The Blue Whale: Big in Size but not in Population

Ecology of the Blue Whale

 The blue whale, Balaenoptera muscukus, is a cosmopolitan species of baleen whale, which means blue whales are all over the earth in many different oceans. It is the biggest animal ever recorded on the surface of the earth, the females tend to be larger than the males and blue whales that are found in the Northern Hemisphere are generally larger than those found in the Southern Ocean. Blue whales can range up to 92 feet! When blue whales feed their throat and chest expand to allow space for all of the sea water and food that they intake simultaneously. Although they do not largely compete with humans for their food source of euphausiids, humans still pose a great threat to blue whales. They still get caught in fishing gear, are lethally struck by vessels, bothered by low-frequency noises, and are subject to habitat degradation.

Geographic and Population Changes


Blue whales are found in coastal waters, but often more offshore. Occasionally blue whales have been spotted off the coast of Cape Cod, Massachusetts in summer and in fall, also a bit further north in Canadian waters blue whales have been seen on the Scotian Shelf. Blue whales are very nomadic so they are seen almost everywhere around the world, not because of their population size but because of their habits of traveling from place to place. Humans have been the cause of the dramatic population changes of the blue whale, with vessel interactions, entrapment in fishing gear, habitat degradation, military, and hunting. Because of the large size of the blue whales they have been a major target of hunters, who believe that taking down an animal of the blue whales' stature is a big accomplishment. At least 11,000 blue whales have been killed by hunters during the late 19th century all the way to the middle of the 20th century.

Listing Date and Type of Listing

 Blue whales where listed as endangered on June 2, 1970, by the National Marine Fisheries Service. Although the recovery plan for blue whales was not enacted until July, 28, 1998, a whole 28 years later. The recovery plan has a list of seven objectives to address: "(1) determine population structure of blue whales, (2) estimate population size and monitor trends in abundance, (3) identify and protect essential habitats, (4) minimize or eliminate human-caused injury and mortality, (5) coordinate state, federal, and international actions to implement recovery efforts, (6) determine and minimize any detrimental effects of directed vessel1 and aircraft interactions, and (7) maximize efforts to acquire scientific information from dead, stranded, and entangled animals." (seven steps are attributed to the writers of the recovery plan, go to the link after this sentence to see, full recovery plan). http://ecos.fws.gov/docs/recovery_plan/whale_blue.pdf If these seven steps can be achieved the blue whales may someday be taken off the endangered species list.

Cause of Listing and Main Threats to its Continued Existence

The cause of the blue whale being listed is the enormous amount of hunting done by humans and the various interactions and pollution caused by humans. Their enormous size made them prize possessions of hunters and it makes them a target to a lot of incidental harm from various human activities. Humans are the main threat to the continued endangerment of the blue whales. Humans must be more careful around the habitats of blue whales to allow blue whale populations to reach the level that they once were at before hunting them left their whole population depleted. Blue whales are a very valuable component to the ecology of the sea and humans need to become more conscious in their efforts to help the blue whales return to prominence.

Description of the Recovery Plan


As mentioned above the seven step plan for recovery is centered around protection of the blue whales essential habitats because without them the blue whale could go from endangered to extinct. Humans play a major factor in the recovery plan of the blue whale, if the effects of humans can be largely lessoned or even completely eliminated blue whale populations would go up severely. Then last but certainly not least scientist continue to gather information from dead, stranded, and entangled blue whales in order to find out even more about what humans can do to help blue whales out instead of harm them.

Sources:

http://www.montereybayaquarium.org/animal-guide/marine-mammals/blue-whale

http://imgur.com/gallery/HyfVJIu

https://www.pinterest.com/infooffspring/blue-whales/

http://animalstime.com/blue-whale-facts-kids-blue-whale-habitat-diet/

http://ecos.fws.gov/docs/recovery_plan/whale_blue.pdf