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The Blue Whale

Location: The Blue Whale exists in all the oceans of the world: the Arctic, Atlantic, Indian, and Pacific.

About

The Blue Whale (Balaenoptera musculus)

The Blue Whale (Balaenoptera musculus) is a marine mammal belonging to the suborder of Baleen Whales (called Mysticeti). At up to 37 metres (120 ft) in length and 181 metric tonnes (200 short tons) or more in weight, it is believed to be the largest animal ever to have existed.

There are three collections of the blue whale: those in the North Atlantic, the North Pacific and the Southern hemisphere.  They are concentrated in the Sea of Cortez, the Gulf of St. Lawrence, the Southern ocean, the Indian Ocean and near California.

The Californian coast has seen rising numbers.  A Blue Whale was spotted off the coast of Norway in 1998, which was the first sighting there in 30 years. None seem to be present near Japan, Alaska or the Bering Sea where they were/are most-hunted. 

The blue whale feeds in cold waters during the summer and migrates to temperate and tropical waters in the winter to breed. 

Balaenoptera Musculus means 'mouse-like finned whale' and is of the Cetacean order that is comprised of whales, dolphins and porpoises.  The name is thought to be a joke because of its great size.  It has a lifespan of 80 years. 

Appearance

The Blue Whale is generally parasite free, however, barnacles may grow on it.  It can pick up diatoms, microorganisms that live in the deep waters of the Antarctic, North Pacific and North Atlantic.  These give the underbelly a yellowish-green glow and are why early whalers called it “sulfur bottom.” It has the characteristic long grooves or pleats of the Rorqual whale.  These folds expand when the 'Baleen Whale' takes in large amounts of water while feeding. 

Dimensions

The largest animal on the planet, this tapered grayish-blue whale is as long as 3 school buses.  The longest ever recorded was captured in Antarctica and was 108 feet long.  Its heart is as big as car.  Males can weigh over 100 tons and the larger females 150. 

Social behavior

The blue whale generally lives alone or in pairs.  However, they can gather to form pods which contain up to 50-60 but a normal group is about a dozen.

Feeding

The Blue Whale feeds on krill, shrimp-like crustaceans called euphasids.  The blue whale ingests 4 tons of krill per day during its feeding season, about 40 million.  The blue whale’s feeding season is in the summer when it travels south to cold waters to find krill.  In the winter the blue whale fasts and lives off its blubber for 8 months.  In the Winter months, the Blue Whale migrates to warmer waters where it breeds.

The Blue Whale is a type of Baleen Whale. Baleen Whales are characterized by having baleen plates for filtering food from water, rather than having teeth. This distinguishes them from the other suborder of cetaceans, the toothed whales or Odontoceti. Baleen whales have 2 blowholes.

The song of the Blue Whale

The blue whale has the loudest and lowest-frequency sound of any animal.  At 180 decibels, its vocalizations travel thousands miles across oceans.  The male’s song is what wins him a mate.  To hear the blue whale go to Cornell University’s Bioacoustics Research Program at: http://www.birds.cornell.edu/brp/listen-to-project-sounds/blue-whale

Reproduction

It takes 6-10 years for the blue whale to reach sexual maturity.  A female reproduces every 1-2 years and the gestation period is over a year.  A newborn nurses for 7-8 months, drinking 100 gallons of milk a day and growing at the rate of 1-1 ½ inches a day.  It will weigh 23 tons when it is weaned. 

Speed 

  • The blue whale can reach speeds of 30 mph though it usually travels at about 12-14 mph.  
  • The size and speed of the blue whale kept them safe from early whalers.

Reason they are engangered

Hunting 

19th century 

The blue whale is endangered mostly due to the development of faster steam and diesel ships in the 1800’s. This advancement in shipping allowed hunters to catch and haul the Blue Whales.

Norwegian whaler, Sven Foyn, invented the exploding harpoon in 1868 and perfected the technique of inflating the speared whales so they wouldn’t sink.  

One blue whale produced 120 barrels of oil and so became a prized catch.  The peak of its slaughter was in 1931 when 29,000 blue whales were killed in one season.  It is estimated that about 350,000 blue whales were killed and 99% of the population wiped out.

