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Shy, elusive and nocturnal otters important for ecosystem
They are shy, elusive and nocturnal. In a clear case of ‘mistaken identity’, the one and only species of their kind slinking around the wetlands of Sri Lanka are often thought to be mongooses and not taken much notice of.
Coincidentally though, as the world prepares to celebrate International Otter Awareness Day on Wednesday (May 27), the National Zoological
The otter pup at Pinnawela. Pic courtesy of the Zoo
It is Deputy Director Renuka Bandaranayake who on a recent visit to Giritale found that the Department of Wildlife Conservation had rescued two stranded otter-pups and brought back the “cuties”, cuddling them on her lap during the long journey back, to be cared for at the Pinnawela zoo.
“We have been looking after them like human babies, feeding them milk every three hours until they can grow to an age when fish would be their food,” said Ms. Bandaranayake, visibly upset that one pup had died in spite of all their efforts.
Pointing out that an otter-couple has been at the Dehiwela Zoo for a long time, she says that although they littered a few times, they were very protective parents and did not allow the keepers to get close to the nest. These pups too did not survive.
While many of us pay scant regard to otters though they are an important part of the ecosystem, Sri Lankans also seem to be unaware that there are two otter experts within our ranks.
Based on home-ground is Peradeniya University’s now retired Senior Zoology Professor Padma Kumari de Silva, who has been studying otters for a very long time. While she is Chair Emeritus of the Otter Specialist Group (OSG) of the International Union for Conservation of Nature (IUCN) from 2011 to date, she is also Asian Coordinator – IUCN/SSC-OSG from 1999 to date. The SSC is IUCN’s Species Survival Commission.
The other Sri Lankan on the IUCN/SSC-OSG is environmentalist Vasantha Nugegoda better known for his work with elephants on the international scene.
Prof. de Silva who is also the Asian Coordinator for the International Otter Survival Fund which holds the International Otter Awareness Day underscores the need to make people aware of the dangers faced by otters and redress the situation. The otters in Sri Lanka, assigned the sub-species Lutra lutra nair are the only mammalian residents of the rich variety of freshwater habitats.
“Otters are at the top of the aquatic food chain and are also sensitive to any disturbance, pollution and habitat destruction. As such they provide warning signals on the ‘health’ of the environment which is vital for the wellbeing of humans,” she says.
Lamenting that the focus is always on high-profile mammals such as elephants and leopards, she is of the view that in most Asian countries the otter is a neglected animal. “This is why it is necessary to turn the spotlight on otters, the top mammalian carnivores in most of the fast disappearing wetland habitats.”
She says that only a few realise that just as much as humans need clean water for their existence, otters do too. Otters cannot live in polluted waters. When they disappear from a particular aquatic habitat, it is most often because there is too much human interference or because the water is becoming polluted. In fact, otters are considered a useful ‘indicator species’ of aquatic pollution. However, their numbers are declining throughout Asia due the destruction of their habitats and pollution of waterways.
Deforestation in general and the destruction of riparian and marginal vegetation in particular are detrimental to the existence of these animals. This situation prevails in Sri Lanka as well. Development projects such as housing and road construction have brought about unbelievable disturbances to every corner of the island. This is bound to affect the quiet life and existence of this elusive animal, she adds.
Other threats, according to Senior Prof. de Silva, include otters being considered as enemies by humans because they compete with fisher-folk for fish in inland water bodies or invade fish and prawn culture ponds.
Although, they are killed for their fur in several Asian countries, fortunately this is not a problem in Sri Lanka, she says, adding that they are also sometimes hunted for their meat, but rarely in this country. “Organs of otters, such as their liver, kidneys and feet are used in traditional medicines in southeast Asian countries while their teeth are used in black magic! Fortunately, such activities are virtually unknown in Sri Lanka.”
While it is important to make people and governments aware of the importance of conservation of the otter, it is equally or more important to focus the attention of future generations on this important task, it is learnt. It is with this aim that a small project had been initiated to make Asian children aware of the importance of otters in the wetland habitat.
During the last two decades the IUCN/SSC-OSG had identified otter awareness programmes as a high priority in conservation in Asia, while in 2004, the Columbus Zoo Organisation, Ohio, USA, had funded a pilot project for the preparation of education material including story books, colouring books and jig-saw puzzles on otters, for children in Sri Lanka, it is understood.
Thereafter, in 2011, at the Otter Conservation Strategic Planning Meeting, attended by Senior Prof. de Silva, at the Columbus Zoo Organisation, the Otter Species Survival Plan Management Group had envisioned that an ex-situ and in-situ education plan would enable the achievement of conservation goals. The ex-situ educational pilot project initiated in Sri Lanka had then been supported and extended to other countries in the region.
Echoing Senior Prof. de Silva’s concerns, Mr. Nugegoda says that in his village in Kandy, he has not seen an otter in five years. This is probably due to the increase in the human population and the drainage of water and replacement of paddy fields with other crops. Pesticides also seem to have exterminated aquatic insects, crabs, frogs and fish which are the main prey of otters.
The once-forested edges of the streams, meanwhile, have been cleared, destroying their breeding areas and niche habitats, while the increasing stray dog population is hunting down the otters, are his views.
Mr. Nugegoda underscores that “drastic steps” are necessary to protect otters in Sri Lanka. These should include safeguarding streams and surrounding forests, not only by the Government but also by the people.
Those with large estates can create a safe habitat by making pools and introducing fish and amphibians for the otters. Abandoned paddy fields can be turned into protected zones by ensuring that the water is retained. Action also needs to be taken to contain the stray dog population, he adds.
For Mr. Nugegoda, the interest in otters was sparked when as a boy he saw lots of these “playful, boisterous and lovable” creatures in the streams in his village. He had also looked after several orphaned otter-pups, when he was working at the Dehiwela Zoo.
Recalling how he took three such otter pups to a friend’s home close to the zoo where he was staying he says they became part of the family. “They were extremely naughty and would sneak fish into the bedroom. They befriended the pet dog and when it barked would join it, squeaking loudly.”
Later during training at the London Zoo, he had the opportunity to study at the Otter Trust in Norfolk. “My mentor, Phillip Wayne was regarded as the person who saved the Eurasian otter in the United Kingdom. I learned a lot from him, in particular his experiences of hand-rearing otters with great care, while working towards sending them back to the natural environment,” he says.
Under Mr. Nugegoda’s next project, the creation of the world’s first night safari in Singapore, a successful exhibit was the otter habitat designed as a team. In the late 1990s, the Singapore Zoological Gardens and National Parks of Singapore undertook a project to re-introduce otters into the wild. “We created a sort of halfway house for these animals in Sungei Buloh National Park where they learned to feed on what was available in the environment. This was the first successful otter re-introduction in Asia and was widely praised,” he adds.