Date: 9/6/18 9:05 pm From: Josh <opihi...> Subject: Re: [MASSBIRD] more thoughts about Barn Swallow nest sites
With all of the interest in Barn Swallows lately, I should share that the Hampshire BIrd Club’s first meeting of the fall is coming up soon, September 17, a week from Monday, and the topic will be: Barn Swallows!
I can’t say that I’ve ever seen a Barn Swallow nesting on a natural substrate. However, I think that Purple Martins and perhaps Chimney Swifts could give them a run for their money in the dependence-on-artificial-nests department. Chimney Swifts historically nested in hollow trees, but Mass Audubon’s second breeding bird atlas noted that were unable to confirm even a single pair of swifts nesting in a natural site anywhere in the state during the 5-year project, and I think this is fairly typical of most of their range. I’ve read that Purple Martins tend to be more solitary and more prone to nesting in natural cavities toward the western end of their range, but in the east, where they are more colonial, they are using just about 100% artificial nest sites.
> On Sep 6, 2018, at 7:16 PM, Ian Nisbet <icnisbet...> wrote:
> About 40 years ago, I quizzed many of my colleagues (in Europe as well as in North America), asking whether they had ever seen a Barn Swallow nest in a natural site. None of them answered Yes to that question. The account of the Barn Swallow in the Birds of North America (1999) says that the species originally (pre-humans) nested primarily in caves, but has "almost completely converted" to nesting in artificial sites. It cited a 1986 review paper which stated that since the 1960s, the only records of nesting in natural sites in eastern North America had been from West Virginia, New York, and the Canadian Maritimes, and the only place where they continued to nest in natural sites was in the Channel Islands off California. I think that the Barn Swallow is more dependent on artificial sites than any other species in North America: it is easy to find nests of Tree Swallows, House Sparrows and Starlings, for example, in natural sites. Has any Massbirder seen a Barn Swallow nest in a natural site?
> The BNA account mentioned associations of Barn Swallows with pastures and grazing animals, but the close association with cattle has been reported primarily in Europe.
> On 9/6/2018 4:52 PM, Ian Nisbet wrote:
>> In many parts of the northern hemisphere, Barn Swallows are closely associated with cattle, and declines in Barn Swallow populations have been linked to declines in numbers of dairy farms where cows graze outdoors. My guess is that as suburban development encroaches on dairy farms in New England, Barn Swallows will continue to decline whatever we do to preserve nesting sites.
>> Ian Nisbet
>> North Falmouth