Gene Chague | Berkshire Woods and Waters: Rodenticides / pesticides seem to be a heavy burden on birds of prey / animals | Local sports


MassWildlife officials and wildlife veterinarians at Tufts Wildlife Clinic at Tufts University’s Cummings Veterinary Medical Center confirmed that in late July, a young bald eagle succumbed to second generation anticoagulant rodenticide (SGAR) poisoning.

In late July, a young female eagle in apparent distress on the ground in Middlesex County was transported to the Tufts Wildlife Clinic in North Grafton and admitted there. Unfortunately, the young bird died when it was admitted to the clinic. An autopsy was performed at the clinic and liver tissue was sent to a laboratory for toxicological examination. Both the observations from the autopsy and the results of the toxicological tests confirmed that the eagle’s cause of death was due to lethal amounts of anticoagulant rodenticides. This is the second recorded rodenticidal death of an eagle in Massachusetts. The first was an adult bird that died last March. Over 80 pairs of bald eagles nest in Massachusetts.

Anticoagulants Rodenticides are a type of rodent venom that kills by preventing normal blood clotting, causing fatal internal bleeding or bleeding. Wild animals can be poisoned by anticoagulant rodenticides in two ways: 1. Primary poisoning, when an animal eats the bait directly and dies a few days later; or 2. secondary poisoning, when a predator or scavenger eats prey that has consumed the bait. Studies of birds of prey in Massachusetts conducted at the Tufts Wildlife Clinic have shown widespread exposure to SGARs. While bald eagles primarily eat fish, they are opportunistic foragers and will prey or prey on a wide variety of animals.

Gene Chague |  Berkshire Woods and Waters: Bald eagle premature death attributed to rodenticide

Rodenticide the culprit in the death of the bald eagle

As mentioned in my May 8, 2021 column about the death of the first eagle, given the hunting range of eagles, it is impossible to pinpoint the exact source of this rodenticide poisoning. An analysis of the liver tissue confirmed that two different SGARs were taken up by the eagle. For the past 15 years, the US EPA has taken steps to restrict rodenticides. SGARs are believed to be the most harmful to wildlife and cannot be sold through general convenience stores to the typical homeowner. SGARs can still be purchased online in commercial use quantities that can only be used by licensed pest controllers and agricultural users. Other rodenticides, so-called anticoagulant rodenticides (FGARs) of the first generation and non-anticoagulant rodenticides, are only approved for private use by consumers if they are included in a bait station. It is illegal to place poisons outdoors except under strictly regulated permit conditions.

“Not only birds of prey, but many other species of wildlife have been the victims of accidental rodenticide poisoning,” said Andrew Vitz, State Ornithologist, MassWildlife. “Secondary exposure to rodenticides has been documented in other animals such as foxes, bobcats and coyotes.”

He also noted that other predatory wild mammals, as well as unattended dogs and cats, are prone to unintentional exposure.

MassWildlife and Tufts University work together to find practical, environmentally sound solutions to problems related to rodent problems.

To minimize damage to wildlife and pets, MassWildlife and Tufts Wildlife Clinic offer homeowners and other affected citizens the following advice:

“Prevent rodent problems: Remove or secure any food or waste sources that attract rodents. Keep pet, poultry, and livestock feed in pet-safe containers. Make your home rodent-proof! Close or repair any outside openings in your home and other outbuildings that allow rodents to enter.



Big Cat Deaths

This January 30, 2020 photo shows the carcass of a puma found dead north of the Santa Monica Mountains. National Park Service researchers have documented the presence of anticoagulant rodenticide compounds in 26 of 27 local mountain lions they tested, including a three-month-old kitten.



If you have rodents, start with baited snap traps, which allow for quick and humane death and are easy for the homeowner to use. Poisons should only be used as a last resort. If you use poisons, use them in bait stations and follow the directions on the product label. When hiring a business, you choose a licensed integrated pest control company that uses multiple approaches to pest control rather than relying solely on poisons. You can request that the company avoid using SGAR products such as Brodifacoum, Bromadiolon, Difenacoum or Difethialone. “

“The choices we as individuals and communities make about rodent control and waste management practices can help prevent wildlife exposure to SGARs,” said Dr. Maureen Murray, director of the Tufts Wildlife Clinic.

