Researchers in the Bahamas have presented what appears to be compelling evidence of the resurgence of North America’s most endangered songbird.
Writing in the Wilson Journal of Ornithology, Todd M. Jones, Michael E. Akresh, and David I. King report that, between January and March in 2012 and from December 2012 to March 2013, they captured or sighted at least 10 Kirtland’s Warblers on tiny San Salvador Island.
Two of the birds, both male, wore colored leg bands. Each had originally been captured over 1,500 miles away, near Mack Lake, Oscoda County, Michigan — one in 2009, the other in 2006.
“Our observations of Kirtland’s Warblers are, to our knowledge, the first documented sightings and captures on San Salvador Island in over 46 years,” write the researchers.
San Salvador is located 118 miles southeast of Eleuthera, east of Nassau, where ornithologists have been studying overwintering Kirtland’s Warblers since 2002.
Birders, ornithologists, and student groups have been surveying San Salvador since 1970 but did not report the warbler, write the researchers. They suggest that earlier surveys may have focused on habitat types that aren’t preferred by the species.
“An alternative explanation for the gap in sightings of Kirtland’s Warblers on San Salvador is that the species has actually been absent from the island for the past 46 years,” Jones, Akresh, and King write. “By this logic, the numerous encounters we report could be [a] result of the species’ recent population increase and breeding range expansion into Michigan’s Upper Peninsula, Wisconsin, and Ontario.”
Counters in Michigan found 2,004 singing males during the 2013 census period, June 6-20. Observers outside Michigan tallied 21 additional males: 18 in Wisconsin and 3 in Ontario.
This article appeared in the February 2014 issue of BirdWatching Magazine.
Read the paper:
Todd M. Jones, Michael E. Akresh, and David I. King, 2013, Recent Sightings of Kirtland’s Warblers on San Salvador Island, The Bahamas, The Wilson Journal of Ornithology 125(3): pp. 637–642. Abstract.