Interesting, how things have changed. The 1947 version of the Peterson Field Guide to Birds states that there were only a handful of records of Lesser Black-backed Gull in North America - and no specimens.
Has there been any established breeding population in North America yet? Rich Guthrie New Baltimore The Greene County New York On Tue, Sep 15, 2015 at 8:16 PM, Shaibal Mitra <[email protected]> wrote: > After speaking this morning with Mike Cooper about our recent impressions > of Lesser Black-backed Gulls on Long Island, I thought it might be best to > expand the conversation. > > The basic question that Mike raised (I think I'm re-stating it correctly) > is whether recent reports of large numbers of LBBGs along the south shore > of western LI represent southbound migrants or birds continuing from summer > aggregations. > > My impression is that both factors are contributing to the pool of birds > present recently, and that this combination itself might be somewhat > unusual. > > In recent years, increasingly large numbers of immature LBBGs have > summered on LI, often in fairly discrete aggregations around various ocean > inlets, with Jones Inlet consistently hosting the largest counts. Even so, > it can be difficult to find the birds involved in these flocks from day to > day and week to week throughout the summer, probably because they generally > forage far offshore (note the consistent over-representation of this > species among large gulls on pelagics, as vividly illustrated by Sean > Sime's account of the 31 Aug trip to Hudson Canyon), and because few people > work methodically and consistently at trying to find and count them. In the > past, these loafing flocks seem to have broken up (perhaps moving south) > just ahead of the arrival of migrant adult LBBGs from the far north, in > early to mid September, and well ahead of the arrival of juveniles in late > September to early October. > > The largest count on LI this summer that I am aware of was 33, counted by > Pat Lindsay, Billy Hanley, and me at Jones Beach West End, on 4 Sep, during > a favorable confluence of hide tide and strong east winds. This aggregation > consisted of 16 second calendar-year (SY), 12 third calendar-year (TY), and > 5 fourth calendar-year (4Y)--with the acknowledged possibility of some > mis-assignment between SY and TY, and between TY and 4Y. It surely > overlapped in content the count from a month earlier at the same site of 26 > immatures of various ages by Shawn and Mary Beth Billerman. The complete > absence of full adults on 4 Sep makes me question whether southbound > migrants were involved at all, but it is of course possible that young > birds summering to our north, for instance on Nantucket, might be sliding > down the coast and mixing with our summering birds. > > Jane Ross and Magda Binion saw the first full adult I am aware of this > fall at Sagaponack on 5 Sep, a rather typical arrival date for this age > class. My group missed that bird, but we did see an SY bird and SY/TY bird > at Sagg on 5 Sep. Later that day, Pete Morris, Taylor Sturm and I saw an > exceptionally early fresh juvenile at Montauk Pt (1 Oct is a more typical > arrival date). Pat Lindsay and I saw our first full adult of the fall at > Cupsogue on 7 Sep; indicative of the complexity of the situation, a TY type > was present with it. > > The recent, expected, arrival of full adults, as well as the less > expected, extremely early, arrival of a juvenile, prove that migration has > commenced. What we don't understand at present is the timing of movement of > the SY and TY birds that have become so prevalent during summer along the > mid-Atlantic coast. > > Specific questions I would pose to this highly informed forum are the > following: > > 1. My records indicate a very abrupt arrival of full adults starting > around 5 Sep, with almost no convincing earlier exceptions. Are others > aware of such exceptions? > > 2. Similarly, juveniles normally appear to arrive after about 23 Sep; the > Montauk juvenile of 5 Sep 15 is an outlier, but perhaps others are aware of > other convincing early records. Are these outliers perhaps attributable to > predicted but as yet undiscovered North American breeders? > > 3. Really large counts of SY and TY birds (>20) seem to be restricted to > the summer months, sometimes persisting into early September (as on 4 Sep > 15), but later on, I've encountered these younger immatures only in > markedly smaller numbers (single digits). After late October, these non-juv > immatures appear to be actually rare on LI. Does anyone have data or a > strong impression about the timing of movements of these one and two > year-old birds? > > Shai Mitra > Bay Shore > > ________________________________ > CSI Tops MONEY magazine’s Best Colleges list for 2015-2016>< > http://csitoday.com/2015/07/csi-tops-money-magazines-best-colleges-list-for-2015-2016/ > > > > -- > > NYSbirds-L List Info: > http://www.NortheastBirding.com/NYSbirdsWELCOME > http://www.NortheastBirding.com/NYSbirdsRULES > http://www.NortheastBirding.com/NYSbirdsSubscribeConfigurationLeave.htm > > ARCHIVES: > 1) http://www.mail-archive.com/[email protected]/maillist.html > 2) http://www.surfbirds.com/birdingmail/Group/NYSBirds-L > 3) http://birdingonthe.net/mailinglists/NYSB.html > > Please submit your observations to eBird: > http://ebird.org/content/ebird/ > > -- -- Richard Guthrie -- NYSbirds-L List Info: http://www.NortheastBirding.com/NYSbirdsWELCOME http://www.NortheastBirding.com/NYSbirdsRULES http://www.NortheastBirding.com/NYSbirdsSubscribeConfigurationLeave.htm ARCHIVES: 1) http://www.mail-archive.com/[email protected]/maillist.html 2) http://www.surfbirds.com/birdingmail/Group/NYSBirds-L 3) http://birdingonthe.net/mailinglists/NYSB.html Please submit your observations to eBird: http://ebird.org/content/ebird/ --
