Hi Tweets,

Michael G. Shepard, in speaking of warbler hybridism, writes:

>I have a strong suspicion that a substantial proportion of the birds
[Black-throated >Gray Dendroica nigriscens and Townsend's Warblers D.
townsendi] may be
>hybrids. We are now catching hybrids annually at the Rocky Point
>Migration Monitoring Station at the southern tip of Vancouver Island. A
>few are distinctly intermediates, while most are Black-throated Grays with
>a few Townsend's characteristics such as greenish backs or yellow flecks on
>the breast.

I'd be very surprised if the hybrid-zone between these two was restricted to
Vancouver Island but wasn't also on the mainland. Also, is there an actual
increase in the number of hybrids of Hermit Warbler D. occidentalis and
Townsend's showing up in the Canadian Southwest? What are the chances of a
*pure* Hermit's?

Incidentally, I was in on the sighting of the first Hermit Warbler for
Vancouver BC at Queen's Park during a big fallout there in the early 1990's.
Even though the bird clearly had a greenish back color identical to
townsendi, conspicuous coarse black streaking all down one side of its
breast to the lower flank area and fine black streaking down the other, and
a very pale suffusion of yellow on the upper breast, it was still accepted
by the rest of the Vancouver Rare Birds Committee as a pure Hermit Warbler,
and is in the official record as such, though these features *clearly*
indicate a hybrid parentage.

>Is anyone else seeing or catching these types of hybrids?

Michael, try going out in the forest and singing 'Buddy, Can You Spare a
Gene?' and see what their DNA looks like. I understand the
Hermit/Townsend's/Black-throated Gray complex is gonna be a real headache.
Can anyone fill us in on the latest?

Michael Price
Vancouver BC Canada
mprice at mindlink.net