IUCN/SSC Otter Specialist Group Bulletin

©IUCN/SCC Otter Specialist Group

Volume 37 Issue 1 (January 2020)

Abstracts

Analysis of the Food-Web of a Population of Smooth-Coated Otters Lutrogale perspicillata (Mammalia: Mustelidae) in a Saline Littoral Mangrove Habitat
Pages 3 - 19 (Article)
Robyn, F. Wilson and Nityasa Namaskari
Aquaculture expansion, human-population pressure and retaliatory killing are threatening the smooth-coated otter (Lutrogale perspicillata) in mangrove habitats in Peninsular Malaysia. Our aim was to determine the diet of the smooth-coated otter (SCO) in a mangrove habitat, their feeding strategy and develop a food-web to inform the conservation of this species. We conducted spraint analysis and interviews with locals to identify the diet of SCO in the mangroves. We collected 91 spraints and identified 16 food items from six different taxa; fish, crab, shrimp, snake, barnacle and bivalve. Score bulk estimate and frequency of occurrence of prey were used to compare the importance of different taxa in the diet and this along with gut analysis of fish in the area were used to build a food-web. We found no dominate taxa but seasonal differences in their diet. SCO specialized on fish, crab and snake with fish comprising 44% and crab 43% of the diet. Fish occurred more frequently in the diet in the wet season and crab in the dry season. We conducted 25 interviews to determine tolerance of residents to SCO and to obtain feeding observations of them; no hunting was reported but SCO were disliked and harassed by fishermen and aquaculture farmers who saw them as competing for fish. The seasonal feeding strategy of SCO in mangrove habitat may have a greater effect on structuring the community than if their diet was dominated by fish. Conservation efforts need to focus on preventing future loss of mangroves; this may also reduce conflict between aquaculture farmers and otters.
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Holt-Based Activity Patterns of Smooth-Coated Otter (Lutrogale perspicillata) in the Lower Kinabatangan Wildlife Sanctuary, Sabah, Malaysia
Pages 20 - 28 (Article)
Leona Wei, Meaghan Evans, Henry Bernard and Benoit Goossens
Despite being one of the most biodiverse regions in the world, not much is known concerning the ecology of the otters on Borneo. We conducted a study to document the activity patterns of the smooth-coated otter, Lutrogale perspicillata, in increasingly disturbed and fragmented habitats in the Lower Kinabatangan Wildlife Sanctuary (LKWS), located in the Malaysian state of Sabah, northern Borneo. The aim was to gather ecological information for establishing baseline data and to understand better the otter behavior in this region of Sabah. We deployed camera traps at active otter holts, grooming and sprainting sites for 15 non-consecutive months and utilized the photographs to model the activity patterns of the otter using kernel’s density estimate modeling. Results showed that L. perspicillata in the LKWS was mainly crepuscular, with otter activity mainly occurring during early morning (0600 h) and late afternoon (1600 h - 1800 h). Grooming activity peaked at 0600 h while sprainting activity peaked at both 0800 h and 1700 h. We suggest that activity patterns of L. perspicillata may be influenced by prey availability, human disturbance and environmental temperature.
Contents | Full Text + Links | PDF (636 KB)

Eurasian Otter (Lutra lutra): Exploring Evidence in Nepal
Pages 29 - 37 (Report)
Aarati Basnet, Bhuwan Singh Bist, Prashant Ghimire and Paras Mani Acharya
The Eurasian otter (Lutra lutra) has been reported to be widely distributed in mountain wetlands of Nepal, though recent records have been scarce. The species is categorized as Near Threatened in the National Red List Assessment estimating its population as 1,000-4,000 individuals which is not based on a comprehensive status survey. Here, we review the past reports of the status and distribution of Eurasian otters in Nepal, and provide an update on the basis of literature review and a limited test surveys of some wetlands. We conclude that there has not been a single verifiable and conclusive record of the Eurasian otter in Nepal in recent years. Recent verifiable reports of otters have been entirely of smooth-coated otters. We suggest that there may have been a dramatic countrywide decline of Eurasian otter from their former ranges. Anthropogenic threats, illegal trade and habitat degradation threaten otter species throughout Asia, and reliable scientific and genetic studies are needed to get clear understanding of Eurasian otter status in Nepal
Contents | Full Text + Links | PDF (779 KB)

Fenced Fisheries, Eurasian Otters (Lutra lutra) and Licenced Trapping: an Impact Assessment
Pages 30 - 44 (Article)
Daniel Allen, Jake Devoile, Alex Nojebas, Simon Pemberton, Dave Webb and Lesley Wright
The endangered Eurasian Otter (Lutra lutra) became a protected species in England and Wales in 1978. The gradual recovery of the species coincides with the rise in specimen fishing on stillwater fisheries and increased concerns about predation. Although otter-proof fencing has been identified as the most effective medium-long term solution, the lack of a formalised legal mechanism to remove otters from fenced fisheries compromised livelihoods and otter welfare. Recognising this, the UK Wild Otter Trust (UKWOT) successfully lobbied for a licence to humanely trap and remove them. This paper examines the initial media and stakeholder responses to Natural England introducing the CL36 ‘Class Licence’ to live capture and transport Eurasian otters (Lutra lutra) that are trapped in fenced fisheries to prevent further damage. The paper analyses the UKWOT ‘Interventions Spreadsheet’ for the three years of the CL36 licence (November 2016 to June 2019) and the AT Fishery Management Advisors (FMA) ‘Otter Log’ (March 2017 to March 2019), to trace otter-related enquiries. Finally, the paper assesses the impact of the licence in practice, with reference to the successful live trapping and removal of otters from fenced fisheries.
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What is Lutra paranensis Rengger, 1830 ?
Pages 45 - 57 (Article)
Paul Smith
Described from Paraguay, Lutra paranensis Rengger, 1830 has long been associated by international authors with the Giant Otter Pteronura brasiliensis. However regional South American authors in the early 20th Century applied the name to the Neotropical River Otter Lontra longicaudis. The validity of each of these positions is evaluated by comparing the description with both species and the name is found to have been proposed for, and therefore correctly to apply to L. longicaudis.
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