Eat lead and you're dead.
Ingesting just one lead sinker or jig can kill a loon. When lead is eaten by a loon it's ground up in the gizzard and absorbed into the blood and tissues of the bird, poisoning it.
Loons aren't the only birds affected by lead poisoning. Trumpeter swans, bald eagles and osprey all rely heavily on fish for food and are susceptible to lead poisoning, too. Eagles and ospreys do not have gizzards and tend to regurgitate lead. But eagles can eat lead bullet fragments when feeding on dead deer.
Animals with lead poisoning suffer physical and behavioral changes, including loss of balance, gasping, tremors and, in the case of birds, impaired flight. Weakened by toxicity, they're more vulnerable to predators and can have trouble feeding, mating or caring for their young.
Poisoned birds and animals often die within two to three weeks after ingesting lead. All wildlife is negatively affected by lead in our air, land and water.
Biologists have studied the effects of lead sinkers and jigs on birds since the 1970s. Where loons breed, lead poisoning from sinkers or jigs may account for up to 50 percent of the dead adult loons, researchers say.
Between 1980 and 1996, The Raptor Center reported lead poisoning in 138 of 650 eagles it treated. From 1996-99, 43 more eagles were found with lead poisoning. Often the source of the lead cannot be detected as the birds have cast the material out of their system. TRC reports there has been no reduction in lead poisoning of bald eagles despite the restrictions on lead gunshot for hunting waterfowl.
Minnesota loons found dead in 2004 are being kept for future necropsy analysis. Dead loons found this year will be added to the cache. In Michigan, where lead poisoning has helped put loons on the threatened species list, other research is being conducted.
A high incidence of lead poisoning in loons -- 57 percent of total mortality -- was found in a long-term New England study conducted by Mark Pokras of Tufts University in Massachusetts. For more than 15 years Tufts Wildlife Clinic has performed necropsies on over 600 common loons, yielding much valuable information on causes of mortality to loons.
Findings have led to legislative bans on the sale and distribution of lead fishing gear in Maine and New Hampshire. Maine banned the use of lead sinkers and jigs that weigh less than an ounce and are smaller than an inch. Great Britain banned the use of lead sinkers in 1987. In Canada it's illegal to use lead fishing sinkers and jigs in some national parks and wildlife areas.
The Minnesota DNR is encouraging anglers to replace the lead on a voluntary basis. There are many non-toxic lead alternatives that are made from bismuth, tin, stainless steel, tungsten, ceramic, recycled glass and natural granite.
Lead tackle exchanges are scheduled for July 23 from 10 a.m. to 3 p.m. at Paul Bunyan Nature Learning Center, Highway 371 and County Road 49 in Baxter, and for Aug. 20 from 10 a.m. to 3 p.m. at Gander Mountain at 385 Edgewood Drive in Baxter.
Because weights of different materials vary, you'll have to experiment a bit to find what works best for your type of fishing. Don't be quick to jettison the new tackle. Be patient and wildlife will benefit.
Environmentally-friendly unleaded sinkers, such as Gremlin Green and Bullet Weights, have been available for several years. This year two new tungsten-composite sinkers were introduced that have added advantages. Gravity Heikkita offers new snap-on weights and Dr. Drop, Inc. now has an exclusive "friction grip" feature that allows for fast attachment and retrieval.
To insure future generations continue to experience the sight of an eagle soaring or the sound of loon calling, we need to do more to safeguard the environment. Even if you don't fish, share this information with family and friends who do. Just tell them to "get the lead out!"
For more information on lead poisoning in birds contact:
* Tufts Cummings School of Veterinary Medicine at www.tufts.edu/vet/loons/index.html
* Minnesota Office of Environmental Assistance at www.moea.state.mn.us/sinkers
* DNR nongame wildlife program at www.dnr.state.mn.us
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