Date: 7/30/20 2:36 pm From: 'Phil Brown' via NHBirds <nhbirds...> Subject: Re: [NHBirds] Barn Swallow nestling mortality question
I don't think so, Catherine, but a good thought.I think of these species mainly being an issue for other cavity-nesting species such as the ones you mentioned.
Another thought suggested was the presence of a Cowbird chick in the nest, but I don't believe this was the case, either.
On Thursday, July 30, 2020, 5:11:52 p.m. EDT, Catherine Fisher <catherineckx...> wrote:
Hi Phil,I wonder if your friend has house wrens or English sparrows breeding on the property. Both species can be very intolerant of any nesting species. At a nearby farm, they actively trap English sparrows because they were either piercing eggs or killing nestlings. I've had house wrens destroy the nests of phoebes and chickadees - both nests with eggs and those with nestlings.
On Thu, Jul 30, 2020 at 4:49 PM 'Phil Brown' via NHBirds <nhbirds...> wrote:
Sharing the observations of a friend in Unity, NH, who reports the following:
"We hadat least 3 active barn swallow nests, 2 in the barn and 1 on the porch. Iwatched the one on the porch very closely. It had 5 chicks. This week, I foundall 5 dead on the floor over the course of 3 or 4 nights. Both parents werevery active in feeding. Everything appeared normal to me, and I wasn'tsurprised that all 5 didn't make it, but to lose them all seems strange. Thenests in the barn each had loss as well. Any idea whats going on? Theporch nest had at least 1 chick that clearly had the most vigor and it wasoften leaning out over the edge. Verysad."
A few of us have been speculating about what may have been going on and have considered several possibilities (predation, starvation, drought, food contamination, parasites, etc.) but none seems a perfect fit for what was observed.
Curious to know if anyone else has noticed anything similar this summer or in the past, or might have an idea about what was going on here.
Thanks for any input.
Phil BrownHancock, NH