I spent two days last week camping and bicycling around the Hero Islands and Isle La Motte and was pleasantly surprised at the number of loons I observed from my bicycle seat. There were at least 12 loons along the east coast of the islands (known as the Inland Sea). What made the observations even more satisfying is that I was not intentionally searching for loons; they were just there when the roads came near the water. Thus, there were likely more than 12 loons in the area. I also heard yodeling, the male territorial call, coming from the Savage Island region. There have been reports of loons nesting on Lake Champlain, but we still have not confirmed any nests or chicks.
Back in 2002, I spent nearly 3 weeks in June and July conducting loons surveys on Lake Champlain, and I only observed 2 or 3 loons in this entire NE section of the lake. With the help of 25 volunteer observers on Loonwatch day, we did estimate that there were at least 30-40 adults and 15-20 subadults on the entire lake during mid-summer. Now in mid-September, it could be that loons are already moving to Lake Champlain in preparation for migration, especially non-breeders and breeders without chicks. However, most loons really do not start moving from their territorial waters until later September and October.
Where do these loons come from? We know that one loon from the Adirondacks with an implanted satellite transmitter stopped on Lake Champlain for a day on its way to the Cape. Since loons tend to eventually return to their natal lake areas, I would guess that most loons observed on Lake Champlain are either from the Adirondacks or Quebec. Vermont loons likely stay to the east side of the Green Mountains. This summer we captured a loons in Williston (stuck on a water retention pond at Tafts Corners shopping center) that was very small indicating it was from central or northern Quebec. Loons become smaller the further they are from coastal areas. Ted Murrin, an avid Vermont birder, has counted over 500 loons in one day migrating along the shores of Lake Champlain in late October.
Next time you are on the shores of Lake Champlain, keep your eyes peeled (and enter your sightings on VT ebird). During the next two months, scores of loons and other birds will be flying south over Lake Champlain's waters. ** Eric Hanson, Vermont Loon Recovery Project Coordinator
5 comments:
Eric,
What's the reason for the size difference in inland loons?
Susan,
Breeding loons in the interior part of North America are smaller than loons that breed near the coast because it is likely more efficient for long-distance migration. There is a trade-off however, as larger loons can better acquire and defend territories. Eric
Woke up to the sound of a loon from my South Hero home today. Motivated me to get ip!
Is this a gradual difference, so in a given area everybody's about the same size?
Susan, There is some variability in loon size within regions. Weights can vary up to several pounds e.g., 11 pound male and 13 pound male could live on adjacent lakes. However, we probably won't see 8 pound male loons in Vermont like you might find in the midwest. Loons spend the first few years on the ocean and then return to their natal lake region dispersing from there. Most male loons return within 20-30 miles from the lake he hatched on; females disperse a bit further (all this based studies of banded loons in Wisconsin). So there is also a strong genetic aspect to where a loon will spend the summers.
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