Monday, June 9, 2008

Delaware Water Gap, June 7th

In a slightly insane move I ignored the prospects of getting fried in 90+ degree heat and drove to the Delaware Water Gap NRA on Sunday to look for breeding warblers.

Van Ness Rd, near Layton, has been in recent years a pretty reliable spot for Golden-winged Warbler, including a male that sings a "Blue-winged" song, albeit with somewhat of a flourish. Visually the bird looks like a pure Golden-winged. However I was reading a paper from 1997 by Frank Gill (Evolution, Vol. 51, No. 2, pp. 519-525) that indicated that gene flow from Blue-winged to Golden-winged was strictly one way and that Blue-winged supplanted Golden-winged within 50 years. The cheery title was "Local Cytonuclear Extinction of the Golden-Winged Warbler".

If that wasn't rough enough on Golden-winged, the habitat along Van Ness Rd has been going through rapid succession, possibly aided and abetted by non-native species like multiflora rose. So, as you might have guess, there were no Golden-winged Warblers this year along Van Ness Rd, although that same weekend a "Lawrence's" Warbler (Golden-winged X Blue-winged) was reported singing a few miles to the north. There were plenty of Blue-winged Warblers, along with Chestnut-sided, Yellow, Prairie Warblers, Common Yellowthroat, Scarlet Tanager and Eastern Towhee. Still a good place but the best area for Golden-winged is now Sterling Forest over the border in NY where they still hang on.

After finishing up at Van Ness I took a run into Stokes State Forest over the other side of Rt. 206. I stopped at the bridge over the Flatbrook River (Crigger Rd). At this parking lot, where the road becomes one-way, it was less productive than usual. I had heard Blackburnian Warbler and Least Flycatcher on the way up Grau Rd, but they weren't here where I'd seen them in previous years (in 2007 I watched a Blackburnian male bathe at the water standpipe here). However following the trail down the Flatbrook from the bridge I did hear Blackburnian and Black-throated Green in the dense pines, along with the usual Acadian Flycatcher and as a bonus a single tame Hermit Thrush. Based on the range map from the Birds of North America Online this would be the southerly limit of breeding for Hermit Thrush in the more coastal areas around here.

Going back along Crigger Rd towards High Point State Park, and after shedding two noisy Harleys that were tailing me, it wasn't all that difficult to find Cerulean Warbler singing along the road. Their favorite spot seems to shift from year to year. Also here was Yellow-throated Vireo. After turning right (east) onto Deckertown Pike I cut north along Sawmill Rd into High Point State Park. Here again, Least Flycatcher, Cerulean Warbler and Yellow-throated Vireo were audible along the road. There was abundant American Redstarts on these higher elevations, and Ovenbirds were heard throughout.

Because the temperature was rising rapidly into the 90's I didn't chase every single bird song or go chasing after northern NJ highland specialties like Yellow-bellied Sapsucker, so I retreated out of High Point and Stokes SF back to Rt. 206 and returned home.

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