Saturday, April 20

Guardians of our rivers and seashores


The Asian small-clawed otter is the smallest species of otter. – Photo by Sean Murray

THERE are many English villages with the prefix ‘Otter’.

In the north of England, I have visited two named Otterburn, one in Northumbria and the other in the Yorkshire Dales. From my home in Somerset I can see the Blackdown Hills, designated as an Area of Outstanding Natural Beauty.

The River Otter rises in these hills at Otterford before flowing southwest for 32km to the English Channel through the picturesque Devonshire villages of Upottery, Ottery St Mary, and Otterton. All the places mentioned were once the habitats of Eurasian otters, aquatic animals found in burns, becks, and rivers.

Peninsular Malaysia once hosted these otters but they were hunted to near extinction, much as in the UK (until the 1960s) for their furry pelts. Today the small-clawed otter maybe seen in Sabahan and Sarawakian streams and rivers.

The derivation of English and Malaysian words fascinates me, for the otter in Bahasa Malaysia is known as memerang. In folklore, if you obtained a kilir memerang or a stick found in an otter’s holt, you kept it as a charm against impotence.

In English, ‘otter’ was derived from the Old English word ‘otor’ stemming from a Proto-Indo-European language ‘wodr’ meaning water. Take your pick.


The smooth-coated otter is the largest of Malaysian otters. – Photo by Mike Prince


There are 13 species of otter so far identified, ranging from riverine and estuarine ones to those that are maritime, found in Eurasia, and in both North and South Americas, Japan, Southeast Asia, and in Africa.

Malaysia hosts four species of riverine, estuarine otters, and other species of sea otters. It is home for the smallest species, the Asian small-clawed otter (Aonyx cinerea) and the rarest otter in Asia – the hairy-nosed otter (Lutra sumatrana), both of which are found in Borneo.

Two other species, the larger smooth-coated otter (Lutrogale perspicillata) and a few of the Eurasian otter (Lutra lutra) may be found mostly in the peninsula. Lutra, by the way, is the Latin for otter.


Eurasian otter

This species is a large carnivore of the weasel family and whilst scarcely seen 50 years ago in the UK is making its comeback. Its scarcity is attributed to river pollution together with the activities of water-bailiffs’ hunts with otterhounds along stretches of a river where trout and salmon may be fished.

Growing up to a bodily length of 76cm with a 50cm long tail which is used as a rudder, its streamlined body and webbed feet can propel it at high speeds as it darts underwater.

With its waterproof chocolate-brown coat and small ears emerging from its dense fur, it has the inbuilt ability to close its nostrils and ears when diving almost seal-like when holding its breath. Preferring to hunt its prey by night over short stretches of a river, it is known to travel overland in search of fish in other rivers and lakes, and even cause chaos in fish hatcheries. Primarily feeding on eels, salmon, and trout, supplementary food is obtained from crayfish, ducks, crabs, and any fish in river estuaries.

To my very great surprise, just recently, I have seen otter footprints in riverside mud-banks near my house. These riverine mammals have five webbed-toes, which are often lopsided, hence four-toed tracks.

They breed at any time of the year with a gestation period of 60 to 90 days, producing a litter of two to four pups in a holt or nest, within a tunnel in the riverbank or under a riverside tree’s roots. The bitch and dog otters stay together to feed and romp with their young until the pups mature and can swim. The dog otter usually then takes off and the bitch is then ready for the next breeding season.

These otters, unlike sea otters, spend most of their lives on land, only entering rivers to feed. The presence of otters in rivers can be easily identified by their faeces or spraits, which stink of rotting fish and demarcate their territorial presence. Wild otters can live for up to 16 years and in captivity for even longer.

Fortunately, over the last 40 years, most British rivers have had a good clean-up through heavy penalties imposed on industrial and agricultural effluent sources. Otters have returned and on the River Otter they exist alongside an introduced, breeding European species of beaver. Beavers were last seen in England in 1550.


The hairy-nosed otter has a distinctive white upper lip ‘moustache’. – Photo by Rigeleus

Hairy-nosed otter

This species is not dissimilar to the Eurasian otter and may be found in Cambodia, Vietnam, southern Thailand, Indonesia, and Malaysia. It is the rarest of Asian otters, possibly verging on extinction, as it is in constant threat from the loss of lowland wet habitats, hunting for its pelt, and through accidental trapping in fishing nets.

Mainly found in larger inland rivers, it feeds on walking catfish, climbing perch, water snakes, crustaceans, and molluscs. Through the effect of climate change on the now unpredictable timings of monsoonal rain, these otters can be seen foraging in canals, drains, and even on prawn and fish farms.

With its distinctive, sun-bleached white upper lip ‘moustache’ and its long body, it is easily identified. I have spotted one of these clinging to a floating raft of aquatic plants in a Cambodian river. Sabahan records on the sightings of these otters date back to the 1890s, and whilst thought to extinct be there, they have again been recently spotted in the Tabin Wildlife Reserve.


Smooth-coated otter

The largest of all Southeast Asian otters, these are found in mangrove swamps, peat swamp forests, lakes, large ponds, and in paddy fields. Easily distinguished with their rounded heads, naked noses, and flatter tails, it is perhaps their short, smooth coat catching the sunlight that readily identifies them. Mating for life, unlike other otter species, the dog otter plays a very significant part in feeding the cubs and indeed rearing them.

In Bangladesh, tame and trained otters are used for driving fish shoals into nets. Besides mainly eating fish, the smooth-coated otter feeds on water rats, frogs, earthworms, and crustaceans or even the occasional bird.

Apart from man, alas, saltwater crocodiles are their main predators. As with most species of otter, their numbers are declining owing to losses in habitat through land reclamation and river and estuarine pollution, together with trapping for their pelts.


Asian small-clawed otter

This smallest of all the world’s species of otter, may, occasionally, be spotted along streams and rivers in search of fish, crabs and crustaceans. Undoubtedly, because of their small size, they are the most agile of the otter family.

If you are lucky, you may see these in lowland forest riverine environments in both Sabah and Sarawak and look out especially for their faeces composed of crab shells, fish bones, and fish scales. Like all otters they have a very soft under fur with a layer of protective hairs above. Between the two layers they trap an air layer, which insulates their body when diving deeper into rivers and estuaries.

In Malaysia it is illegal to own an otter but sadly social media has ignored buyers’ legal responsibilities, not only to themselves but, moreover, to these beautiful wild mammals that corrupt people seek to trap and sell as if they were domesticated pets.

Owners face criminal prosecution with heavy fines and prison sentences. Let otters remain in the wild, for where we can see an otter, then that river or estuary implies a healthy ecosystem free of pollutants from industrial discharges and agricultural pesticide runoff.