“CHECK OUT THE WEB” (2) SEMIPALMATED SANDPIPERS ON ABACO
Having recently headlined a post for SEMIPALMATED PLOVERS with a web-related title, I’m repeating it for Abaco’s other part-webbed shorebird, the semipalmated sandpiper. Either it’s so apposite that it doesn’t need changing; or else I lack the imagination to think up something new…
This attractive little sandpiper Calidris pusilla has the partially webbed feet that give it its name. In spring and fall these ‘peeps’ are the most numerous shorebirds on Abaco but they are just passing through on their migration further south – so-called ‘transients’. Flocks of these birds may be arriving any moment now on a beach near you. The signifiers are black legs, a short, straight dark bill, and a body that is white underneath and brown /gray on top, tinged lighter on the head and neck.
SO THEY’RE EASY TO SPOT ON THE SHORELINE?
Not really, I’m afraid. This species is very easy to confuse with other small shorebirds (with which they happily mingle), especially the less common western sandpiper which has a slightly longer and downturned bill. It takes an experienced birder to tell them apart. The most reliable way – to see the feet to check for the partial webbing between the toes – is far from easy. A photograph of the bird as it picks its way across sand, tide margins or mud may be best, if you can zoom in on the feet. The webbing is just visible in both the images above and the one below.
WHERE DO SEMIPALMATED SANDPIPERS LIVE?
These are birds of the far north – Canada’s tundras and Alaska, close to water – where they breed and lay their eggs in scrapes. Rather sweetly, the male makes several prospective nests for the female to choose her favourite and furnish with grasses etc. Both adults share incubation duties. The chicks are independent almost as soon as they are hatched. Then in early fall they head many miles south to warmer places, of which Abaco is one of the most northerly, principally as a stopover for rest before continuing their journey to the coastal margins of South America. The migrating flocks may contain tens of thousands of birds. Of the many range maps around, this one from the excellent avibirds.com shows the marked contrast between the summer and winter habitats very clearly.
HOW DO THEY COMPARE IN SIZE WITH OTHER SANDPIPERS?
The SPSP is one of the smallest shorebirds, the female being slightly larger than the male. This image shows 2 of them in the company of a much larger white-rumped sandpiper (also a transient on Abaco) for comparison.
Time now to get the binoculars out (now where on earth are they?) and patrol the beach to catch the first of these little birds as they begin to arrive in considerable numbers during their fall migration.