Common Dolphin (Delphinus delphis)
Common dolphins are easily recognised
by the hourglass pattern and tan or yellowish patch on each
side, although they can sometimes be confused with striped
dolphins. They have a dark cape ranging from black to brown
with a v-shape under the dorsal fin. They also have a white
underside with occasional yellow streaks and a white tail
stock. Their flukes are dark on both sides, and their dorsal
fins range from curved to triangular and can be black, greyish
white or somewhere in-between. They vary so much that people
have suggested there are a number of different species.
Only two distinct forms are recognised; the long-beaked
and short-beaked. There are only subtle differences between
the sexes and males and females are difficult to tell apart.
Streamlined body, long slender beak, single blowhole, pointed
flippers, hourglass pattern on sides, dark flippers, tail
and fin, dark cape (area of the back around the dorsal fin),
fast active swimmer.
When they are born, common dolphins are about 80cm long.
They grow to between 1.7 and 2.4 metres in length.
Common dolphins feed on small fish as well as squid and
octopus. Small fish include young herring, pilchard, anchovies,
nocturnal hake, sardines, small bonito. Individual dolphins
eat up to 18 to 20 pounds of fish per day. These feeding
forays can last up to an hour. During these, each dolphin
rushes to the centre of the school the group has been pursuing
and tries to seize as many fish as possible, which it swallows
whole. Common dolphins have also been known to dive below
schools and drive them to the surface. They push their prey
completely out of the water and catch them in midair.