Are you ready to protect blue whale in Sri Lanka?
Though human are the most intelligent and most powerful animal of the world, living on the
land, three quarters of the earth has covered by oceans with saline water exceeding the land
cover. The ocean is a wonderful creation of the earth that human never can finish its fully
exploration. The ocean science is extending by solving many mysterious & creating new
problems through chemically, physically, biologically, meteorologically, geologically,
lithologically and so on.
Ocean is the home of millions of ocean lives with great biodiversity. When the extinction of
different oceanic species is occurred, scientists have being finding new species day by day.
Among these millions of species, mammals are very important. Because of high amount of
foods and many other reasons some land mammals were totally adapted to marine
environment. Those are known as marine mammals belong to order cetacea.
Whales, the largest animals of the earth not only sea are also marine mammals belongs to the
order cetacea. They can be divided into two categories as toothed whales and baleen whales.
The suborder Odontoceti (toothed whale) includes the Sperm whale, Killer whale, Pilot
whale, Right whale, Narwhal whale and Beluga whale. Dolphins and Porpoises are also
included into this sub order.
The other suborder Mysticeti (baleen whales) is filter feeders. They feed on small organisms
(plankton & krill) by filtering seawater through a baleen build in lower jaw. This suborder
includes Blue whale, Fin whale, Humpback whale, Bowhead whale, Gray whale and the
Minke whale.
All Cetaceans bear forelimbs modified as fins, a tail with horizontal flukes, and nasal
openings (blowholes) on top of the head.
Blue whale is the largest animal that has ever lived on the earth at 30 m (98 ft) and 180 tones,
if in Jurassic era the world was handled by biggest reptiles of dinosaurs.They feed on 900-
4100 kg per day. The second largest animal is fin whale. Pygmy sperm whale is the smallest
whale at 3.5 m (11 ft).
Whales collectively inhabit all the world's oceans. For centuries, whales have been hunted for
meat, oil and as a source of raw materials. About 150,000 blue whales in 1930s in Antarctic
and 360,000 blue whales in 1900s in southern hemisphere were killed by humans for
different purposes. By the middle of the 20th century, however, industrial whaling had left
many species seriously endangered, leading to the end of whaling in all but a few countries.
Now there are only 10000-15000 blue whales on the earth.
The Sri Lankan sea is a best home for whales. Especially the southern coast of Sri Lanka is
good feeding ground for whales. There are many types of whales inhibiting southern part of
Sri Lankan sea such as blue whale, sperm whale, fin whale, sei whale, bryde’s whale, killer
whale, melon headed whale. Therefore whale watching industry has been developed mainly
in Mirissa (Sri Lanka) and few in galle (Sri Lanka).
All whales migrate long distance because of availability of pray, water temperature changes,
salinity changes, water depth, sea floor topography and some seasonal occurrences such as
formation of sea ice, wind driven currents and flooding of rivers. Sperm whale schools with
20 -40 individuals, Melon headed whales with 5 -15 individuals and one or few individuals
of other whales such as killer whale, fin whale, sei whale & bryde’s whale can be watched at
the southern coastal area of Sri Lanka. In addition to that mainly spinner dolphins and bottle
nose dolphin can be watched very commonly and easily at hundred meter channel.
Sperm whale Killer whale
But the most important and most interesting thing is watching the biggest animal that has
ever lived on the earth, blue whales. The wonderful thing is the blue whale population of the
southern coast of Sri Lanka doesn’t migrate. They stay same area every years inhabiting vast
area of southern coast. Blue whales feed on krill, plankton and small fish fries. That area is a
best feeding ground for blue whales with plenty of foods for them. The salinity, temperature,
pH of water is within the very suitable levels for their survival.
The seasonal occurrences are minimum and the sea topography also is in best condition. So
they don’t want to migrate another ocean they has become an isolated population. Actually
they are only a unique population of property of mother Sri Lanka. Therefore it is a very nice
bio resource of Sri Lanka. If you go every day to watch whales 99.9% sure you can see blue
whales every day easily without releasing huge efforts.
Blue whale (coming up) Blue whale (surfacing)
A blue whale is known as Balaenoptera musculus scientifically. It is a nice animal with eye
catching behavior patterns. Though it has mottled gray color surface a quite blue color can be
observed in underwater. The maximum length it can reach is about 33m (110 ft). Normally
females are 3m (10 ft) larger than males. They can grow up nearly 190 tons. The heart is
approximately the size of a small car. A blue whale’s arteries are so large that a baby can
swim. It contains 10 – 20 tons of blood. They have two blow holes like other baleen whales.
Blue whales like other baleen whales have a filtering system that is built in lower jaw. They
take plenty of water and food into the mouth and swallow the food after water is removing.
The big mouth consists with 500 – 900 plate of baleen. The tongue of mouth can be few tons
in weight. Each days during the feeding season they feed 3 -4% of their own body weight
(about 2 – 6 tons). The breeding season of blue whale like other baleen whales depend on the
season. A female blue whale gives birth to the biggest baby of the earth that is about 8m (26
ft) long and about 4 tons in weight. Like all mammals they look after their baby by giving
about 350 liters of fat - rich milk daily.
Blue whale (diving)
So there is a big trend to watch whale all over the world because of wonderful behavior
patterns of whales. When tourism is increasing rapidly after the war of Sri Lanka this
industry is also developing day by day. Because Sri Lanka is a best place of the world to
watch especially blue whales now Sri Lanka has become as the “land of the blue whales”
among foreigners.
Thus, increasing the participation of tourists, adding new organizers to the industry and
developing the competition among organizers can be seen. A world biggest shipping line is
running very closer to southern part of Sri Lanka crossing this blue whales living area.
The effect from ships The effect from boats
In this situation, it is highly affected very badly on these endangered blue whale population.
So we must take immediate actions to protect and conserve our blue whales.
E.P.D.N. Thilakarathne
Department of oceanography and marine geology
Faculty of Fisheries and Marine sciences & Technology
University of Ruhuna
