When “MK” was found on the ground in Arlington’s Mount Pleasant Cemetery last winter, the bald eagle was severely anemic, lethargic and struggled to stand.
The emblem bird of prey died less than two days later after spontaneously hemorrhaging, rat poison the suspected killer. She was the fourth bald eagle in Massachusetts since 2021 whose death has been connected to rodenticides, the spectrum of chemical pesticides that kill rodents.
What MK’s death spotlighted for many is the grisly byproduct of these pesticides, that they can also kill the animals that eat rodents. Her story has furthered an effort to end the use of second-generation anticoagulant rodenticides (SGARs) in Massachusetts, the most potent kinds of rat poison that prevent blood clotting.
“She’s the animal that is pushing this paradigm,” said Rachel Mathews, an animal rights attorney.
Meanwhile, pest management professionals contend rodenticides are one tool of many they can deploy depending on a situation — and an important one, at that.
Future anticipated action from the U.S. Environmental Protection Agency on SGARs could also dictate what direction the Commonwealth takes.
Rodenticides have been used for decades as a tool to manage rodent-related diseases and damage, from urban cities to farmland. They’re most commonly seen in the form of black bait boxes.
The chemicals move through the food web, ultimately impacting predators such as owls, hawks, eagles, foxes, coyotes, fishers and bobcats. For this, wildlife advocates have been doggedly ringing the alarm.
There have been inconclusive but persistent legislative efforts on Beacon Hill to lessen the use of SGARs. At the community-level, local action has been taken in towns such as Arlington, Lexington and Newbury — bans on municipally-owned properties, town meeting resolutions and home rule petitions.
When MK died, hundreds of people rallied at Arlington Town Hall to mourn her and push lawmakers to further restrict SGARS. Just months earlier, in January 2023, Arlington had taken its own steps to ban SGARs on all town-owned properties as a result of prior citizen activism.
Now, the Harvard Law School Animal Law and Policy Clinic is working to gain ground with the agency that oversees rodenticides in the state.
Representing a handful of wildlife rehabilitators, the clinic is petitioning the Department of Agricultural Resources, arguing its annual registrations of anticoagulant rodenticides go against the state’s own Pesticide Control Act, which allows for pesticides that “will not cause unreasonable adverse effects on the environment.”
What are the rules around these rat poisons?
Rodenticides are regulated at both the federal and state levels. Per EPA restrictions, SGARs, the more potent of rodenticides, can’t be sold for individual consumer use, but licensed pest professionals and agricultural users are permitted to use them and do.
The EPA cut off retail sales of SGARS in 2015, but they can still be purchased online in commercial use quantities.
In Massachusetts, in order to sell or use a rodenticide, manufacturers have to apply to register their product with the five-member Pesticide Board Subcommittee of the state’s Department of Agricultural Resources.
Registrations expire on June 30 of each year and must be renewed, meaning the state reviews its allowable rodenticides annually. All rodenticides in Massachusetts, including SGARs, are classified as “general use” versus “restricted use,” the latter of which requires advanced licensing.
A harmful poison or ‘vital’ tool
The petition from the Animal Law and Policy Clinic — which includes photos of a hawk bleeding from its beak and an emaciated young fox — requests that the Department of Agricultural Resources immediately suspend all registrations of anticoagulant rodenticide products and conduct an individual review of their active ingredients before determining future eligibility.
“What our petition argues is that poisoning raptors and coyotes and foxes and all of those animals who eat rodents, we believe that that is an unreasonable, adverse effect on the environment,” said Mathews, a former clinical instructor at the Animal Law and Policy Clinic who helped write the petition.
In a statement in response to the petition, a spokesperson for the Department of Agricultural Resources said they’re currently reviewing the request while keeping an eye on expected action by the EPA.
In 2022, the EPA issued a proposed interim decision that would put in place new rodenticide restrictions. The proposal, which applies to 11 total types of rodenticides, would classify all SGARs as restricted use pesticides.
“EPA is currently still in its review phase of the (proposed interim decision) and MDAR awaits the agency’s final decision,” the state agency’s spokesperson said.
MDAR would not comment on what the suspension of registrations, as requested in the petition, would mean in practice.
David Flynn, president of the New England Pest Management Association and operations manager at Burgess Pest Management in West Bridgewater, described rodenticides as “one tool in the toolbox” of techniques, a “vital” one to employ when needed.
