25 August 2012

3rd Cycle Lesser Black-backeds (Mid-Atlantic)

Below is a series of 3rd cycle Lesser Black-backeds summering on the East Coast of the United States (Delaware and New Jersey). Most have renewed at least the first five primaries with limited secondary molt. All were photographed between 04-07 August of this year, 2012.

 
 
 

The overwhelming majority of summering Lessers in the United States are 2nd and 3rd cycle individuals (full adults are actually pretty uncommon in the summer). By this time next month, adults will start to trickle in as they presumably abandon their breeding territories. The fact that adults are mostly gone during the summer season, but present in the winter, reinforces the suspicion that there is a reoccuring population of northern breeders in N.A.

3 comments:

  1. Any ideas where the full adults prefer to summer and why they might not like it here after becoming a full adult?

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  2. My current hypothesis is that the adults are somewhere north on their breeding grounds (note there are no confirmed nesting records of LBBG in the United States or Canada...the closest known breeding colonies are in southern Greenland). These sub-adults in the United States are likely members of nonbreeding clubs that have no reason to make the trek north. I'm currently writing about this as we speak.

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