Wouldn’t you know it, as soon as I write about the predictability of nesting shifts (June 3), the loons pull a switch-a-roo. On the morning of June 3 the female went on holiday and left the male on the nest for a full 24 hours. Since then, they’ve pretty much reversed roles, female at night and male during the day. This is counter-intuitive when considering both “typical” loon behavior and the known nesting history of this pair.
Loons are daytime feeders because they use their vision to hunt. Females expend a lot of nutrients when producing eggs so they would be the one most in need of replenishing nutrients and body mass after mating. That’s one reason why it makes sense for the female to tend the nest during the night time. But this female must be back to full energy and weight if she’s willing to spend the best feeding time on the nest. Let’s see if she’s still willing to do the day shift when the hot weather returns!