Being less sure than Steve about what "my thing" is, or might someday be, I've maintained fairly detailed and consistent records of my counts of shorebirds on Long Island since about 1996. One never knows when one might want to be able to retrieve one's own data on shorebird numbers at Pikes Beach or Jamaica Bay in a particular date range!
Even a cursory scan of past years' data confirms that overall shorebird abundance can vary greatly in late July. As others have noted already, local weather plays a big role, but there is also the fact that the composition of the local shorebird community always changes markedly in several ways between mid July and early August (see intro from note to NYSBirds from 5 Aug 2013, copied below). Given that each component of the community might vary independently from the others in terms of abundance and timing, it shouldn't be very surprising to observe a dip in overall abundance around this time. If the adults of the early arriving species were to push through more quickly than usual, the adults of the later arriving species to build up more slowly, or juveniles to make a late or poor showing, all of which could easily happen in a given season, one would expect a dip in aggregate abundance around this time. To my eye, this summer's southbound passage of adult SB Dowitchers on Long Island was ok, or at most slightly weak, with my own max counts around 300-400, vs. more typical 700-1000 per site per day. The basic situation seems similarly decent for adult Least Sandpipers. I've also had some good counts of Semi Sandpipers at sites as widely separated as Moriches Inlet in Suffolk County and Goethals Bridge Pond on Staten Island. Conversely, my records show that various other numerically abundant species, such as Sanderling, Knot, Turnstone, Semi Plover, and BB Plover, sometimes don't build up large numbers until later in the season. What can't be explained in this way are the poor numbers of early season species at Jamaica Bay to date. On Tuesday, I checked the southern half of the East Pond carefully on the evening high tide and found just 72 Semi Sandpipers--this on the very same day I had counted 300 at Goethals Bridge Pond on a random tide. Even more shockingly to me, I saw zero Lesser Yellowlegs (another early-arriving species) at Jam Bay (I'd seen 2 in the morning at GBP--an indifferent tally but at least more than zero). For those who don't often bird coastal NY, the East Pond at Jamaica Bay has been categorically the best place in the entire region for Lesser Yellowlegs, routinely producing totals around 300 during late July. This summer, the East Pond's max to date is just 13! I think it is worth asking how much the perception of a dearth of shorebirds this summer is due to this one site's poor performance. If this is the case, why is the East Pond no longer pulling in the birds we would expect to see there? Perhaps there has been a significant change in the pond's water, sediments, and invertebrate fauna? Shai Mitra Bay Shore 5 August 2013 The latter part of July is the time for one of the year’s most striking and abrupt shifts in bird occurrence in coastal New York. As the big initial pushes of the earliest shorebird species pass beyond us, juveniles of these species, and adults of many additional species, begin arriving. Meanwhile the young of our locally breeding gulls and terns fledge, greatly augmenting the overall abundance of visible birds along the coast. Curiously, the non-breeding loafers (e.g., first-summer Common and Arctic Terns) seem to disappear just as abruptly as the local juveniles fledge, and at precisely the same time. If ever there were a year for Arctic Terns to persist past mid July, I thought this would be it, but they appear to have bailed out in just the same manner as in previous years. A much more conspicuous disappearing act is that of our adult Eastern Willets, whose vociferous throngs vanish almost completely during this interval, to be partially replaced by smaller numbers of timid local juveniles, emerging from the grass, and Western Willets, arriving from afar (hmm, this phenomenon could offer an excellent test of eBird’s ability to quantify changes in frequency and abundance of common species). ________________________________ CSI Represents NY in Nationwide State Rankings. Learn more>>><http://csitoday.com/2014/04/csi-represents-ny-in-nationwide-state-rankings/> -- 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/ --
