In July and August, biologists will capture, band, and examine loons on several Vermont lakes in an effort to determine the loons’ overall health. Biologists will take blood and feather samples that will be analyzed to determine levels of mercury and lead in the loons.
Mercury contamination of loons has caused increasing concern among biologists in recent years. Mercury levels in loons sampled in other New England states have so far been the highest ever recorded in the U.S. In Vermont last summer, loons and their eggs were tested for mercury on three ponds. Lead is a concern because loons die of lead poisoning after swallowing lead sinkers and jigs used for fishing.
Because loons are so elusive, a team of biologists will work late at night by boat, locating birds with bright lights and capturing them in large nets. Once their heads are covered, the birds calm down while being banded, weighed, sampled, and then released. More than 2,000 adults loons in the United States and Canada have been sampled without serious injury–a remarkable record.
The bright lights associated with this research procedure should not cause alarm for lakeshore residents. Signs will be posted at boat launch areas of the waterbodies where the research will be done.
The study is being conducted by biologists from the Vermont Institute of Natural Science (VINS), Vermont Department of Fish and Wildlife, BioDiversity Research Institute, U.S. Fish and Wildlife Service, and the U.S. Geological Survey’s Biological Research Division.
For more information about this long-term research project, contact VINS loon biologist Eric Hanson at 802-472-6905. To exchange lead fishing sinkers for non-lead samples and receive an informational brochure about water birds and lead, contact the Vermont Agency of Natural Resources, Department of Fish and Wildlife’s main or district offices. For a list of lead sinker exchange sites in the Northeast Kingdom of Vermont, call Mark Lorenzo of the National Wildlife Federation at 802-229-0650 or Ross Stevens at Brighton State Park.