A family of loons. Photo courtesy of William Norton.

By Howard Meyerson

Τom Cooley has examined a lot of dead loons during the past 27 years. They appear every year, dead on beaches and inland lakes where cottage owners, researchers, national park volunteers, or Michigan Department of Natural Resources (MDNR) staffers pick them up. The carcasses eventually find their way to the sterile confines of Cooley’s necropsy room.

Cooley is the MDNR pathologist at the agency’s wildlife disease laboratory. His job is to determine why the long-lived birds died, why their haunting calls no longer fill quiet evenings on northern Michigan waters. Cooley has been documenting the cases for nearly three decades. What he’s found is that Common Loons, a Michigan threatened species, die regularly from lead poisoning after ingesting lead fishing tackle. Lead is the third-largest cause of loon mortality in Michigan.

“We’ve looked at 376 [dead] loons over 27 years, not many each year, maybe 11 or 12,” Cooley said. “With lead poisoning, you deal with a sick animal which may go and hide. They may not be as visible as one caught in fishing net, or that flies into something. The numbers may under-represent the (lead) problem, but these are the birds we see.”

Cooley’s records show that 60 loons—16 percent of those examined—died from lead poisoning. Somewhere in the course of their lives they swallowed a lead fishing sinker, a lead jig-head or split-shot, all commonly used by anglers. Loons pick up lead fragments and sinkers in the course of normal feeding. They may swallow a fish with a hook, line, and sinker attached or pick up lead on the bottom while eating gravel to help with digestion.

Other causes

Ninety loons, or 24 percent, died from trauma, the leading category for loon mortality in Michigan. Type E botulism killed 63 loons, 17 percent of the total. A variety of causes killed the rest, including fungal disease, drowning, and mercury. For some dead loons there are

Tom Cooley, conducts a necropsy on a common loon suspected to have died from lead poisoning. Photo: Courtesy of Michigan DNR.

no answers, Cooley said. “When I first started (tracking loon deaths) trauma, lead, or drowning in fishing nets were the main causes, but net designs have changed, and so we don’t see that anymore,” Cooley explains. “Lead poisoning has also dropped a bit, but we pretty much get it every year. Last year, four of 15 loons [seen in the lab] died from lead, five were from trauma, and one was from botulism.”

Concern about the hazards lead sinkers pose to loons is widespread around the world. Restrictions on the sale and use of lead weights for fishing are in place in the U.K., Canada, and several other countries, according to the Wildlife Society, the professional organization for wildlife biologists. Six U.S. states—New Hampshire, New York, Maine, Massachusetts, Vermont, and Washington—have laws that ban the sale and/or use of lead sinkers to protect loons and other birds like eagles. Some have also banned lead fishing jigs.

Other state studies

A 2013 report by Maine Audubon, titled “Maine Loon Mortality 1987 to 2012,” examined the cause of death for 450 loons there. It states, “Lead poisoning from lead sinkers and lead-headed jigs was the leading cause of death for adult loons, responsible for 28 percent of deaths (97 out of 352 adult mortalities) between 1987 and 2012.” The report indicates that other studies show lead poisoning rates from 22 percent for loons in New England states and 44 percent for those breeding adults, to 33 percent in Canada, 36 percent in New York, and 50 percent for adult loons in New Hampshire.

Maine is now phasing in stiffer rules for the use and sale of lead fishing tackle. The sale of lead sinkers .5 ounce or smaller has been banned there since 2002. The new 2013 law bans both sale and use of lead sinkers up to 1.0 ounce and phases in a two-step ban on the sale of unpainted lead jig-heads that are 2.5 inches long or less. The ban on jig-head sale begins in 2016, followed by a ban on jig-head use in 2017.

