Feresa attenuata
The pygmy killer whale, also known as the slender blackfish
or the slender pilot whale, closely resembles both the false
killer and the melon-headed whales. The head is rounded and
the body is slender and small, with a maximum length of 8.5
ft. The maximum weight is 495 lbs. The flipper tips are rounded
and the dorsal fin is large. The jaw is underslung and the
beak is indistinguishable from the head. The top jaw contains
8-11 pairs of teeth, and the bottom jaw contains 11-13 pairs
of teeth. The backbone contains 68-71 vertebrae, unlike the
false killer whale, which has only 50.
The colouring is a dark black, blue-black, or grey-brown.
The lips and often the entire lower jaw are white, creating
a sort of "goatee." The beak and genital area is
also often white. A dark stripe stretching from the top of
the head and widening at the dorsal region forms the dorsal
cape. A light grey patch extends from the throat to the vent
area.
It is believed that pygmy killer whales can extrude their
eyes from their sockets so that they can look behind themselves.
Pygmy killer whales can be found in tropical and subtropical
waters worldwide. They prefer deep waters away from coast
lines. They are found in the Gulf of Mexico, the Mediterranean
Sea, the Indian Ocean, the Southeastern Atlantic Ocean, and
near Sri Lanka and Lesser Antilles. They are though to live
year-round in at least the Gulf of Mexico.
Pygmy killer whales feed upon cephalopods (squid) and large
fish, such as tuna. They are thought to kill and eat other
dolphins as well.
Pygmy killer whales deserve the name "killer" much
more than their counterpart the killer whale. They are highly
aggressive and cannot be handled. One specimen was captured
off Hawaii in 1963 and sent to Sea Life Park. The day after
its capture it tried to attack a man checking the water input.
Ten days later it was placed in the same tank as two pilot
whales. The youngest of the two was later found dead. The
cause of death: a sharp blow to the cranium by the head of
the pygmy killer whale.
Very little is known about their breeding habits. The males
and females become sexually mature when they reach the length
of 7 ft. The calves are 32 in long at birth.
Pygmy killer whales are sometimes fished by Japanese fishermen.
300-800 are captured each year by Sri Lankans. Many others
are killed worldwide by becoming entangled in fishing nets
or trapped in purse seines used to trap tuna.
The pygmy killer whale was first made known to science after
the discovery of two skulls of a previously unknown species.
John Gray of the British Museum examined them from 1827-1875
and named them Feresa attenuata. It wasn't until after 1950,
however, that actual specimens were found. Today they are
rarely seen in the wild, and are mostly known by strandings
and net entanglements. They have been seen in pods ranging
in size from 25-50. They are rather acrobatic and will bow-ride
with rough-toothed dolphins.
The pygmy killer whale is a species of dolphin and is in the
same subfamily as the melon-headed whale, false killer whale,
killer whale, long-finned pilot whale and short-finned pilot
whale.
1. library.advanced.org/17963/subfamily-Globicephalinae.html#attenuata
2. hyperion.advanced.org12605/pygkill.htm
3. www.nsrl.ttu.edu/tmot/fereatte.htm
4. www.geocities.com/RainForest/Canopy/1599/pkiller.htm
5. elfi.com/csipygmykiller.htm
6. www.upstarts.net.au/site/ideas/whales/whalesspecies/ pygmykillerwhale.html
7. www.gomr.mns.gov/homepg/regulate/environ/marmam/ pygmy.html
8. seahorse.ims.usm.edu/~musweb/feratten.htm
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