As always, when you find a wild animal and it shows clear signs of injury or illness, it is best to leave it in the wild. If an injury or illness is evident, contact a licensed wildlife rehabilitator for advice before taking action.

Concerned citizens can also help endangered wildlife by sharing this information and advice with friends, family, and others. Connect with groups who work together to find practical, environmentally sound solutions to problems related to rodent problems. “The choices we as individuals and communities make about rodent control and waste management practices can help prevent wildlife exposure to SGARs,” said Dr. Maureen Murray, director of the Tufts Wildlife Clinic.



Cicada Invasion

A red-shouldered hawk holds a squirming Brood X cicada nymph in its beak as it feeds on a Columbia, Maryland lawn last May.



Unknown reasons for massive bird deaths

Readers may recall that MassWildlife reported in mid-July that an unknown disease circulated among songbirds in ten states, some as close as Pennsylvania, New Jersey, and Ohio. Fortunately, it was not found in New England. The disease is said to cause symptoms such as “eye swelling and crusty discharge and neurological symptoms”.

Last month, the Ithaca Times reported that Cornell University experts are not “overly alarmed” by the unknown disease. Elizabeth Bunting, Senior Extension Associate at Cornell Wildlife Health Lab, said a possible cause of the disease was Brood X cicadas.

Cicada Brood X appears underground this year after 17 years. It is one of the largest and most widespread groups of periodic cicadas. They can be found from northern Georgia to New York, west to the Mississippi, and the Midwest. There can be up to 1.5 million cicadas per hectare, bringing the breeding population into the trillions.

The songbirds that ate these cicadas may have gotten sick from pesticides sprayed on the cicadas or fungi that could carry the insects. The pesticides could cause neurological problems and the fungi could be the cause of crusty eyes, Bunting said.

The disease is found in areas where the cicada brood has appeared. In addition, the decline in mystery disease cases has accompanied the retreat of the cicadas.

“Information from the National Wildlife Health Center and several other states said cases were suddenly falling,” Bunting told the Ithaca Times. “That would not be typical of an infectious disease outbreak. One would not expect an infectious disease to go away spontaneously. “

The disease was not found in New England because it did not have the large numbers of cicadas other states had.



Biden Press plane cicadas

A Brood-X cicada that has not shed its nymph skin is seen in a tree on the North Lawn of the White House in Washington in May. Reporters traveling to the UK prior to President Joe Biden’s first overseas trip were delayed seven hours after their charter plane was hit by cicadas. The Washington, DC area is one of the many parts of the country facing the swarm of Brood X, a major populace of noisy 17-year-old insects.



Brian Evens, an avian ecologist at the Smithsonian Migratory Bird Center, also suggests that pesticides could be a cause of the bird decline. “Pesticides are, of course, a possible cause,” he added. “Cicadas have lived underground for 17 years and could accumulate toxins such as pesticides or heavy metals, which the birds could then be exposed to in really high concentrations just because they switched their diet to cicadas.”

Some scientists believe that the correlation between the onset of the disease and the appearance of leafhoppers seems strong. However; Nobody really knows what mechanisms actually caused the disease. Regarding the Cornell Hypothesis, they feel that, while not proven, it is certainly plausible.

The pesticide problem is not believed to pose a risk in our area as we don’t have periodic cicadas or other insects that become so over-abundant. But if it was a fungus, infected birds could potentially carry that part of the disease to New England. They believe that the migration pattern of birds tends to be southward at this time of year, so infected birds tend to stay away from us.

In an update dated July 30th, MassWildlife continues to urge people to refrain from feeding birds or giving bird baths at this time as a precautionary measure against the disease. They are still investigating the situation and asking the public to send them information about dead birds. Birds do not need additional feed at this point in the season. (Removing the bird feeders) will help reduce the interaction between the birds to prevent and mitigate the possible spread of the disease.

Researchers across the country continue to monitor the development of the mysterious disease.

Thank you to the Ithaca Times for some information on this article.

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