Thursday, June 13, 2013

How to count birds

That title may seem to be strange but it is more of an oversimplification of a concept - let me elaborate! We request reports from our monitors and staff about our focal species and any information on other waterbirds they wish to provide. Those focal species are the Piping Plover, American Oystercatcher, Least Tern and Common Tern. It is relatively easy to count Piping Plovers since they occur in numbers often no greater than several here or there. It gets a little tricky with young birds hatching all at once on some of our busier beaches (Milford Point this year with several pairs of adults and nearly 20 chicks at times) but with some patience, caution, and experience you can accurately count them or get very close to the real number. American Oystercatchers are easy - they're bigger, brighter, louder, and in most cases, less in number.

However, it gets tricky with the terns, especially Least Terns as they tend to be more common on our monitored beaches. The best strategy for counting and their safety is to remain some distance away and use your binoculars. If you can see them all on the beach or hovering over it pick one of the groups (in the air or on the ground) and count them off left to right. Are there more than a few dozen? Then you may want to move on to counting by fives. Are there more than one hundred? Then do the same by tens.

This is how we were able to get a few counts of 540-580 Least Terns at Milford Point on various days in the last week. If you use this group counting method you will come close to what is reality. It helps if they are all flushed in the air and in one general group to do so but of course we do not want you to flush them! If you wait long enough at Milford Point you may see them all come up at once because of another bird whether it is an annoying Great Black-backed Gull or one of the local Peregrine Falcons. The latter species has "helped" us count there quite a bit this year.

Audubon Alliance for Coastal Waterbirds, Audubon Connecticut and the Connecticut Audubon Society partnering to improve conditions for coastal waterbirds in Connecticut.

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