Scotia Barrens – Lawrence’s Warbler?

Last evening a Red-necked Phalarope was reported at the pond at Scotia Barrens, a species that is quite uncommon in Pennsylvania. Seven of us planned on getting to Scotia Pond at day break this morning to search for the phalarope. When we arrived, Joe Verica was also present. We all searched the pond for quite a while and came up empty-handed; it seems the bird left either last evening after it was seen or at some point during the night. However, Scotia was great for migrant warblers this morning! We were able to find ten species of warbler this morning, including a very interesting find; an apparent female ‘Lawrence’s Warbler’. Lawrence’s Warbler is not a true species, but instead, is a hybrid of the Golden-winged Warbler and Blue-winged Warbler. These two species often hybridize, producing two basic phenotypes; the commonly seen ‘Brewster’s Warbler’ and the much less-often seen ‘Lawrence’s Warbler’. Most often, birds that appear to be ‘Lawrence’s Warblers’ are second-generation backcrosses. I first noticed the hybrid this morning foraging alongside a Chestnut-sided Warbler, and with some pishing, the bird came right in and perched in front of me, allowing me to get some decent photos showing how beautiful this warbler is, even as a female! As a group we were able to observe this bird on three occasions throughout the morning, and it appeared to have quite a greenish tint to the underbelly, which among other features, could rule out a first fall female Golden-winged Warbler. Without any genetic samples from this individual, its impossible to say whether it is a pure Golden-winged or if it is indeed a hybrid. Even if it is just a Golden-winged Warbler, the genetic history of that species is so altered, that is probably isn’t a pure form of the species anyway. At any rate, the bird was beautiful and I was very happy to see it this morning! Other highlights of the morning were my first Tennessee Warbler and my first Bay-breasted Warbler of the year! Here is a link to our complete species list at Scotia Pond for this morning.

Presumed female 'Lawrence's Warbler' although it may just be a first fall female Golden-winged Warbler

Presumed female 'Lawrence's Warbler' although it may just be a first fall female Golden-winged Warbler

Chestnut-sided Warbler - first fall female

Black-and-white Warbler - first fall male

American Redstart - most likely a first fall male