A young common loon stretching its wings. Photo: William Norton

Tougher rules were needed, according to wildlife managers with Maine’s Department of Inland Fish and Wildlife (DIFW); the .5 ounce sinker ban didn’t do the job. “We determined, based on many years of data where we collected loon carcasses and tested them for lead and opened them up to see if there were any lead objects inside, that it wasn’t just the real small sinkers that were a problem,” explains Danielle D’Auria, a wildlife biologist and loon specialist with Maine’s DIFW. “They were swallowing sinkers close to an ounce in size. And we included jigs because the necropsies by Tufts University were finding them.”

Culprit: lead jig heads 

The majority of lead-poisoned Michigan loons died from lead jig-heads, according to Cooley. They were found in 35 loons, while lead sinkers were found in 13 others. Unidentifiable lead pieces killed four, and three died from ingesting lead split-shot, Cooley’s records show. Two loons died from ingesting lead shotgun pellets and three others had no identifiable pieces of lead left inside.

“A lot of states have gone after the size of sinker and haven’t gone after jigs, but what we’ve seen is that a sinker ban (by itself) wouldn’t have much effect,” Cooley said. “A lead ban was talked about in Michigan (in 2004), but it was shot down pretty quickly.”

Banning lead fishing tackle is highly controversial. The American Sportfishing Association (ASA), a national trade organization, opposes a blanket federal ban. It does, however, support the idea of state-by-state bans where sufficient evidence exists to support it.

“ASA acknowledges that lead toxicosis can kill water birds and lead fishing tackle may contribute to this mortality,” the ASA states in its official position. “ASA recommends that before further laws are enacted to restrict lead fishing tackle on a state or national basis, sufficient data must exist to demonstrate that discarded lead tackle is an actual threat to the sustainability of loon or other waterbird populations. ASA realizes that certain waters may be ‘hot spots’ for ingestion of fishing tackle by waterbirds and encourages any restrictions of lead fishing tackle in those waters to be based on sound science that supports the appropriate action for that water body. Furthermore, ASA continues to encourage and support voluntary angler education programs for the responsible use and proper disposal of lead fishing tackle and urges state and federal fish and wildlife agencies to do the same.”

Legislative solutions are hard to come by, Cooley said. The state of Minnesota, for example, where loons are the state bird, has not been able to get a lead ban passed. “There are too many warring factions,” Cooley notes. “We need to let sportsmen make their own decisions. A lot of states have a ‘Get the Lead Out’ campaign. We can’t do anything about trauma and botulism, but lead is one mortality factor we can do something about.”

Free tackle swaps

Susan Gallo, a wildlife biologist and director of the Maine Loon Project for Maine Audubon, is working to achieve exactly that. The organization led the fight to get lead fishing tackle banned, but it also works in partnership with the DIFW to promote “Fish Lead Free,” a program to educate anglers and provide non-toxic alternatives through tackle exchanges.

Tungsten, tin, and steel alternatives to lead sinkers, split shot, and jig heads increasingly have become available in the market. One company, Loon Outdoors, specializes in non-toxic alternatives for fly anglers, but large fishing outfitters like Cabela’s, Bass Pro Shops, Orvis, and even Wal-Mart carry some.

“I am happy with the sinker ban; that will take care of 90 percent of the sinkers we see [in loons],” Gallo offers. “There is still work to be done on jigs. People think because of the law that if they paint them that is okay, but that’s absolutely untrue. The paint doesn’t last in the gizzard. But the legislation starts moving things in the right direction.”

Maine’s lead ban presents entrepreneurs with a good opportunity, according to Gallo, particularly as the demand grows for lead-free alternatives. “Some say this will put them out of business, but it creates opportunities for a whole crop of new entrepreneurs,” Gallo said. “A lot of small shops are switching over. They [non-toxic alternatives] may not be dirt cheap like lead, but the cost is reasonable and one local store is working with Eagle Claw (a major manufacturer) to offer deals on alternatives.”

Gallo created a “Fish Lead Free” website, blog and logo that she hopes other states will adopt. The website at fishleadfree.org contains updates about loons, lead poisoning, and tackle exchanges in Maine and New Hampshire so far. Wisconsin, she said, is considering getting involved.

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Appears in the July/August Jack Pine Warbler, magazine of Michigan Audubon.