of the painful ways they die, as the poisons that kill the rodents act in the same way to the predators.
While Flaco made headlines, this is happening quietly here in New Hampshire and across the U.S. Wildlife rehabilitators are seeing more hawks and owls, as well as fishers, raccoons and bobcats, with signs of rodenticides in their systems.
And there’s no way to precisely track how many predators have been killed by SGARs in the wild.
Federal law bans the retail sale of SGARs, but these poisons remain legal for use by licensed pest control professionals. The poison bait stations are plentiful: outside grocery stores, restaurants and housing complexes. You may have seen little plastic boxes next to a building or dumpster; they’re also disguised as plastic rocks.
Organizations like NH Audubon have supported efforts to restrict these products. Even with some regulations in place, they are still widely available. This means that the choices people make at home have real effects beyond what we see.
Are glue traps any better?
Glue traps are just a different kind of problem. They are indiscriminate; anything that gets stuck can die there, including many songbirds.
Steps you can take
The first step is prevention: seal up entry points like small holes in foundations, store food and trash properly, and reduce what is attracting rodents in the first place.
Second, if control is needed use more targeted methods like a snap trap. They aren’t pleasant but they are far less likely to impact wildlife or your pets.
And third, avoid rodenticides whenever possible. If you have a big pest issue, talk to a pest control professional about how to control rodents. Ask them what products they use and how to avoid using rodenticides.
It’s something people can be more aware of, whether at home or even noticing and talking to businesses with those bait boxes.
There have been species brought back from extirpation, like beavers or turkeys, and success stories of birds struggling with the effects of pesticides. Ospreys, bald eagles, peregrine falcons, and loons have all been brought back from the brink of disappearing from N.H. and nationwide by the enlightened regulation of insecticides like DDT.
Part of the challenge may be that “raptors” or “predators” can feel a little abstract. But if you picture a barred owl in your backyard, the one calling “who cooks for you?” at night, realize that that bird is at risk from a poison it never even touched.
Something Wild is a collaboration between the Forest Society, NH Audubon and NHPR.