20th century 

The International Whaling Commission (IWC) was created in 1946 and was made up of representatives from the whaling nations.  Its purpose was to preserve whale species in order to preserve the whaling practice.  Its first task was to establish the BWU, the Blue Whale Unit measurement of catch. A BWU (blue whale unit) = 2 Fin whales, 2.5 humpback whales or 6 Sei whales.

The IWC recognized the dwindling numbers of whales and created a moratorium to limit catch number.  The moratorium gave exceptions to Norway, Iceland, Japan and the aboriginal communities of Siberia, Alaska and northern Canada.

The limits set for the seasons whale catche was arbitrary.  Limits were raised after a year of high catch numbers on the assumption that high catches meant the populations were robust.  Limits were lowered after years of low yield due to the assumption that this outcome meant the whale population was low. 

The IWC banned the hunting of the blue whale in 1966 but left loopholes in the name of science.   The BWU was used until 1972. 

In 1967, 67,000 whales were killed, more than twice the number killed in 1933 when there were no restrictions. 

Throughout the 20th century, whaling nations ignored and cheated the ban, particularly Norway, Iceland, Japan, Russia and Korea. 

Quotas on catch for scientific research are established by IWC representatives of each country.  Japan and Norway consistently raise quotas, cheat quotas and add whale species to their research. 

In 1992 Iceland quit the IWC and Norway established its own commission to undermine the IWC’s authority. 

In 1994 Norway resumed the commercial hunt of whales.  In 1995 its computer program for determining the numbers of whale populations was found to be skewed.  In 1996 Norwegian traders were found with 6.1 tons of illegal whale meat. 

Japan spends much of its IWC years contributing large amounts of financial aid to developing Caribbean countries who switch from pro-conservation policies to pro-whaling. Japan lobbies for increased quotas and secret ballots at the IWC.  Illegal whale meat is found on Japanese fishing boats disguised as frozen prawns and DNA testing finds illegal whale meat in Japanese markets. 

In 1986 another moratorium is established by the IWC.  Korea stops whaling after a year.  Iceland continues until 1990.  Japan, Russia and Norway ignore the ban. 

The Marine Mammal Protection Act of 1946 prohibits the take of marine mammals in US waters and by US citizens.  It also prohibits the importation of marine mammals and their byproducts.  This may be why the largest concentration of blue whales (2000) can be seen along the west coast of the US. 

21st century 

The killing of the Blue Whale still goes on in the name of scientific research and illegal catches are found consistently. 

Numbers of whale catch and species increase in the name of scientific research for preservation. 

In 2000, Japan added 2 new species to its research quota and DNA tests found the meat of the West Pacific gray whale in a Japanese market, one of the most endangered species of animals in the world.   

Japan keeps its whale industry alive, in the hope of gaining enough votes to overturn whaling bans.  Interestingly enough, 2,700 tons of whale meat was processed into pet food in Japan because sales were so low.  The Japanese people associate whale meat with post-depression years and school lunches. 

Iceland rejoined the IWC in 2000 to enter objections and to begin scientific whaling.  Iceland makes $24 million yearly whaling with scientific loopholes.  

Whale watching contributes $1 Billion to the global economy a year. 

The IWF does not take advantage of genetic research methods.  DNA analysis using biopsy darts is non-lethal and yields greater amounts of data. 

Collision  

  • The biggest threat to the present-day blue whale is thought to be collisions with ships. 
  • Increased speed, volume and size of commercial boats along with smaller crews (due to advancing technology) contribute to ship-whale collisions. 
  • The US Navy has the highest rate of encounters with the blue whale. 
  • The National Oceanic and Atmospheric Association (NOAA) have proposed a “Ship Strike Reduction Strategy” that entails lowering speed limits and consolidating shipping routes in the North Atlantic to decrease blue whale deaths. 

Noise pollution 

Noise pollution is another reason whales are hit by ships and become beached.  Whales determine direction by echolocation and sea noise disturbs accurate sound wave readings. 

