SARANAC LAKE - Scientists and members of the public gathered at the Lake Colby boat launch on Wednesday night for loon banding observation night.
The event provided members of the public an up close look at both an adult and a juvenile loon, while scientists were fast at work gathering blood and feather samples from the birds for a variety of tests.
Dr. Nina Schoch, a scientist and vetenarian who heads the Biodiversity Research Institute's Adirondack Center for Loon Conservation, said her organization will test the blood as part of a study on mercury pollution in aquatic ecosystems. The loons, whose overall population is the Adirondacks is strong right now, are being used as an indicator species.
A loon reveals its ankle band as it lifts its leg to scratch itself in September 2011.
(Enterprise photo — Lou Reuter)
"The blood sample tells us about short-term dietary intake and how much mercury they've ingested in the last month or so," Schoch said. "Then we're taking feather samples also, and those tell us more about the long-term lifelong mercury in their body."
Mercury contamination in the Adirondacks, which has been a problem for decades, comes mainly from emissions from coal-fired power plants in the Midwest and elsewhere.
BRI staff also put color bands on loons. The banded birds are then monitored on a weekly basis to determine their reproductive successes.
"Some of the birds we've been monitoring since 1998, and we relate the reproductive success (or failure) of the birds to their mercury levels," Schoch said. "We've been able to document that the high-mercury birds are producing far less chicks than the low-mercury birds, and it's primarily because they're hatching fewer chicks."
Schoch said the loons with high mercury levels are nesting at the same rate at other birds, but the number of eggs that hatch chicks is lower.
"It's probably because the higher-mercury birds are also depositing mercury in those eggs, and they also aren't incubating the eggs as well as the low mercury birds," Schoch said. "Mercury is a neurotoxin, so it makes them more depressed and lethargic and they don't defend the territories well. They don't incubate the eggs as well."
Findings such as these related to mercury were part of a report that was released to the public earlier this summer. The study was performed by BRI, based in Gorham, Maine, and the Wildlife Conservation Society.
On Wednesday, in addition to the BRI representatives, scientists from WCS and one from Calvin College took part in the activities.
Schoch said Keith Grasman of Calvin College would be testing blood samples to study how loons immune systems relate to mercury levels.
WCS was looking at the overall health of the birds, and will do a complete blood count and biochemical profile.
The loons were captured with the help of the state Department of Environmental Conservation, which provided two boats and staff to capture the birds. After the birds were captured, they were brought to the boat launch, where the samples were taken. The birds were then released back into the water.
Schoch said while the birds are stressed in the short term by the testing, they have proven to do well in the long term. The majority of the tests were performed on the adult loon while the young loon sat in the lap of Lake Colby resident Lee Keet. The young loon appeared pretty relaxed most of the time.
Schoch said the group bands and samples loons for about one week each summer, visiting one or two lakes per night. Overall, they have 80 study lakes. Each is visited about every five years.
Much of the information gathered from the samples Wednesday night will eventually be put into long-term reports, like the one that was released to the public earlier this summer.
In addition to mercury, threats to loons include human disturbance of nests, ingestion of lead fishing tackle and getting caught in fishing line, Schoch said.
"This year, since May, we've had calls on 16 birds that potentially needed rescue, and more than half of those were entangled in fishing line," Schoch said.
To combat the fishing line problem, Schoch is developing a fishing line recycling program. She will be assisted by local Boy Scouts and will reach out to fish and game clubs throughout the Adirondacks for additional help.
Contact Mike Lynch at 518-891-2600 ext. 28 or firstname.lastname@example.org.