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Message: <blockquote data-quote="Mark B Bartosik" data-source="post: 3214507" data-attributes="member: 18843">On May 7, 2015 I encountered a huge migrating Common-Black Tern flock (or rather several huge flocks) resting along about 1.5 mile long stretch of the beach at southern part of the Bolivar Peninsula known as Bolivar Flats. I estimated (very coarse estimate) number of COTE to be about 20- 30 thousands so I report the low number. I just divided that number by twenty to get even more coarse number of BLTEs (one thousand) that should be a very low estimate as well (most BLTE stayed well concealed between much bigger COTE when resting). I did not check the beach up north from Bolivar Flats so the numbers of both species resting on the Peninsula on that day could be significantly larger. It is interesting from the point of migration routes and dates COTE takes during the spring migration. The eBird database for Texas shows these COTE records (all recorded years): spring migration in April – 800 and in May – 200. Largest number was recorded during fall migration, beginning of October – 5000.On that day (May 7) I left COTE-BLTE flocks resting on the beach right before sundown (note: there was almost no human disturbance on that evening). Next day (May 8), afternoon, I found only about 1500 COTE resting (2 large flocks) and only a few dozen BLTE. After somebody drove intentionally into resting birds the number of returning birds started to shrink. After 7 PM were only a few dozen COTE on the beach and flats.  I did not have time to check this place during the next day. On May 8 I found (finally, after trying to check so many birds) one banded individual. Unfortunately I only got partial number 1272(?4) see photo – perhaps someone can make at least one more digit.<a href="http://www.pbase.com/mbb/image/160005656" target="_blank">http://www.pbase.com/mbb/image/160005656</a>Even if it is not possible to pin-point an individual perhaps it will be possible to find the location where this COTE was banded to have a possible idea where it might be going back. BTW from the published papers I understand that the inland breeding populations are migrating along Atlantic coast. Is that mean that flock that huge is going to keep moving along the Gulf coast to Florida and then up north?For several years now I suspect that Galveston Bay area (and especially Bolivar Peninsula) is a very important entry place for migrating terns (have this recorded quite well for the Least Tern). My question is why so huge COTE flocks are showing up here and not just migrating along Florida Atlantic shore line if they indeed don’t travel across the land to northern breeding grounds in Great Lakes. Perhaps it is a ‘refueling’ stop (if so than it is even more important to protect this area now and in the future) but I would assume that there is plenty of food in Florida waters as well. I see no support in eBird data for Pacific flocks crossing Central America (no inland records but maybe not detected due to a few observers there) and records along shore lines on both sides are rather sparse as well. Answers to all these questions are just an interesting puzzle to me (so any comment is appreciate) but they might be important to these who are working on COTE migration details.Supporting materialVideo<a href="http://youtu.be/tHOYp-NBJEc" target="_blank">http://youtu.be/tHOYp-NBJEc</a>Photos (Note: some photos were taken with wide angle lens (so perspective was severely distorted) – in reality the field occupied by resting terns was about 10 times as long as it was wide (length of the front row). Also large part of flock (in background) remained to stay on the ground (did not take off).<a href="http://www.pbase.com/mbb/20_thousands_common_tern_migrating_flock__texas" target="_blank">http://www.pbase.com/mbb/20_thousands_common_tern_migrating_flock__texas</a>Cheers,Mark</blockquote>

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