Banding Lab Sees Seasonal shift to Late migrants

On October 9, Manomet’s banding lab caught a 20.4-gram Blackpoll Warbler on the brink of migration. These warblers, which typically weigh only 10 grams, double their weight every year to prepare for their long distance journey back to their wintering ground in the Amazon Basin.  

 

The arrival of late fall migrants like the Blackpoll Warbler indicates the transition from early migrant warblers and Gray Catbirds to later migrants like Ruby-crowned Kinglets, Brown Creepers, Myrtle Warblers and White-throated Sparrows.

 

 “We see this switch in species every year during this time at Manomet,” said Banding Director Trevor Lloyd-Evans. “The only unusual trend this fall is that we have yet to have any massive migration days. There have been only eight days this season which we have handled over 75 birds, and that is uncharacteristically low.”

 

The lack of large migration days can be attributed to many things, including unfavorable winds and weather, but the banders have still handled over 2,000 birds, which is in line with the lab’s 10 year average.

 

 

While the overall trend in fall arrival times has been consistent with Manomet’s 45 year landbird migration dataset, a Yellow-bellied Flycatcher was caught on October 2, which is uncharacteristically late as the species usually feeds on flying insects, which begin to tail off at the end of September.

 

Some other unusual captures included two Gray-cheeked Thrushes, an Orange-crowned Warbler and 27 Myrtle Warblers that were caught in one day (October 14).

 

While it’s not surprising that Gray Catbirds have been the most common bird this season, it is surprising that Red-eyed Vireos have been the second most common species handled, with 56 new captures recorded so far.

 

Last month, the banders joined banders from past seasons for Bird-a-Thon, an annual event where teams count the number of birds they see in 48 hours and recruit supporters to pledge money for each species sighted. The funds raised help support Manomet’s landbird banding and education programs. The Manomet Intern team led this year’s competition with 209 species.