An important piece of information to consider when recalling the 18 June shearwater flight is food availability within offshore LI waters. Many birds were already here prior to the 18 June flight and the moderate coastal depression is what likely drove a significant number of these individuals into the beaches. I suspect the same would likely happen now if we were to experience another weather event with moderate to strong southeast winds because the huge numbers of shearwaters continue to feed off Long Island out to 30 nautical miles and beyond. Casual observations from before and after the large inshore shearwater flight on 18 June indicate improved abundance and quality of food relative to recent years. I've spoken with a handful of offshore fishermen who, without being provoked and unaware of the 18 June flight, referenced "a lot more birds than usual." This coincided with "a lot more bait than usual," mostly sand eels. There have also been lots of baleen whales, presumably attracted to this food. Some personal shearwater observations from three combined combined offshore outings on 4 June, 22 June, and 5 July include the following. -463 Cory's Shearwater -703 Great Shearwater -535 Cory's/Great Shearwater -142 Sooty Shearwater -8 Manx Shearwater These Cory's and Great Shearwater totals seem larger than normal and of course provide only a narrow snapshot of what offshore NY looks like. On all 3 outings, rafts of Cory's, Great and Sooty Shearwaters were found feeding and sitting on the surface as close as 2.5 nm from the beach, which is why I wouldn't have been surprised if another moderate wind/weather event produced big seawatch numbers of large shearwaters. Along with these bird sightings, we've been detecting masses of bait from 8 nm out to approx. 30 nm and further south at the continental shelf break. And I'm still getting text messages from offshore fishermen finding huge numbers of birds out to 30 nm. Just like our terrestrial migrants, seabirds are also faced with rapidly changing environmental conditions along their migratory pathway, it's just more difficult for land-based observers to monitor. So perhaps several hundred (probably more like thousand) dead Great Shearwaters, isn't so significant in an area where they regularly pass through and are currently congregating in mass. After all, their estimated population is in the millions. The fact that Cory's are also present in large numbers but to my knowledge few, if any, Cory's specimens were recovered is interesting. One possibility, as suggested by others, is that Great Shearwaters have had a tougher time finding food near their departure grounds in the South Atlantic and were thus weaker (or more prone to disease) when they arrived in our waters. Cory's Shearwaters have a different point of origin and shorter migration. Best, Derek Rogers Sayville
> On Jul 16, 2017, at 10:56 AM, Hugh McGuinness <hdmcguinn...@gmail.com> wrote: > > To play Devil's Advocate for a second: Great Shearwater is regular from > mid-May to late August off Suffolk County, so their occurrence in Nassau is > not really that surprising, and might be explained by something like the > improved quality of feeding offshore from Nassau, for which there is some > recent evidence. I agree that the shearwater kill requires an explanation, > but I remain unconvinced that the birds were significantly off course. > > Hugh > >> On Sun, Jul 16, 2017 at 8:24 AM, Shaibal Mitra <shaibal.mi...@csi.cuny.edu> >> wrote: >> Hi Dick and all, >> >> I think it's fair to say that the multi-hundreds of Great Shearwaters >> observed from the Nassau County shoreline on 18 June were off course. The >> species is entirely absent from this area for years at a time (I'd never >> previously seen even one from shore in Nassau in over twenty years), and the >> sum total of records over all time is vastly lower the numbers seen in just >> a few hours. Thus, their extreme concentration in a small area where they >> are ordinarily completely absent requires explanation. The fact that they >> were starving explains why many birds died, but alone it doesn't account for >> why they were bunched up in the New York Bight, rather than dispersing over >> a broader area of nearby waters they typically inhabit. All else equal, in >> the absence of food, one would expect widely foraging pelagic birds either >> to spread out randomly, or possibly to orient directly for traditionally >> productive areas, such as Block Canyon, Georges Bank, etc.--if they could. >> Food shortage alone doesn't account for the unprecedented densities inshore >> in the New York Bight, unless they were actively seeking food in this >> unusual area, with seems very unlikely. I think they were starving, tried to >> keep moving, and wound up following a path of least resistance that brought >> them to where we encountered them. >> >> Shai Mitra >> Bay Shore >> ________________________________________ >> From: bounce-121659418-3714...@list.cornell.edu >> [bounce-121659418-3714...@list.cornell.edu] on behalf of Richard Veit >> [rrvei...@gmail.com] >> Sent: Saturday, July 15, 2017 3:31 PM >> To: Ardith Bondi >> Cc: NYSBIRDS; eBirdsnyc >> Subject: Re: [nysbirds-l] Fwd: A Mystery of Seabirds, Blown Off Course and >> Starving - The New York Times >> >> i don't see any evidence of birds being "blown off course". Starving, yes, >> and this seems likely due to shortage or lack of food, perhaps related to >> changing climate. But wrecks of great shearwaters of roughly similar >> magnitude have been occurring episodically for years, perhaps moreso in >> Massachusetts than on long island >> >> On Sat, Jul 15, 2017 at 12:12 PM, Ardith Bondi >> <ard...@earthlink.net<mailto:ard...@earthlink.net>> wrote: >> -- >> >> NYSbirds-L List Info: >> http://www.NortheastBirding.com/NYSbirdsWELCOME.htm >> http://www.NortheastBirding.com/NYSbirdsRULES.htm >> http://www.NortheastBirding.com/NYSbirdsSubscribeConfigurationLeave.htm >> >> ARCHIVES: >> 1) http://www.mail-archive.com/nysbirds-l@cornell.edu/maillist.html >> 2) http://www.surfbirds.com/birdingmail/Group/NYSBirds-L >> 3) http://birding.aba.org/maillist/NY01 >> >> Please submit your observations to eBird: >> http://ebird.org/content/ebird/ >> >> -- > > > > -- > Hugh McGuinness > Washington, D.C. > -- > NYSbirds-L List Info: > Welcome and Basics > Rules and Information > Subscribe, Configuration and Leave > Archives: > The Mail Archive > Surfbirds > ABA > Please submit your observations to eBird! > -- -- NYSbirds-L List Info: http://www.NortheastBirding.com/NYSbirdsWELCOME.htm http://www.NortheastBirding.com/NYSbirdsRULES.htm http://www.NortheastBirding.com/NYSbirdsSubscribeConfigurationLeave.htm ARCHIVES: 1) http://www.mail-archive.com/nysbirds-l@cornell.edu/maillist.html 2) http://www.surfbirds.com/birdingmail/Group/NYSBirds-L 3) http://birding.aba.org/maillist/NY01 Please submit your observations to eBird: http://ebird.org/content/ebird/ --
