08/19/2025
I know many of us have been concerned about the visitors. Now that our loonet is so big and healthy, knowing this info might help us breath a little easier!
In recent weeks, you may have noticed larger groups of loons on your local lake. At this time of year, it is not uncommon to see groups of 3, 5, 10, or even 20+ loons, especially on larger lakes. This may seem unusual, as loons are typically very territorial during the breeding season—throughout much of the summer, the resident pair on a territory will chase any extra loons out. However, larger social gatherings consisting of multiple loons become more normal from mid-July onward. These late-season social gatherings often consist of non-territorial birds (those loons that were not able to acquire or maintain control of a breeding territory during the summer) and loons that held a territory but did not succeed in hatching or raising chicks. Later in the summer, loons that have succeeded in breeding may also start to join in on the gatherings.
Why do loons switch from being territorial and aggressive towards other loons early in the breeding season to being more tolerant and social later in the summer? There are several potential explanations. Loons that do not yet have a territory of their own may join social gatherings in order to gain information about the lake they are visiting—did it produce chicks this year?—which can help them decide which territories they may be interested in trying to take over the next year. If a pair has succeeded at raising chicks and other loons land on their lake and start a social gathering, one of the pair members may join the gathering in order to distract the intruders and keep them away from their chicks. Loons that occupy nearby territories may join social gatherings on a different lake in order to attract nonbreeders to that lake, keeping the extra loons away from their own lakes and chicks. For those loons that will take part in group feeding during migration or in the winter, late-summer social gatherings can serve as good practice, priming them to work well with others when the time comes. Dr. Judy McIntyre noted that loons' hormone levels may be waning in the late summer because the time for nesting has passed, which may help to reduce their levels of aggression towards other loons and facilitate social behavior.
Photo credit: Kittie Wilson