Noise pollution in the world oceans has increased due to:

  • Underwater testing by all the navies of the world  
  • Increased numbers of commercial vessels; sea traffic noise 
  • Increasing seismic events due to climate change, underwater earthquakes and eruptions 

Environmental pollution

A study of whales in the St Lawrence Seaway by Wheelock University looked at concentrations of pollutants in the blubber of the blue whale.  PCB’s and pesticides tend to associate with fat molecules.  The study found concentrated levels of PCB’s and pesticides in mother’s fat and milk.  A newborn blue whale ingests 100 gallons a day of its mother’s milk. Female blue whales were found to “unload” their toxic burden to their young each time they reproduced. 

Climate changes due to pollution greatly affect all marine life and the food supply of the blue whale.  

Warmer water temperatures have: 

  • Shown the increase in toxic algae blooms 
  • Increased the prevalence of parasites  
  • Sustained and introduced new viruses  
  • Reduced glacial ice that provides the phytoplankton food supply of krill 
  • Increased populations of organisms that compete with krill for the same food supply 

Reproduction 

The blue whale reproductive practices make for slow growth in its numbers. 

Blue whales exist in the northern and southern hemispheres.  Estimates of their numbers are 5-10,000 in the southern hemisphere and 3-4000 in the northern. 

These two populations never meet, mix and mate.  The two hemispheres have opposite winter (breeding) and summer (feeding) seasons.  When a northern hemispheric blue whale is in its breeding season, southern hemispheric blue whales are in their feeding season and at the regions farthest away from the northern blue whale. 

It takes 10-12 years for the blue whale to reach sexual maturity 

Its numbers have been so devastated that there is a small gene pool.  Less hardy specimens are bred and the low density means there is less chance of meeting a mate. 

The female’s 1-2 year reproducing intervals are one of the lowest reproductive rates.  A year-long gestation and 8 month nursing span contribute to this rate. 

Krill harvesting 

Krill are the anchor of the marine food chain.  They eat phytoplankton and algae and in turn are eaten by larger creatures that are in turn eaten by even larger predators.  Fish, whales, birds and seals depend upon steady supplies of krill. 

Krill have been harvested for thousands of years by many cultures.  Asian and Nordic countries still eat krill in different forms regularly.  Japan and Russia are among the biggest harvesters of krill. 

Recent health trends have touted concentrated krill in pill form as a far better anti-oxidant than fish oil and its high concentration of omega-3 fatty acids are thought to have anti-aging properties. 

An enzyme from processed krill is used to clean wounds and contact lenses. 

Fish meal is making up an increasingly larger part of krill harvesting and processing.  The rise in fish farms is contributing to this.  Krill is what gives salmon its pinkish hue.

Rising food costs and food shortages have already increased the commercial netting of krill.  In the past year catch yields rose from 109,000 to 684,000.  The search for sources of protein has contributed to Norway’s invention of a harvest and process procedure.  The ship is equipped to continuously and simultaneously catch and process batches of krill.

No one knows what the true numbers of krill are or what effects the increasing harvesting will engender.

Debris 

Enormous fishing nets that are set and left or lost kill many marine animals.  A 2003 study estimated that 308,000 marine animals are killed every year from entanglement in nets.  The number may be much higher as international statistics were not available.  Blue whales have been found in nets which get tangled around their flippers (as they spin to free themselves).

How you can help

Legal battles are the crux of the matter in the preservation of the blue whale.  Corrupt environmental practice and the lack of protection and law enforcement keep whale numbers at a low.

Besides pressuring your own politicians, many groups fighting for the preservation of the blue whale need funding and support.  These groups have a plethora of ways to join in the battle. Refer to the links below.

Coastal communities can keep their own whale watches and contribute to research.

References

  • http://www.marinemammalcenter.org/learning/education/whales/blue.asp
  • http://www.acsonline.org/factpack/bluewhl.htm
  • http://whale.wheelock.edu/bwcontaminants/welcome.html
  • http://archive.greenpeace.org/whales/whaling/IWC_timeline.html
Submitted by SFitz on Aug 31, 2008