“Our industry, we’ve spent a lot of our training focusing on all sorts of other tools, whether it be site sanitation, exclusion tactics, old-school trapping,” Flynn said. “There’s also newer products that focus on CO2 and treating burrows with dry ice. All of those can be effective, but you also need to be able to have rodenticide. There has to be some use of rodenticide.”
He cited an urban apartment building as an example where rodenticides may be the desired method of control. While traps are “great,” he said, most only catch one rodent and they have to be checked daily, making them an “uneconomical” and inconvenient option in that particular scenario.
Flynn argued a bait box could last for over a month before a pest control service has to service it again.
If SGARs in Massachusetts were reclassified as “restricted use,” businesses or individuals using them would need a certified pesticide license, which isn’t required for those applying general use pesticides.
Flynn’s industry has been closely tracking possible changes coming down the pipeline. In fact, they’ve come to expect them.
“We’re not standing on the side saying, ‘We need rodenticides because that’s all we’re going to apply,’” Flynn said. “It’s one tool. We are, as an association and my business, we are teaching and training other tactics for rodent control.”
‘These beautiful animals bleeding out’
After they all bled to death, Erin Hutchings lined up the family of deceased great horned owls for photographic proof.
The mother had been discovered dead at the base of a tree, and one of her owlets was dead in the nest overhead. A second later perished at a nearby wildlife rehabilitation center.
A necropsy of the trio later performed at Kansas State University confirmed widespread hemorrhaging caused by anticoagulant rodenticide toxicity — death by rat poison.
These reoccurring stories are mostly the same, just different cities and towns. This time was in Framingham in April.
“I’m sick of seeing it, these beautiful animals bleeding out and there’s nothing I can do about it at end stage,” said Hutchings, a rehabilitator at Gloucester-based Cape Ann Wildlife. “And treatment is exhausting. It’s physically and emotionally taxing, these animals I volunteer my life for.”
In 2020, Tufts Wildlife Clinic tested a sample of more than 40 Massachusetts red-tailed hawks, finding that 100% of them were positive for anticoagulant rodenticides with SGARS identified most commonly.
By analyzing Department of Agricultural Resources data, Mathews said they found that Massachusetts commercial applicators used over half a million pounds of anticoagulant rodenticides in 2022 alone, and 96% were SGARs.
As of March 26 of this year, the Pesticide Board Subcommittee had registered 71 pesticide products containing SGARs for use in Massachusetts.
When Hutchings, a veterinary tech, started in volunteer animal rehabilitation, most bird injuries and deaths she saw were due to vehicle strikes. Rodenticides have since surpassed those, she believes.
“You’re taking away those natural predators that we need around here to control the rodent population,” Hutchings said. “It’s screwing up the whole system.”
Rats are a growing national conversation
The petition to suspend certain rat poison registrations in the state comes amid heightened national conversation about the long-tailed rodents and how they’re impacting quality of life for people who reside in cities, as well as health and sanitary conditions.
The Boston City Council recently floated the idea, and not for the first time, of a new pest control office, as rat populations appear to be on the rise in major cities. Between 2020 and 2022, the number of rat-related complaints by Boston residents rose by 86%.
This fall, New York City, which last year appointed its first “rat czar,” will host the first National Urban Rat Summit, Mayor Eric Adams’ administration recently announced.
Mathews, the animal rights attorney, argued the visual presence of rats in cities is partly attributable to society’s dependance on rodenticides.
“I want to address this idea that there’s a rat problem because we’re seeing rats outside,” she said. “If you take a stroll anywhere around Boston or Cambridge, or anywhere in an urban place, you see bait boxes everywhere. And those boxes are out in the open on the streets and sidewalks, and they’re filled with bait that is designed to attract rats. It’s a buffet for rodents.”
In April, speaking to the Boston City Council, Robert Corrigan, an “urban rodentologist” and worldwide expert on rats, said he often sees people relying on bait boxes. Instead, he said, they should be focusing on the root causes of why rats are making themselves known.
Cities should be improving the storage and management of trash at both commercial and residential properties, Corrigan argued, such as high-quality metal or heavy-duty plastic containers.
There’s increased interest among city leaders in discussing alternatives outside of rodenticides, what’s often referred to as integrated pest management, deemed by the EPA as a multi-strategy “environmentally sensitive” approach to dealing with rodents.
An emerging topic of conversation is rodent birth control. Boston is currently running a pilot program in Jamaica Plain that administers contraceptives to rats. Newton began using ContraPest, the first and only EPA approved birth control for rats, in 2021.
As mentioned by Flynn, the New England Pest Management Association president, the city of Boston uses carbon monoxide sprayers to target rodent burrow systems.
More environment news
