The resurgence of the once endangered bald eagle population is one of the country’s great nature conservation success stories. However, a new threat to the survival of birds of prey is imminent, which is surprisingly near home.
First patient to arrive at Willow Brook Wildlife Center In 2022, there was a bald eagle rescued from a forest reserve in Cook County by a bird collision monitor in Chicago.
Dr. Sarah Reich, the center’s chief veterinarian, observed one of the known pairs of birds sitting straight in a puddle in the snow for three hours, which is not normal behavior. .. When the eagle arrived at Willowbrook, a unique facility in DuPage County with full veterinary staff, Reich saw it covered in a large amount of blood.
“One of our first concerns was that it was shot,” Reich said. X-rays excluded it and fractures. The veterinary team was confused. Why were birds of prey so debilitated?
“This eagle wasn’t cheeky, it’s not typical,” Reich said. Birds have a reputation for being aggressive in captivity, and handlers need to be equipped with protective equipment.
Looking into the eagle’s mouth revealed a thin gum, a sign of anemia, which was confirmed by testing. The red blood cell count of birds is half the original level, and the Willow Brook team has become suspicious of the cause.
“One of the only reasons we see where birds bleed out of control is RodenticideReich referred to a class of chemicals colloquially called rat toxins, saying that “anticoagulant rodenticides prevent coagulation.”
After taking blood from an eagle and putting it in a tube, the team waited for it to clot. And waited. And waited.
“A normal bird should coagulate within 3-5 minutes. This bird I left for the day, but it hadn’t coagulated yet after 7 hours,” Reich said. .. “It’s decisive to say that this animal had an anticoagulant rodenticide. Perhaps this bird had small, small, small small cuts, and the cuts just kept bleeding. rice field.”
Bloody defecation later provided evidence that the bird was bleeding not only on the outside but also on the inside.
“He would have been dead,” Reich said.
In the 1960s, there were only 400 breeding pairs of bald eagles in the 48 states of the continental United States. The main cause of their decline was the pesticide DDT: spillage from farmland caught in fish eaten by eagles. One of the side effects of DDT is that the eagle causes the eagle to lay eggs with very thin shells and the nest fails. American Bird Conservation Society..
DDT was banned and eagle was given a lot of protection under the Endangered Species Act, the number of which recovered until the birds of prey were removed from the endangered species list.Thousands today Eagle spends winter in Illinois, Represents one of the largest delegations outside of Alaska.
DDT is no longer a problem for eagles, but other deadly toxins such as lead, mercury, and rodenticides have emerged as a concern. They mainly target rats and mice, but also kill squirrels, chipmunks, woodchucks, voles, porcupines, beavers, and nutria. These pesticides have different active ingredients and work in different ways. For example, some attack the nervous system of rodents, but anticoagulants have been scrutinized as dangerous to eagles and other wildlife.
The names of the anticoagulants contained in rodenticides may sound familiar. Warfarin (or its brand name, Kumazine) was used early on until rodents became resistant to it. “It’s weird,” Reich admitted. What was prescribed to humans to prevent blood clots would have a more evil purpose as a poison.
Later, a second-generation anticoagulant rodenticide was developed. Brogifakum and Bromadiolone are the two most common and much more powerful. They work by blocking enzymes that help recycle vitamin K, which is needed for coagulation. The absence of enzymes means that the body will eventually lose vitamin K. The absence of vitamin K means that there is no coagulation.
A small ridge would cause bleeding in the poisoned animal, Reich said.
The Eagles should be careful, but don’t eat rodenticide, Reich said. The problem is that they eat rodents that feed on them. Or eat what you ate the rodents that ate the food. Anticoagulants Rodenticides are so powerful that they stay in the animal for a long time and therefore cross the food chain.
“They can not only kill things better, but they can get stuck for much longer,” Reich said.
Some eagles suffer acutely and react immediately to toxins. Reich said that others gradually accumulate low levels, where they snack between mice and mice there, developing cases of chronic poisoning. “Ultimately, it bleeds because it coagulates so slowly, but it can take months or a year to happen.”
Reich understands that asking people to give up pest control is “100% unsold.” Her suggestion is to read the container, check the active ingredients of brodifacum and bromadiolone, look for the term anticoagulant, and perhaps choose another option. Alternatively, go to the root of the snap trap. This is another more humane way.
“It’s always a good conversation for people. If you try to use these (rodenticides) on mice and rats, they will continue to poison wildlife,” Reich said. “Rats and mice are not killed immediately. They go to eat their diet (poison bait), go three days later and die. So what happens between the three days after their ingestion? It may have been eaten by multiple creatures. It’s amazing for some. “
The good news for the eagle caring for Willow Brook is that the treatment to neutralize the anticoagulant rodenticide is fairly easy. Is to administer vitamin K.
Blood transfusions may be required, but for now no blood transfusions are required. Reich said the poisoned eagle was already “much more sassy” and was flying around the enclosure.
She said it usually takes a month for anticoagulant rodenticides to circulate in the animal’s system, at which point Willowbrook’s staff conducted the same tests that were initially used to diagnose coagulation problems. increase. When the bird’s blood clotting time is checked and rechecked and then gathered, the birds of prey are returned to the forest to reunite with their companions. The staff is thrilled to see it work.
“Wild animals don’t want to be around people. They don’t want to have anything to do with us,” Reich said. “In a month and a week, he’ll be back there.”
Bald eagle being treated at a suburban wildlife center after rodenticide bleeding | Chicago News
Source link Bald eagle being treated at a suburban wildlife center after rodenticide bleeding | Chicago News