Should you ever have an opportunity to see a live whale in the wild, consider it a breathless moment – a lapse in time that will forever be encapsulated in your mind
Based on the forthcoming book on whaling in Trincomalee by Chitral Jayatilake and Vimukthi Weeratunga
Whales belong to the cetacean family and bear the same characteristics as all other mammals although they’re especially adapted to living all or part of their life in the ocean. To stay warm in the ocean, most whales depend on a thick layer of fat known as blubber. And they can swim at speed because of their streamlined structure.
Many species can remain under water for long periods – and for this, they store extra oxygen in their muscles and blood. But they must surface to breathe.
Compared to land mammals, whales also have more blood in proportion to their body sizes. And interestingly, they can direct the blood flow only to vital organs such as the heart and lungs, and even slow their heartbeat to use less oxygen when diving!
Eons ago, whales were known to have been land creatures that resembled dogs and were more closely related to the hippo-potamus. Having evolved into ocean life about 60 million years ago however, these ancestors quietly adapted to survive solely in the water.
Their front legs evolved into paddle shaped flippers while they lost their back legs, and their tails grew larger and widened to form flukes. And of course, they developed the thick layer of blubber. Moreover, their skulls elongated and nostrils shifted to the top of their heads becoming blowholes to aid breathing at the ocean’s surface.
While these gentle giants spend all their life in the ocean, they’re warm-blooded, and give birth to the young and nurse them like humans do. In addition, they also have minute traces of fur. This is accentuated by a necessity to come to the surface to breathe through their lungs. With the passage of time, the anatomy of the whale evolved with specialised organs storing more oxygen in its blood as it became more adapted to diving.
There are two parvorders of whales: toothed and baleen whales. Separated around 34 million years ago, the aptly named toothed whale (odontocetes) has dental organs and one blowhole. There are over 73 species of toothed whales worldwide, and they include the sperm and beaked whales, belugas, narwhals, porpoises and dolphins, as well as fresh water dolphins that live in rivers.
Odontocetes range in size from the 60-foot (21.1 metres) sperm whale to the 5-foot (1.5 metres) vaquita. Treated as an intro-verted family member of the mostly eccentric tooth whale family, the beaked whales spend most of their time in deep waters and are rarely encountered by explorers. And excitingly, this is why new species are still being discovered!
True to their character, some beaked whales bear odd features with only the male population being blessed with teeth. And the strap toothed whales have only two teeth that wrap around the top of their jaws so they cannot fully open their mouths.
A somewhat lively pod, the toothed whale uses echolocation or sonar to detect objects in its environment much like bats do. It produces sounds in the air passages in its head, which are then projected out in front of it. These sounds bounce off solid objects and echo so that the animals can picture an ‘image’ of what is around them – a fascinating phenomenon that has attracted much attention and research.
Many species such as humpback and sperm whales appear to have individually identifiable calls. Orcas (also known as killer whales) live in groups or pods. And interestingly, each pod has a dialect or accent, in the same way that humans have accents depending on which part of the world they’re from!
Baleen whale parvorders (mysticetes) include 11 species that range in length from the pygmy right whale at 21 feet (6.4 metres) to the blue whale – the largest whale and the biggest animal on Earth at 100 feet (30.5 metres). Baleen whales have two blow-holes; and instead of teeth, they have hundreds of rows of baleen plates made of keratin.
Feeding by taking an enormous mouthful of food and water, and then pushing the water out through the gaps between their baleen plates, the baleen strains out small fish and plankton from the water for food.
Most baleen whales eat krill (shrimp-like animals) or small fish. Right and bowhead whales feed in a slightly different way – called skimming, water and food flow through a gap in the front of their mouth where the baleen is missing so as to trap food in the baleen fringe, while the water flows out between the baleen plates.
Even though baleen whales eat very small shrimps that are low on the food chain, they’re huge and consume great quantities in one go. Believe it or not, the blue whale that weighs up to 150 tons apparently eats four to eight metric tons of tiny shrimp every day!
Whales play an important role in stabilising the marine food chain and reproduction of other species through a benign form of geo engineering by participating in a trophic cascade, which means tumbling down from the top to the bottom of the food chain. Whales help regulate the flow of food by maintaining a stable food chain, controlling the population of certain animals by consumption in overpopulated areas.
Known to be blessed with a high level of intelligence, whales are also noted for their behaviour, echolocation, communication and environmental impact. This has led to many discoveries and advancements in sonar, aquatic environments, marine life and biology, and animal intelligence and behaviour, as well as other important oceanic fields.
Our growing understanding of whales is important to improve the measures we take to conserve all marine mammals as well as the oceans’ ecosystem.
