False killer whales are large members of the dolphin family. Females reach lengths of 15 feet (4.5 m), while males are almost 20 feet (6 m). In adulthood, false killer whales can weigh approximately 1,500 pounds (700 kg).
They have a small conical head without a beak. Their dorsal fin is tall and their flippers (pectoral fins) have a distinctive hump or bulge in the middle of the front edge. False killer whales have dark coloration except for some lighter patches near the throat and middle chest. Their body shape is more slender than other large delphinids.
False killer whales’ breeding season lasts several months. Gestation periods range from 14 to 16 months and lactation occurs for one and a half to two years. False killer whales have low reproduction rates with calving intervals of approximately seven years. Maturity occurs at around 12 years of age and maximum longevity is 63 years.
These whales are gregarious and form strong social bonds. They are usually found in groups of ten to twenty that belong to much larger groups of up to 40 individuals in Hawai’i and 100 individuals elsewhere. They are known to “strand” in large groups as well. False killer whales are also found with other cetaceans, most notably bottlenose dolphins. To increase success of finding prey, these whales travel in a broad band that can be up to several miles wide.
Food sharing has been documented between individual false killer whales. They feed during the day and at night on fishes and cephalopods, and they are known to attack smaller dolphins that are involved in the tuna purse-seine fishery in the Pacific Ocean.
ESA Endangered – Main Hawaiian Islands Insular
MMPA Depleted – Main Hawaiian Islands Insular
MMPA – All false killer whales, like all marine mammals, are protected under the MMPA.
CITES Appendix II – throughout its range
|about 1,500 pounds (700 kg)|
|females: 15 feet (4.5 m)
males: 20 feet (6 m)
|dark coloration except for some lighter patches near the throat and middle chest|
|about 60 years|
|fishes and cephalopods|
|they form strong social bonds, usually found in groups of 10-20; they are known to “strand”in large groups as well|
RELATIVE SPECIES: Killer whale, pygmy killer whale, melon-headed whale.
NEIGHBORING SPECIES: Pygmy killer whale, melon-headed whale. Most other dolphins
THREATS: They are hunted when they interfere with fishing.
DIET: Squid and fish such as mahi mahi and yellowfin tuna.
MANNER OF FEEDING: Tear the flesh off of the fish. Wont eat bones or tails. Are known to take fish off of a fishing line.
BEHAVIOR: Lives in pods of 10-20 that may be a part of a much larger pod. Very active at the surface. Likes to bow-ride. Can be seen with bottlenose dolphins. Very social. Very defensive and have attacked larger whales, such as pilot whales.
REPRODUCTION: Gestation is 14-16 months. Females have a calf every 7 years. Calves are nursed for 1-2 years.
LIFE SPAN: 63 years
They prefer tropical to temperate waters that are deeper than 3,300 feet (1000 m).
False killer whales occur in the U.S. in Hawaii, along the entire West Coast, and from the Mid-Atlantic coastal states south. The species can also be found in all tropical and temperate oceans worldwide.
The current estimates for the Hawaiian/Pacific Islands stock and the Northern Gulf of Mexico stocks can be found in the latest marine mammal stock assessment reports.
- bycatch and other fishery interactions, such as the Hawaii Longline fishery and bottomfish fishery off the Northwestern Hawaiian Islands
- hunting in Indonesia, Japan, and the West Indies
To reduce bycatch in longline fisheries in Hawaii, we established a Take Reduction Team in January 2010. In November 2012, we published a final Take Reduction Plan, based on the Team’s recommendations.
In 2010, we reviewed the status of the Main Hawaiian islands insular population in response to a petition to list the DPS as endangered under the Endangered Species Act (ESA). We published the final status review of the Main Hawaiian islands insular population in August 2010. And, in November 2010, we proposed to list the Main Hawaiian islands insular DPS as endangered under the ESA. In November 2012, we published a final rule to list the Main Hawaiian islands insular DPS as endangered under the ESA.
- NMFS published the False Killer Whale Take Reduction Plan in November 2012 to reduce bycatch in Hawaii’s longline fisheries.
- False killer whales were first known from fossils and were not discovered alive until 15 years after their fossils were found.
- Their species name, crassidens, means thick or dense tooth.
- Can be trained in captivity.