The false killer Pseudorca crassidens, is neither a killer whale nor a whale at all, but a large species of dolphin! When it was discovered, the skull of this cetacean was determined to be very similar to that of the killer whale, Orcinus orca, which lead to its description as “false killer whale”.
False Killer Whales grow to between 15 and 17 feet long, with females growing on average 1 to 3 feet shorter than males. Their characteristic features include dark grey or black skin, with a light patch of skin on the underside of the neck below the eye. With streamlined bodies, these dolphins are powerful swimmers.
False killer whales inhabit tropical and semitropical regions around the world, usually in open ocean waters but venturing into coastal waters occasionally. Populations have been found in Hawaiian waters and the Gulf of Mexico. The Hawaiian population of False Killer Whales is classified as endangered; numbers of Hawaiian False Killer Whales have declined at a rate of 9% per year since the early 2000s. A survey conducted in 2010 estimated the size of this population of False Killer Whales to be around 1550 individuals. Unfortunately, the Hawaiian False Killer Whales are the only well studied population in United States waters.
Fisheries are the primary threat to False Killer Whales. False Killer Whales try to eat bait or fish caught on commercial fishing lines, becoming hooked or entangled leading to serious injury or death. Commercial fisheries target many of the same species False Killer Whales feed on, including tuna, billfish, wahoo, and mahi mahi. Other threats include exposure to toxic chemicals from pollution, resulting in disease or damage to the reproductive systems of False Killer Whales.
This has been On the Ocean, a program made possible by the Department of Oceanography and a production of KAMU-FM on the campus of Texas A&M University in College Station. For more information and links, please go to ocean.tamu.edu and click On the Ocean.
Script Authors: Aleck Hernandez and Cydney Sutherland
Editor: James M. Fiorendino
Contributing Professor: Dr. Lisa Campbell
Featured Image: NOAA