Wildlife caregivers stunned after three bald eagles poisoned by lead
WILTON - The bald eagle found in distress on Wilton Lake that died two days later from ingesting lead ammunition fragments was hard news for local residents who had come to appreciate the bird's majestic presence.
But, it was even more difficult for the wildlife rehabilitation center staff who tried to save its life, because Wilton's eagle was just one of three in Maine brought into Avian Haven, a wild bird rehabilitation center in Freedom during two weeks last month. All three were found to be suffering from lead poisoning after the eagles ingested ammunition fragments believed to be found in scavenged hunter kills. Three eagles arriving within such a short period of time was alarming because they might not see that many in any given year.
"It's heartbreaking and discouraging," said Diane Winn of Avian Haven.
On Jan. 19, Maine Game Warden Dan Christianson responded to the report of a bald eagle that had fallen out of a tree and had remained grounded on Wilson Lake. Christianson retrieved the bird and took it to the center.
Winn suspected lead poisoning right away as the eagle, determined to be an 18-year-old from Massachusetts according to its gold band's information, displayed symptoms of incredible weakness, lack of coordination and an inability to fly.
Even tiny specks of lead, which is soft and breaks into into small pieces easily on impact, can rapidly - within hours - affect a number of body systems. Nerve damage causes the bird appear clumsy and its red blood cells are prevented from carrying oxygen. Hardest to watch, Winn said, is when the eagle's respiration becomes incredibly labored. With its head back and beak open wide, a wheezing sound can be heard as it struggles to get enough oxygen, but can't.
Wilton's eagle arrived and underwent treatment immediately for lead poisoning. Its gastrointestinal track was flushed in the hope any lead fragments could be removed before damage is done.
"We got a piece of lead out," Winn said. The lead fragment, confirmed coming from ammunition, was a half centimeter in diameter, or 40 milligrams, an amount lethal to a bald eagle if it remains in its intestines.
The eagle was given a chelating agent, a chemical that bonds to heavy metals to reduce its damage to the body's tissues, x-rayed and its blood tested to monitor its condition. See the process at Avian Haven here. (Please note: Some of the video footage of an eagle in respiratory distress may not be suitable for everyone.)
"After that, it's wait-and-see for how much damage has already been done," she said.
Two days later, the Wilton eagle died.
The center's entry on the day the eagle died, which was determined to be caused by lead ammunition fragment ingestion: "Safe and warm, well-cared-for and helped in every way humanly possibly, this beauty put her head down this afternoon and peacefully slipped away. Thank you all so much for your prayers, good wishes, positive thoughts ... we all did what we could. Fly away Home, sweetheart."
The other two eagles brought in, one from the Boothbay area and the other Bowdoinham, are still alive but it's not yet known to what extent the damage from lead ingestion may be. Even if they both survive, it's still unknown whether they will ever be able to be released into the wild, Winn noted. Damage to the central nervous system can be permanent, resulting in the eagles unable to fly when wings won't function correctly.
The problem of lead poisoning is "so easy to solve," Winn said, "just switch to non-lead ammunition."
Venison is often donated by generous hunters to the center. All of it is x-rayed before it's fed to recovering predator birds because even the tiniest lead fragment that can't be detected by sight or feel, is deadly.
"There's no way to know unless you have it x-rayed," Winn said, adding that it's "not unusual" that a lead fragment is picked up in donated deer meat. In that case, she surmised, people may be unintentionally serving lead at the dinner table.
Rep. Lance Harvell of Farmington, a legislator and lifelong hunter, doubts that deer meat may be tainted as often as Winn described in the donations to the center.
By and large, Maine hunters use rifles to hunt deer. These days, bullets are made of lead with a copper jacket which Harvell said most often pass through the animal and don't leave fragments. Some people do hunt using buckshot which may be lead, particularly in suburban areas where hunters need to be closer in range to their target for the shot to be effective, he added.
With lead poisoning the leading cause of loon deaths in Maine, according to Maine Audubon data, last summer the Legislature passed a bill that went into effect on Sept. 1, 2013, banning the sale and use of lead sinkers weighing one ounce or less. The law will also prohibit the sale and use of bare lead-headed jigs that are 2.5 inches long or shorter when that portion of the law takes effect in 2017.
In October 2013, California was the first state to ban the use of lead ammunition for hunting. California's law goes into effect in five years, with phased-in regulation beginning next year. A ban was already in place in several counties in that state home to the endangered California condor, which is known to scavenge hunters' kills. Over the years, a high number of condor deaths has been attributed to lead poisoning from ammunition fragments, according to supporters of the ban.
In 1991, the U.S. Fish and Wildlife Service banned lead shot for use in waterfowl hunting and now steel ammunition is used at an alternative. Citing environmental concerns, the military announced plans to phase out lead bullets by 2018.
Supporters of banning lead ammo say it will protect wildlife, the hunting families who routinely eat game, along with ground and water contamination from missed shots. Lead has been banned from gasoline and paint because of human health safety concerns.
Besides the generally higher cost of copper ammo versus lead, Harvell said he's tried using solid copper bullets when hunting and found them not to be as effective in the kill. Copper bullets are lighter than lead and not as accurate nor do they expand as lead does as it passes through the body cavity, he explained. Currently, lead bullets have copper jackets which acts to keep bullets intact and cause rapid death.
"Lead has been used for many years and if it were affecting health negatively, you'd think we'd have seen there was a problem by now," Harvell argued. "I've been hunting all my life and I would have seen it."
"Everybody knows lead is bad," Winn countered, "yet people are using lead ammunition as if it's fine."