Lake Vermilion’s loon population appears to have dipped noticeably this year, but it remains unclear whether the decline represents normal variation, or is part of a troubling trend.

“One thing we do know is that the oil spill has nothing to do with it,” said longtime loon count coordinator Mardy Jackson. While the oil spill could well take a toll on Minnesota’s loon population in future years, its impact wouldn’t be felt before next year at the earliest, said Jackson.

This year, counters found 221 loons. While that still represents the highest total in the state, it was down 60 birds over last year’s total count of 281 loons. This year’s count included 198 adults and 23 chicks, which put the chick count down just six from last year.

Jackson speculates that chick production may have been hampered by the rebound in water levels in late May and June, which could have flooded some nests. “Quite a few pairs were found without chicks, so that could be part of it,” Jackson said.

Jackson and other loon counters are also worried that loons could be feeling the effects of Vermilion’s burgeoning cormorant population. Jackson noted that count territories in and around Big Bay saw the most dramatic declines in the numbers of loons— and that’s where the lake’s cormorant population is centered. While Jackson acknowledges that the link is only speculation at this point, “I think it’s something to be watched,” she said.

This year’s drop in loon numbers could be nothing more than the usual fluctuation seen sometimes in the past. And chick numbers were actually better than in some recent years. In 2002, just 13 chicks were spotted, while only 14 were counted in 2004.

On a statewide basis, the loon population appears to be stable at about 12,000 birds, according to Maya Hamady, with the Department of Natural Resources’ nongame wildlife program. The DNR maintains a loon monitoring program that incorporates reports from dozens of lakes across the state, providing a good sample of the loon population. That will be particularly helpful in the next few years as researchers attempt to gauge the impact of the spill in the Gulf of Mexico. “It will tell us a lot about the impact of the oil spill, because it’s already statistically set up,” said Hamady.