[Tweeters] possible Barn x Tree Swallow

[Steve Hampton]

Today south of Chimicum, Jefferson County, I photographed an
unusual swallow.
Photo at *https://ebird.org/checklist/S105328086
<https://ebird.org/checklist/S105328086>*.

The upperparts were dark blue, similar to Barn Swallow.

It differed from a typical Barn Swallow in the following ways:
- all the red/orange parts (forehead, throat, underparts, underwings) were
rather bright white.
- the forked tail was on the short side, lacking the longest outer
rectrices.

Also notable is that it was with Tree and Violet-green Swallows, and
represents the first Barn Swallow of the season in the county; no other
Barn Swallows were present.

The white in the throat and forehead rules out Eurasian Barn Swallow, as
well as the even more similar White-throated Swallow (from southern Africa
and not that migratory, thus virtually impossible).

Dessi Sieburth suggested Barn x Tree Swallow. I can find no reference of
such a beast, except for this intriguing post from Newfoundland in 2015,
which is a fairly similar bird:
https://retiringwithlisadeleon.blogspot.com/2015/05/possible-hybrid-swallow.html
.

The Birds of the World account says:
*Barn Swallow*
*Hirundo rustica* is known to hybridize with both *Petrochelidon pyrrhonota*,
the Cliff Swallow, and *P. fulva*, the Cave Swallow, with records in
western North America from Washington south to California, western
Nebraska, Arizona and Texas, and in eastern North America from Pennsylvania
south and west to Oklahoma and Texas. In the Old World, the Barn Swallow
has hybridized with *Delichon urbicum*, the Common House-Martin, and *Cecropis
daurica*, the Red-rumped Swallow.

*Tree Swallow*
A mixed pair *T. bicolor* and *T. thalassina* [Violet-green Swallow] nested
in Illinois, far east of the latter species' normal geographic range, but
failed to raise young (Johnson and Moskoff 1995). Another mixed pair of
these two species has been reported at a natural nest in Wyoming (S.
Johnson pers. comm.), but it is not clear whether that pair produced
offspring. Otherwise, the sole hybrid reported is a *T. bicolor* ×
*Petrochelidon
pyrrhonota* (the Cliff Swallow) collected in Massachusetts (Chapman 1902).

The only other option would be a Barn Swallow with a pigment deficiency,
though that doesn't account for the short tail.


-- 
Steve Hampton
Port Townsend, WA  (qatáy)
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