Sunday, April 20, 2008

Cave Swallow

On this day in 1990, Vince Elia found a Cave Swallow at Bunker Pond in Cape May. At the time, it was the only East Coast record of the species north of Florida, apart from four records from Nova Scotia (Boyle et al. 1990, Connor 1991). The swallow merited a "S.A." item in American Birds, and lingered until 4 June. This bird was believed to be of the Caribbean subspecies fulva at the time, based on rump color. A Nova Scotia specimen was of this subspecies.

The Cave Swallow gives a lesson in how quickly bird distribution can change. As of early 2008, just 18 years after the first state record, there are 34 accepted NJ records of the species, and it has become almost routine in Cape May in late fall. Cave Swallow has also been seen at Sandy Hook several times, not to mention as far north as Sussex County. This suggests that, given appropriate weather conditions and birder coverage, it will ultimately be seen in every county in the state. This explosion in Cave Swallow records has been mirrored across the Northeast, since the right weather can lead to massive falls of Cave Swallows across the region (Brinkley & Lehman 2003). To sum up, "Most sightings are related to an extended period of southwesterly flow followed by the passage of a cold front and a switch in wind direction to west, northwest, or north" (Barnes et al. 2006).

The first Cave Swallow specimen from NJ came from Island Beach in 2002, and it proved to be of the southwestern subspecies pelodoma, as expected for this season (Boyle et al. 2003). A split of fulva and pelodoma has been rumored, and if it comes to pass, "Cave Swallow" identification in NJ will become even more of a headache than at present, when all the observer usually worries about is following a small agile bird in flight.

Barnes, Scott, Joe Burgiel, Vince Elia, Jennifer Hanson, Laurie Larson, & Paul Lehman. 2006. New Jersey Bird Records Committee - annual report 2006. New Jersey Birds 32:66-76.

Boyle, Bill, Joe Burgiel, Laurie Larson, & George Nixon. 2003. New Jersey Bird Records Committee - annual report, 2003. New Jersey Birds 29:46-56.

Boyle, William J., Jr., Robert O. Paxton, & David A. Cutler. 1990. The Spring Season, Hudson-Delaware Region. American Birds 44:400-406.

Brinkley, Edward S., & Paul E. Lehman. 2003. The changing seasons: Unabashed bonanza. North American Birds 57:14-21.

Connor, Jack. 1991. Season at the Point. New York: Atlantic Monthly Press.

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