[Tweeters] How Late Do Barn Swallows Fledge?

[Tom Benedict]

I saw a Barn Swallow family of 5 fledglings and 2 parents today, Sep 3, 2023 in Port Ludlow, WA. I was surprised to see fledglings this late in the summer. I found this Washington Breeding Phenologies <https://www.burkemuseum.org/sites/default/files/2019-07/BreedingPhenologyProject_sm.pdf> document which shows that egg laying peaks in May and June, followed by a secondary peak in late July and early August, likely representing a second brood. Given that incubation can take 12-17 days and fledging another 19-24 days, the eggs for these young birds were likely laid in the last week of July. So this family is well within the normal range.

I guess there is sufficient food (insects) around in September to support these youngsters, but they must be starting to think about migration soon.

Tom Benedict
Seahurst, WA
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