FREEDOM — Diane Winn has three patients who are suffering from lead poisoning, and the prognosis for their survival is poor.

The patients are a golden eagle, a bald eagle and a Canada goose that Winn is working hard to rehabilitate at the nonprofit Avian Haven in Freedom.

Most of the problem with lead poisoning of birds could be resolved, said the executive director of the rehab facility, if hunters stopped using lead ammunition. Scavengers such as eagles can ingest toxic bullet fragments when they eat the scraps of meat or gut piles left behind by hunters.

“The solution is simple: switch to nonlead ammunition,” Winn said. “Or, to protect wildlife, don’t leave any remains in the field. Because the hazards of lead exposures are very well known, our society has gone to great length to eliminate lead from many materials, but lead ammunition is still widely used.”

In October, California became the first state to ban lead in hunting ammunition, which must no longer be in bullets shot in the state by July 2019.

The use of lead ammunition has been banned from waterfowl hunting by the federal government since 1991.

However, the executive director of the Sportsman’s Alliance of Maine, or SAM, said lead ammunition is not the biggest factor in lead poisoning in birds. And, he said, getting rid of lead ammunition is not the answer.

David Trahan of SAM said he knows the work of Winn and Avian Haven and that he and his wife even volunteer there.

“I can’t say enough about the work they do,” Trahan said. SAM even sent a letter of support to the organization when it was seeking a grant to expand its facilities.

The greatest source of lead in birds, he said, has been from small sinkers used in fishing.

More than a decade ago, Maine lawmakers banned lead fishing sinkers weighing a half ounce or less, and just last year passed legislation expanding the ban to the sale and use of sinkers weighing one ounce or less.

In fighting for the legislation, Maine Audubon pointed out that lead poisoning is the leading cause of death among adult loons in Maine and is responsible for nearly one-third of the documented mortality over the past 25 years.

Trahan said the sportsmen group has worked with the Audubon society to change sinkers from lead to steel.

“Sportsmen have been very sensitive. We have done what we can but this is a different debate,” Trahan said about banning lead ammunition.

The difficult challenge would be to find a suitable replacement to lead, he said. There would have to be a lot more testing of nonlead bullets, he said, noting that they could affect the inside of the barrel of firearms or affect the accuracy of firearms. In addition, Trahan said he would want to know if a lead replacement would be as effective in killing an animal quickly and humanely.

If a suitable replacement was found that was close to the ballistics of lead, the market would then drive people to buy that substitute, he said.

“All those questions need to be answered before we just leap into getting rid of lead,” Trahan said.

Trahan said he would support a proposal to provide nonlead ammunition to game wardens for when they have to put down deer or moose wounded in vehicle accidents.

Trahan said that one area the organization can work on is education of its members about proper disposal of the carcasses of game or pest animals that have been shot. He said the area of the carcass that has the bullet fragments need to be either buried or disposed so that eagles won’t eat tainted meat.

Sportsmen want to protect eagles, he said.

Winn said her concern is for the health of the birds. She said while an eagle might ingest lead from eating a fish with a lead sinker still attached or from eating a loon that has swallowed a fish with a sinker, that has not been her experience in treating birds.

“All of the lead-poisoned eagles we’ve admitted over the years with lead still in their GI tracts have ingested tiny fragments that most likely resulted from a projectile splintering from bone impact. We have never seen anything resembling an entire sinker, or part of a sinker, in an eagle,” Winn said.

The nonprofit Avian Haven was created in 1999 by Winn and her partner Marc Payne. It was in the news this week for taking in a snowy owl that was removed from a building in downtown Portland.

The center’s annual caseload has increased from about 300 in its first full year to about 1,300 this year, making it one of the largest rehabilitation centers in New England, according to Avian Haven’s website. Funded through donations, the organization has cared for nearly 12,000 birds since its inception.

“It’s a calling,” said Winn, who has been involved with bird rehabilitation since 1997 and whose partner has been doing this work for a lot longer.

The bird rescue center each year typically sees two to three loons, three to four eagles, and two to three ducks with lead poisoning, she said.

She said it only takes a tiny amount of lead to kill an eagle.

Winn said most of the birds admitted with lead poisoning die.

The primary treatment for birds with lead poisoning is chelation therapy, which involves giving them medicinal compounds that bind to heavy metals such as lead that is in the blood and removes it from the system. She said the cost to treat a bird varies, but one five-day chelation therapy treatment for a bald eagle can cost about $50.

The time for an eagle to recover varies based on the nature of its injury and illness but can range from a few weeks to more than a year. She said even a small amount of lead can affect an eagle’s motor skills and lead it to become injured in other ways such as colliding with a motor vehicle.

The current eagles that are patients are not yet able to fly and their prognosis is not yet known.

“The golden is still in an indoor cage; we’ll know more about prospects for recovery when he goes outside to a larger habitat,” she said.