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Many of you know this animal as the killer
whale, however its scientic name is Ornicus Orca and is part of the family
delphinidae, which is a genera of marine dophins.
Killer Whales are easy to
spot because of their marks, a black back, white chest and sides, and a white
patch above and behind the eye. Males can be up 31 ft and weigh in excess of 6
tonnes but Females are smaller, reaching up to 28 ft and a weight of about 5 tonnes.
I’m sure many of you
recognize this animal or have heard about it through the movie Blackfish (Trailer
for blackfish: https://www.youtube.com/watch?v=G93beiYiE74)
and the scandle with SeaWorld, did you know the animal is also endangered?
It was listed as an endangered mammal on
February 16th, 2006. Southern Resident killer whales were designated
as a depleted stock under the MMPA in 2003. Killer Whales are primarily located
along the northeastern coast of Asia from eastern Russia to southern China. To
learn more about the extinction of the animal, check out this article on
national geographic.
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| The lighter coloration is where orcas live. National Geographic. |
Killer whales eat a large
variety of prey, including most marine mammal species. They have a diversity of foraging tactics, including
intentional beaching to gain access to seals onshore. They are known to use
cooperative techniques to herd fish and to attack large prey. Killer whales hunt in family pacts.
Studies have described
three distinct ecotypes of killer whales, called residents, transients, and
offshores. They are different because of ecological differences, differences in
coloration, external morphology, behavior and sound. The three different types
of killer whales maintain their distance.
The northeastern Pacific
residents love salmon and have a strong preference for one species, the chinook
salmon.
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| Google Images |
Transients in coastal
waters of the northeastern Pacific appear to eat small cetaceans and
occasionally take baleen whales.
Killer whales in coastal
Norway specialize on herring and on bluefin tuna. In the Antarctic, the killer
whales appear to specialize on minke whales, one smaller type eats mostly
seals, and yet another small form appears to be a fish-eater.
If you are
interested in orca culture, heres an article to feed your orca obsession!
But why has this wonderful animal been listed
as endangered?
Human impact has played a huge role in the
animal’s endangerment. Killer Whales have been exploited for many years in
several regions worldwide which is the main reason behind its endangerment.
Norwegian whalers in the
eastern North Atlantic took an average of 56 whales per year from 1938 to 1981.
The Japanese took an average of 43 whales per year along their coastal waters
from 1946 to 1981. The Soviets, whaling primarily in the Antarctic, took an
average of 26 animals annually from 1935 to 1979 and then took 916 animals in
the 1979/80 Antarctic season (Dahlheim and Heyning 1999; Reyes 1991). Killer
whales are still taken in small numbers in coastal fisheries in Japan,
Greenland, Indonesia, and the Caribbean islands (Reeves et al. 2003).
Other impacts have been oil spills, Moving boats can disrupt activities such as eating
and resting, and underwater boat noise could affect social and echolocation
signals of the whales. Lastly, the reduction of predation has played a huge
role.
However, there is hope! A
recovery plan has been devised.
There are five main concerns that need to be
addressed in order to save this species:
1. Protect
the Southern Resident killer whale population from factors that may be
contributing to its decline or reducing its ability to recover.
2. Protect
Southern Resident killer whales from additional threats that may cause
disturbance, injury, or mortality, or impact habitat.
3. Develop
public information and education programs.
4. Respond
to killer whales that are stranded, sick, injured, isolated, pose a threat to
the public, or exhibit nuisance behaviors.
5. Transboundary
and interagency coordination and cooperation.
Hopefully we can save this beautiful mammal
from extinction!
(By: Marie Leleu)
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