Pelagic Terns
Bridled Tern Sterna
anaethetus
Sooty Tern Sterna fuscata |

Bridled Terns on July 2007 BBC Extreme Shelf
Edge Pelagic by Steve Mirick. All photos on this page remain
the property of the photographer. |
Coastal Terns
Most terns in our area are seen along the coast and may be
recorded on pelagic trips either as the boat leaves the coast or
returns. Common Terns are sometimes seen on Stellwagon Bank in
large flocks. Arctic Terns famous as long distance migrators;
Arctic to Antarctica are seen also along the coast. Terns with
the gulls belong to the family Laridae. They do not drink sea water
and most return to land every night.
Pelagic Terns
Two terns that breed on Carribean Islands
or further south follow the Gulf Stream and thus may show up on
offshore trips to the continental shelf edge. They are especially
expected after strong hurricane winds.
Bridled
Tern Sterna anaethetus
Other Names
Also known as the Brown-winged Tern.
Breeds
Breeds in colonies on islands. In the Pacific in
the Hawaiian Islands, Mexico, the Galapagos, Chile. In the
Atlantic in the Bahamas, West Indies, and off the African coast.
Also in the Indian Ocean. Does not breed on the Dry Tortugas.
It is usually seen on boat trips to and from the island.
Distribution
Circumequatorial. distribution. . Adults disperse in the breeding
areas. Juveniles follow the gulf stream where a few are pushed
as far north as Nova Scotia usually by hurricane winds.
How To See
In our area take an offshore pelagic to the continental shelf
edge south of Cape Cod. Bridled Terns were recorded and
photographed on the August 2004 BBC shelf edge pelagic and on the
2007 July trip.
Behavior at Sea
The Bridled Tern likes to perch on floating debris as you can
see in the following photographs. They can also sit on the
water. Sooty Terns are reported not to sit on floating debris.
Like the Sooty Tern it does not plunge dive.
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Two Bridled Terns photographed by Bruce Larson on the
July 2007 BBC Extreme Shelf Edge Trip. A third tern was also
seen first sitting on floating debris. |

Jeremiah Trimble took these two photographs of the Bridled
Tern seen on the August 2004 Shelf Edge trip. Again
the bird was first seen sitting on a floating log. |
 |
Sooty Tern
Sterna fuscata
Breeds
The Sooty Tern breeds on the Dry Tortugas an island in the ABA
area that is easily birded in April. It also breeds in the
Hawaiian Islands, west coast of Mexico, Galapagos Islands, west
coast of Africa.
Most do not breed until the sixth to eight year having the
longest period to maturity of any of the Laridae (Harrison
1983. Carribean juveniles remain off the west coast of
Africa for several years until returning to breed.
Behavior
Does not plunge dive. Catches prey by swooping low over the
water. Rarely returns to land except for breeding.
Often circles high over the water and rarely sits on the water.
Not as likely to be sitting on floating debris.
How To See
Sooty Terns have not been seen on recent pelagic trips.
Look for them on the offshore continental shelf edge trips. You
could be the first to see one. Otherwise take a wonderful
trip to the Dry Tortugas in April.
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Adult Sooty Tern photographed on Eastern Island at
Midway Atoll by Emmalee Tarry. |
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