Delphinus delphis
The short-beaked common dolphin has the classic dolphin appearance:
a streamlined, slender body with a long beak (although shorter
than that of the long-beaked common dolphin). The skin is
sleek and water resistant. The melon is more rounded melon
than the long-beaked species and meets the beak at a sharp
angle. The body lacks sweat gland; they release heat through
their flippers. The back of the body is dark grey to black,
and the belly is light grey to creamy white. An hourglass
pattern is located on the flanks where the black and white
meet. In front of this meeting place is a yellow patch, and
a grey patch behind it. A black stripe located at the lower
jaw extends across the body to the flipper. Another black
stripe extends from the eye to the beak. The beak is black
with a white tip. The dorsal fin is shaped like the classic
shark's: sickle-shaped and erect. The flippers taper to a
point. Both the flippers and dorsal fin are larger in the
short-beaked species.
The males are slightly larger than the females, with an average
length of 5-8 ft and an average weight of 160-297 lbs, making
it larger than the long-beaked. The jaws contain a total of
80-110 teeth.
Short-beaked common dolphins are the fastest of all the small
dolphins, reaching speeds of 27 mph. They communicate with
a series of high-pitched whistles and clicks. They have an
average life span of 25 years. They must surface every 2-3
minutes to breathe.
Short-beaked common dolphins are found in the offshore and
sometimes coastalwaters of most temperate and tropical seas.
They are found from British Columbia south to central Chile
on the Americana side of the Pacific. On the Americana side
of the Atlantic they are found from northeastern United States
south to Argentina. On the other side of the Atlantic they
are found from Finland south to South Africa, and on the other
side of South Africa up past Madagascar, through the Indian
Ocean and down to Oceania (Australia, New Caledonia, Papua
New Guinea, etc.) and up to Japan. They are abundant in the
Gulf of Mexico, the Persian Gulf, and the Mediterranean, Red
and Black Seas. They are never found farther north than Greenland.
They are migratory and follow fish stocks.
Short-beaked common dolphins are found in large pods, sometimes
reaching up to 10000 individuals.
Short-beaked common dolphins feed on fish such as cod, herring,
sardine, hake, pilchard and flying fish, as well as squid,
cuttlefish and crustaceans.
Sexual maturity is reached at 5-6 years of age. The mating
season is from September to December, and a single calf is
born after a gestation period of 10 months. The calf is born
tail first and the mother pushes it to the surface to take
its first breathe. Several other females protect the cow and
calf from sharks attracted by the blood released during birth.
Nursing takes place underwater. Weaning is reached after 6
months. The calves are 36 in long at birth.
Sharks and killer whales are natural predators of short-beaked
common dolphins, although short-beaked common dolphins are
often victorious in a fight against a shark. Humans pose a
huge threat to their survival. Black Sea fishermen at one
time hunted them in large numbers, and they are still being
hunted today by some. Many more are accidentally ensnared
in nets used to capture tuna.
The long-beaked common dolphin and Baird's dolphin are close
relatives of the short-beaked common dolphin.
1. Funk & Wagnall's Wildlife Encyclopedia, pp 474-475,
vol 4, 1974, BPC Pub Ltd, USA
2. "Common Dolphin" Wildlife Fact File, USA
3. www.neteng.bc.ca/~tursi/dolphins/index.htm
4. www.waterw.com/~doxymom/spotlit.htm
5. www.nsrl.ttu.edu/tmot/delpdelp.htm
6. ourworld.compuserve.com/homepages/jaap/delphin.htm
7. www.acsonline.org/factpack/common.htm
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