The image of feathers of forest green, ebony and snowy white splotches, stripes and dots and an eye of burgundy wine on rippling blue water transports you to the quietude of a northwoods lake. If you have never seen a loon up close, here's your chance. This year's stunning DNR Nongame Wildlife poster zeros in on the head of an adult with a solitary drop of water rolling off its beak.
However, along with the spectacular photo comes a message that's not so pretty. It's about loons and lead poisoning, which obviously is the bad news. The good news is that you can lessen the chances that loons on your lake will fall victim to lead poisoning.
Loons routinely swallow small pieces of gravel from lake bottoms. The gravel passes to their stomach and helps in digestion, like grit in the stomach of a chicken. When lead fishing sinkers are lost in the course of fishing and drop to the bottom of the lake they can be picked up by loons. Some loons also eat fishing jigs they mistake for minnows. As lead is exposed to stomach acids it enters the bird's system and slowly poisons the bird.
Not only are loons affected, but so are other waterfowl such as the trumpeter swans we've worked so hard to reintroduce to Minnesota. Bald eagles and osprey, which heavily rely on fish for food, are especially susceptible to lead poisoning.
Like other "heavy metals" lead is toxic. In sufficient quantities it can have adverse affects on nervous and reproductive systems of mammals and birds. An animal with lead poisoning will have physical and behavioral changes, including loss of balance, gasping, tremors and in the case of birds, impaired ability to fly.
Wildlife weakened by such toxicity is more vulnerable to predators and may have trouble feeding, mating or caring for its young. Weak and emaciated poisoned animals often die within two to three weeks after ingesting lead. It doesn't take much stretch of the imagination to recognize all wildlife is negatively affected by the presence of lead in our air, land and water.
The Minnesota Pollution Control Agency did a study on loons to examine them for high mercury concentrations. The mercury study incidentally discovered that loons were dying from lead poisoning. Out of 101 dead loons that were analyzed, a total of seven died of lead poisoning and an equal number died of fish line entanglement. The fish line problem is fairly straightforward and can be reduced by urging anglers to avoid throwing waste fish line and tackle in our lakes or along the shore.
Biologists have studied the effects of lead sinkers and jigs on water birds and birds of prey since the 1970s. In areas where loons breed, lead poisoning from sinkers or jigs may account for up to 50 percent of the dead adult loons found by researchers.
Between 1980 and 1996, the Raptor Center reported lead poisoning in 138 of 650 eagles they treated. From 1996-99, 43 additional eagles were found to also be affected by lead toxicity. Most times the source of the lead cannot be detected, as the birds have cast the material out of their system. The Raptor Center reports there has been no reduction in lead poisoning of bald eagles despite recent restrictions on lead gun shot for hunting waterfowl.
Now for some good news. A high incidence of lead poisoning in loons (57 percent) was found in a New England study. As a result, both New Hampshire and Maine have enacted restrictions on lead tackle. Great Britain banned the use of lead sinkers in 1987. In Canada, it's illegal to use lead fishing sinkers and jigs in national parks and national wildlife areas. The U.S. Fish and Wildlife Service is also considering restrictions of lead fishing tackle on national wildlife refuges where loons and trumpeter swans breed.
The Minnesota DNR encourages anglers to replace the lead in their tackle boxes on a voluntary basis. Currently there are many non-toxic sinker alternatives on the market made out of bismuth, tin, stainless steel, tungsten, ceramic, recycled glass and natural granite. Because weights of the different materials vary, you'll have to experiment to find what works best for your type of fishing. Don't be quick to jettison the new tackle. Be patient and all wildlife will benefit.
Ask your local bait and tackle store to stock environmentally-friendly unleaded sinkers. Two examples are Gremlin Green and Bullet Weights. Some major discount stores have made a special effort to increase the variety and supply of non-lead sinkers.
Remember to never throw old tackle into the water or on shore. Consider lead sinkers and jigs as toxic material and dispose of them at proper household hazardous waste collection sites.
To insure that future generations hear the call of the loon we need to do more to safeguard their environment. Even if you don't fish, share this information with family and friends who do. Just tell them to "Get the lead out!"
To get the informative poster from the Nongame Wildlife Program, look for the loon on your state income and property tax forms. Many people refer to this program as the Chickadee Checkoff. For more information on the program or poster, contact Pam Perry, Regional Nongame Specialist, DNR Regional Headquarters, 1601 Minnesota Drive in Brainerd (218-828-2228 or e-mail firstname.lastname@example.org); the Nongame Wildlife Program, Box 7, 500 Lafayette Road, St. Paul MN 55155; or check out the DNR website (www.dnr.state.mn.us).
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