PROVIDENCE — What happens when a link in the circle of life is human-made?

Rats are a species of animal close to the bottom of the ecosystem’s food chain. Their smaller size makes them a great meal for bigger, faster predators such as hawks, owls, and other raptors, and their habit of living amid human development to scrounge for food makes them an unwanted neighbor.

They’re a boon for pest control companies, who use a class of lethal pesticides known as second-generation anticoagulant rodenticides (SGARs for short) in black box bait stations in buildings known to harbor rat infestations.

But those poisons aren’t just lethal for rats; they’re also poisonous for the wildlife that eat rats. Sheida Soleimani, the founder and executive director of Congress of the Birds, the state’s only bird-specific wildlife rehabilitator, told lawmakers she sees birds in her care die daily because they had rodenticides in their system.

Soleimani noted earlier this year that Providence animal control officers brought her a bald eagle, found in Roger Williams Park near the black bait boxes used to trap and kill rodents. The eagle, she said, later died in her arms.

“I suspected that it was anticoagulant rodenticide,” she said. “After necropsy it tested extremely high for second-generation anticoagulant poisons in its blood.”

Congress of the Birds admitted 148 birds of prey into its care last year, Soleimani said, and all of them tested positive for anticoagulants in their blood. A total of 86 birds died or had to be euthanized because of it, she added.

“How many more birds suffer before we take action?” Soleimani asked lawmakers. “How many more hundreds will die in my arms? Rodenticides are not an unnecessary evil, they are an unnecessary cruelty.”

SGARs were first developed in the 1970s, in response to rodents becoming resistant to the first generation of rodenticides. They’re known for killing rats and mice after only a single night of feed, but they pose a long-term problem to other wildlife because they stay in animal tissue far longer than the first generation of rodenticides. SGARs work by interfering with blood clotting, causing death from excessive bleeding.

The Environmental Protection Agency has banned the sale of such rodenticides in stores, and they are only accessible through commercial pest control companies.

The House Municipal Government and Housing Committee, before which Soleimani testified on March 11, is considering a bill (H5704), introduced by Rep. Rebecca Kislask, D-Providence, that would restrict the sale of SGARs in local stores and online and ban their use by state and municipal governments, medical waste facilities, warehouses, and agricultural sites. The bill also directs municipalities to participate in a voluntary pilot program to use rodent contraceptives to curb their expanding populations.

Similar legislation (S0651) was sponsored in the Senate by Sen. Melissa Murray, D-Woonsocket, and received its committee hearing March 19. Both bills are heavily supported by environmental groups such as the Audubon Society of Rhode Island, which has made the legislation one of its marquee bills this year, Clean Water Action Rhode Island, and Save The Bay.

Phoenix Wheeler, director of advocacy for the Audubon Society, said the benefits of rat poisons don’t outweigh the long-lasting risks and impacts to wildlife and the environment. Wheeler told committee members of the Senate Environment and Agriculture Committee they prefer rodent contraceptives to control rat populations, arguing it is more humane.

“Rat poisons take five to 10 days to kill rats one by one, increase the risk for rodent diseases, increase ER and poison control center visits for children, saturate poisons up and down the food chain and waterways,” Wheeler said. “Contraceptives, while slightly more expensive, will prevent up to 15,000 rats a year from being born and come with much less risk to anyone.”

Pest control businesses, including representatives from the Big Blue Bug Solutions Pest Control and New England Pest Management Association, largely oppose the bans on rodenticides, preferring an integrated approach, and asked lawmakers to oppose the legislation.

“Rats are among the most successful mammals on earth, next to humans,” said Nathan Jewett, an associate certified entomologist for Big Blue Bug Solutions and a member of the New England Pest Management Association. “Their ability to adapt in diverse environments is unparalleled. It’s for that reason we prefer to use every tool available in the toolbox to combat these pests in our homes and communities.”

Rats have become a hot political issue in Rhode Island over the past few years. ecoRI News reported on the increased spread of rats in municipalities like Cranston. The city, which employs the state’s only municipal rat czar, runs a free baiting program for residents, and requests for traps exploded during the pandemic.

H5704 and S651 were both held for further study.

Corrections: Due to a reporting error, an earlier version of this story misquoted Phoenix Wheeler as saying rat poisons take 10 to 15 days to kill rats one by one. Wheeler testified the poisons kill rats in five to 10 days. This story has been updated.

The photo with this story initially misidentified the bird as a red-tailed hawk. It is a northern harrier.