CASPIAN TERNS: A RARE TREAT FOR ABACO
The magnificent Caspian Tern Hydroprogne caspia is the world’s largest tern species, with an adult wingspan of about 5 feet. These birds are widely distributed throughout the world, though on Abaco and in the Bahamas generally they are classed as a very uncommon transient species, classified as T4 signifying a mere handful of reports. Ever.
However Keith Kemp, redoubtable beach monitor for piping plovers, recently saw 2 on Winding Bay beach, Abaco. Moreover he managed to photograph them in flight (see header and above image).
Keith’s are not the first Caspians to be photographed on Abaco. Bird wizard Woody Bracey managed to take one (below), which duly found its way into the ‘The Birds of Abaco‘. Sadly it could only be included in the single-bird supplement: we needed at least two images of a species for it to qualify for a spread in the main part.
Caspians have black legs, which usefully distinguish them from the tern species with orange or yellow legs. Note the heavy red / orange bill, which has a dark tip that is more noticeable in the breeding season. These large birds feed mainly on fish, and use their spectacular bills to good effect, hovering and then plunge-diving onto their prey.
Caspian terns are found on 5 continents. The transient birds that pause in the Bahamas are on their migration to the West Indies and Gulf. Or on their way back, of course.
In the late c18, a specimen bird was found on, in or beside the Caspian Sea and was promptly named after it. The distribution map above suggests they still breed in the area. How fortunate it wasn’t found by the Dead Sea…
WORRYING WIKI FACT OF THE DAY
In 2016, a nest of the Caspian tern was found in the Cape Krusenstern National Monument in northwestern Alaska, 1,000 miles further north than any previous sighting. This development was part of a general trend in Alaska of species moving to the north, a tendency ascribed to global warming.
Credits: Keith Kemp (1, 2); Dmitry Mikhirev (3); Woody Bracey (4, 7); Dick Daniels (5); J J Harrison (6); planetofbirds (range map)