False Killer Whale (Pseudorca crassidens)

 

Class: Mammalia
Order: Cetacea
Family:    Delphinidae
Size:    Length: 14 to 19.9 feet (4.25 to 6 m)
Weight: 1.2 to 2.2 tons (1,219 to 2,235 kg)
Diet: Squid, octopus, cod, tuna, salmon, perch and even the occasional marine mammal
Distribution: Warm oceans and seas around the world
Young:  1 calf approximately every 7 years
Animal Predators:  Unknown
IUCN Status: No Special Status
Terms: Young: Calf  Group: School, Herd or Pod
Lifespan: Females: up to 62 years    Males: up to 58 years

 

Facts/Trivia:

·        False killer whales are often found in groups of hundreds of individuals.

·        The scientific name is Greek, meaning: pseudorca (false whale); crassidens (thick tooth).

·        False killer whales are also called “false pilot whales,” “blackfish” and “pseudorcas.”

·        They were unknown until the mid-1800s, when whalers discovered them in Kiel Bay.

·        The largest amount of false killer whales to be stranded on a beach at one time numbered over 150  individuals.

·        Like killer whales, false killer whales are members of the dolphin family. 

 

Description

Unlike orcas, false killer whales are completely black, although some may have gray markings on their undersides.  They have a long, slender body and a rounded beak, and up to 44 large, conspicuous teeth. Their flippers have a broad hump on the leading edge, which resembles a shoulder. They often emerge from the water with their mouth open.

 

Habitat

They range throughout tropical and warm temperate waters deep offshore, although they are not found in abundance in any location. Although they have sometimes been found as far north as Alaska and Norway, they usually prefer to remain in warm areas where the waters range from nine to 31 degrees C (48 to 88 F). It is believed that they may migrate seasonally. During hot summers, they venture as far north as British Columbia in the Pacific Ocean, and North Carolina in the Atlantic. 

 

Feeding Habits

False killer whales’ diet includes squid, octopus, cod, tuna, salmon, perch and even the occasional marine mammal. They have been observed sharing food with each other. 

 

Reproduction

Females begin to reproduce at age eight, with ovulation occurring only once per year. The female undergoes a 15-month pregnancy, after which a single calf, weighing 175 lbs (79 kg) and measuring five to six feet (1.5 to 1.8 m) is born. The calf nurses for two years, and offspring usually stay within the same herd as their parents for life.

 

Behaviour

They are called false killer whales because like orcas, they swim and hunt cooperatively in groups comprised of males, females and juveniles. They also may form mixed species herds with other cetaceans, most commonly bottlenose dolphins. False killer whales are fast, energetic swimmers and are able to leap completely out of the water. Their curious natures sometimes lead them to approach and even swim alongside boats. They make sounds similar to dolphins’ whistles and clicks to determine how far away objects are, based on the echo, and possibly to communicate amongst themselves. 

 

Conservation

False killer whales seem to be one of the most susceptible marine mammals when it comes to being stranded on beaches. There have been many reports of mass strandings of hundreds of beached false killer whales around the world, including Argentina, Australia, Europe, South Africa, Sri Lanka, New Zealand, Zanzibar, California and Florida. The reasons for these strandings remain a mystery. There is conservation concern for the false killer whale due to its low reproduction rate and small population. 

 

Sources

http://animaldiversity.ummz.umich.edu/accounts/pseudorca/p._crassidens$narrative.html

http://www.aquatic.uoguelph.ca/mammals/whales/accounts/false.htm

http://www.cetacea.org/fkiller.htm

http://www.nsrl.ttu.edu/tmot1/pseucras.htm

http://www.ifawct.org/whaledb/whale2.htm

http://library.thinkquest.org/C0124382/new_page_19.htm?tqskip1=1&tqtime=0302

http://rbcm1.rbcm.gov.bc.ca/programs/whales/s-falsekillerwhale.html

http://www.press.jhu.edu/books/walkers_mammals_of_the_world/cetacea/cetacea.delphinidae.pseudorca.html