Jeff Green | Jul 02, 2009
Back to HomeFeature Article - July 2, 2009 In the land of the silver birch, the stab of the loonBy Jeff Green
The Frontenac Stewardship Council held a highly successful all-day loon workshop at the Oso and Anglican Church halls in Sharbot Lake last Saturday. The workshop featured Dr. Charlie Walcott of Cornell University and Kathy Jones, Director of the Canada Lakes Loon Survey of Bird Studies Canada.
Other contributions came from the Nature Lover’s Bookstore in Lanark and Ontario Power Generation, which built a loon nesting platform that was used as a door prize.
Among the 120 plus people who attended the event were representatives from 12 lake associations, all interested in the life cycle of the iconic lake birds, and in their continued success as a species.
According to Kathy Jones, loon populations are stable in Canada. Canadian lakes are ideal habitat for the loons, which are a circumpolar species. While there are threats to loon populations, including loss of habitat, lead sinkers in fishing gear, the impact of acid rain on fish populations, and the impact of human activity such as boating, Jones said there is no indication that the peaceful call of the loon will cease to be heard on our northern lakes.
Loon calls, however, are not quite as peaceful as they might sound to human years. According to Charlie Walcott, who has been studying loons in Wisconsin for the past 16 years, most loon calls are designed to communicate territorial claims, and they are part of a complex set of interactions that are designed to establish which pair of loons will inhabit specific breeding grounds.
Loons are pretty well focused on the real estate business, and their maxim seems to be location, location, location - often with deadly results for male loons trying to protect their territory from other intruding males.
Professor Walcott showed clips of battles between female loons over nesting territory. In all the cases that his research team have studied, the losing female in a battle for territory departs bruised but unharmed.
When males battle for territory, however, the result is fatal for the loser 30% of the time. More ominously for older, established males, in cases when the intruder to a territory loses, the intruder tends overwhelmingly to survive, but when the incumbent loses, they tend to go down with the ship, so to speak. While death sometimes occurs after the battle is over, it is commonly the result of a stab wound to the heart delivered by the pointy beak of the intruder.
The male and female loon that win the desired territory for another year, seem happy to mate with one another.
Their philosophy, according to Walcott is “If you are here, I love you.”
So much for the idea that loons mate for life.
Walcott's research has focused on some smaller lakes because they tend to have a single nesting pair, while larger lakes, particularly those with many secluded bays, can have multiple pairs.
The research has shown that it is the male who chooses the nesting site, and the primary logic seems to be “If it works, do it again.” The first year that a male loon has dominion over a given territory, the hatch rate is about 47%. That rate rises to 80% after a few years.
According to Walcott, the most dangerous time for a loon is before it hatches, because of predation. Once they hatch, they have a pretty good chance of surviving.
Loons are also not very sentimental parents. In the fall, loons tend to hold what he calls “social gatherings that can number up to 15 or 20 birds or more, up to 75 I once witnessed, and we have no idea why.”
After a time the “social gatherings” tend to break up, and loons head off to the south in small groups, ranging from 2 to 10 loons in a travel party. Adult loons leave earlier than their offspring, who are left to fend for themselves, and who tend to wait until the last minute, before the lakes ice over.
Loons will return to their birthplace to start the territorial and mating battles all over again. Charlie Walcott's research has shown that males generally return to within a mile of their birthplace while females range about 15 miles.
This is a bit similar to the habits of some of the people in the audience at the workshop, who go off to disparate locations in the south each fall, only to return to the same cottage each spring or early summer.
Kathy Jones talked to the audience about their role in keeping the loon population healthy in our lakes. Maintaining shoreline in a natural state is crucial, as is water quality since the loon diet is composed mainly of fish.
In the afternoon she talked about loon nesting platforms in detail. These are rafts that are covered with a variety of vegetation to approximate tiny offshore islands. The advantage they bring for loons is to give them a suitable nesting habitat that is hard for many land predators to reach.
It generally takes two or three years for nesting platforms to be used by nesting pairs of loons, and their location is important as well. They are tethered to the shore and loons tend to prefer them to be a bit of distance from the shore.
After the presentations of both Kathy Jones and Charlie Walcott, audience members were full of questions and comments about their experiences with loons over the year.
While the myth of the peaceful loon may be just that, interest in these iconic lake birds is only piqued by information about their social and reproductive habits.