Word of the Day – Thursday, April 19th
birds related to gulls but characteristically smaller and having a
Terns are seabirds in the family Sternidae, previously considered a subfamily Sterninae of the gull family Laridae. They are less closely related to the waders, auks and skimmers. They have a worldwide distribution.
terns belong to the large genus Sterna,
with the other genera being small, though some authorities split
the genus Sterna
into several smaller genera.
terns breeding in temperate zones are long-distance migrants, and
the Arctic Tern probably sees more daylight than any other
creature, since it migrates from its northern breeding grounds to
Antarctic waters. One Arctic Tern, ringed as a chick (not yet able
to fly) on the Farne Islands off the Northumberland coast in
eastern Britain in summer 1982, reached Melbourne, Australia in
October 1982, a sea journey of over 22,000 km (14,000 miles) in
just three months from fledging - an average of over 240 km per
day, and one of the longest journeys ever recorded for a bird.
are in general medium to large birds, typically with grey or white
plumage, often with black markings on the head. They have longish
bills and webbed feet. They are lighter bodied and more
streamlined than gulls, and look elegant in flight with long tails
and long narrow wings. Terns in the genus Sterna
have deeply forked tails, those in Chlidonias
shallowly forked tails, while the noddies
have unusual 'notched wedge' shaped tails, the longest tail
feathers being the middle-outer, not the central nor the
and the noddies) hunt fish by diving, often hovering first, but
the marsh terns (Chlidonias)
pick insects of the surface of fresh water. Terns only glide
infrequently; a few species, notably Sooty Tern, will soar high
above the sea. Apart from bathing, they only rarely swim, despite
having webbed feet.
Terns are generally long-lived birds, with several species now known to live in excess of 25-30 years.