Sri Lanka’s maritime zone is inhabited by 31 species of marine mammals that include the new sighting record of the Omura’s Whale. Though the existence of marine mammals in the waters surrounding the island has been known since the 14th century, thanks to the writings of historical travellers, official scientific explorations began only in the 1980s.
So what’s known about the diversity, ecology and conservation of marine mammals is based on the information that has been gathered by research conducted over the last three decades. The 31 species of marine mammals recorded in Sri Lankan waters are classified under the two groups of cetaceans and sirenians. Whales, dolphins and porpoises belong to the cetaceans, while manatees and dugongs are sirenians. Cetaceans in Sri Lankan waters include 29 species of whales, dolphins and porpoises while sirenians consist of only the dugong.
Sri Lanka’s location, and its marine topography with deep ocean canyons and weather systems, has created extremely hospi-table conditions in which marine mammals thrive. A narrow continental shelf of around 13.5 miles (22 kilometres) close to the shore ensures that the island’s plankton rich water attracts cetaceans. This makes the island one of the best places from which to observe the ocean’s giants in the shallows.
During the past decade, Sri Lanka has gained a reputation for being a treasure trove for whale and dolphin watching among both local and foreign tourists. This is mainly due to the spectacle created by the innumerable cetacean species. The most com-monly sighted cetacean around the island is the blue whale while the sperm whale (the largest toothed mammal in the world) is the next most commonly sighted.
Records of larger pods of sperm whales in Sri Lankan waters suggest that deep sea canyons are healthy enough to provide sufficient food sources to sustain large numbers of sperm whales.
Mirissa, Kalpitiya and Trincomalee are among the hotspots from which to watch whales and dolphins. But at present, there are no regulations to control or monitor whale watching. So the activity often poses a threat to marine mammals especially larger whales.
Lessons learned from other countries indicate that poorly regulated whale watching can damage and compromise marine mammal populations. As Sri Lanka plans to expand its tourism industry, marine mammals can prove to be an important economic resource as their sightings can be marketed as an enthralling travel experience. Indeed, this heightens the need for conservation.
With the fate of the whales lying in the hands of fishing nets and abandoned trash on the ocean floor, the elevated toxins in the waters only diminish the immunity and sustenance of these magnificent creatures.
Even activities such as whale watching can harass these mammals especially if the boats venture too close to them or separate mothers from their calves. Moreover, smaller whales are sometimes captured for display in hotels and aquariums to the detriment of their quality of life. And in some parts of the world, whales are hunted and served for consumption.
Many factors threaten the marine mammals that inhabit the ocean around Sri Lanka. Large numbers of dolphins and dugongs are killed annually both directly and indirectly (as by-catches) by fisher folk. Increased shipping traffic, marine pollution (by both land and marine based sources) and habitat destruction – especially shallow habitats like seagrass beds – are the other major threats faced by marine mammals.
Even though the island’s maritime zone is nearly eight times larger than its land area, there’s a substantial discrepancy in the allocation of areas for conservation.
This is evidenced by the fact that there are only four Marine Protected Areas in Sri Lanka compared to more than 100 protected areas declared on land. What’s more, these four protected areas are primarily aimed at conserving coral reefs rather than in consideration of protecting whales.
Popular movements around the globe have helped the salvation and regrowth of whales. Unfortunately, the multiple threats to whales have not been completely eliminated. We need to understand and resolve some of the problems that are currently threatening whales such as climate change, boat strikes, entanglement in nets and noise pollution.
It is by understanding the problem, spreading awareness and implementing solutions that long-term conservation can be as-sured.
WHALE WATCHING WITH NATURE TRAILS
Based in Mirissa off Galle, Nature Trails pioneered the launch of whale watching in Sri Lanka back in 2008. It continues to oper-ate as the leading operator off the east coast city of Trincomalee where the world’s third-deepest natural harbour sits in the beautiful aquamarine waters.
It offers marine mammal safaris by using small boats powered by 40 HP gasoline silent engines and expert seagoing naturalist guides – unforgettable moments with blue and sperm whales, as well as thousands of spinner and bottlenose dolphins, are on offer.
Nature Trails conducts private whale watching tours and clients from Europe, the US and Japan reserve informative guides each year to experience this amazing season, which peaks in March-April.
Based in Trincomalee at the 70-room resort Trinco Blu by Cinnamon, the seagoing team is headed by Sri Lanka’s most experi-enced whale watching guide Daya, so a whale of a time is assured!
Nature Trails also conducts professional underwater whale photographic and filming excursions under licence from the Department of Wildlife Conservation. Many celebrity underwater photographers have worked with Nature Trails in recent years in Trincomalee while special filming assignments at sea are arranged for networks and professionals with free expert divers.