IUCN/SSC Otter Specialist Group Bulletin
©IUCN/SCC Otter Specialist Group
Volume 40 Issue 1 (January 2023)
Abstracts
Distribution, Habitat Selection and Diet of smooth-coated otters (Lutrogale perspicillata) in the Kollidam and Thenpennai Rivers in South India
Pages 3 - 15 (Article)
Ravikumar Jayasurya, Mahaly Moorthi, Selvarasu Sathishkumar, and Ravichandran Srimathi
We document the presence of the Smooth-coated otter (Lutrogale perspicillata) in the Kollidam River in Tamil Nadu and Thenpennai River in Puducherry, South India. Prior to this, there was no information about this animal in these Kollidam and Thenpennai Rivers, although the species is known to inhabit Tamil Nadu and Puducherry, where it is often found in mangrove ecosystems and estuaries. The Smooth-coated otter is currently listed as Vulnerable on the IUCN Red List. A total of 22 km of river bank were surveyed in 2019 and 2020, 15 km along Kollidam River and 7 km along the Thenpennai River. A total of twenty-seven individual otters were observed in the study areas, 15 along the Kollidam River and 12 along the Thenpennai River. Otter diet consisted of 53% and 46% fish, respectively, and included small percentages of insects, rodents, crabs, and prawns. Eight parameters, including leaf litter, loose soil and canopy cover were positively correlated with otter presence, while river width and depth and hard soil were negatively correlated. Smooth-coated otters appear to be threatened by poaching and habitat degradation in the area.
Contents | Full
Text + Links | PDF (1.2 MB)
Occurrence of Smooth-Coated Otters (Lutrogale perspicillata) in Mudasal Odai Coastal Backwaters, Tamil Nadu, India
Pages 16 - 25 (Report)
Udhayakumar Utthamapandian, Dipani Sutaria, Pichaiyan Francis, Rathinasami Arulmohan, Augustinraj Alex Kirubakaran, Davidkanagaraj Louwin Anand, and Ayyappan Saravanakumar
We document the presence of the Smooth-coated otter (Lutrogale perspicillata) in the Kollidam River in Tamil Nadu and Thenpennai River in Puducherry, South India. Prior to this, there was no information about this animal in these Kollidam and Thenpennai Rivers, although the species is known to inhabit Tamil Nadu and Puducherry, where it is often found in mangrove ecosystems and estuaries. The Smooth-coated otter is currently listed as Vulnerable on the IUCN Red List. A total of 22 km of river bank were surveyed in 2019 and 2020, 15 km along Kollidam River and 7 km along the Thenpennai River. A total of twenty-seven individual otters were observed in the study areas, 15 along the Kollidam River and 12 along the Thenpennai River. Otter diet consisted of 53% and 46% fish, respectively, and included small percentages of insects, rodents, crabs, and prawns. Eight parameters, including leaf litter, loose soil and canopy cover were positively correlated with otter presence, while river width and depth and hard soil were negatively correlated. Smooth-coated otters appear to be threatened by poaching and habitat degradation in the area.
Contents | Full
Text + Links | PDF (878 KB)
Distribution and Habitat Preference of Cape Clawless Otters (Aonyx capensis) and Water Mongooses (Atilax paludinosus) in the Soutpansberg, South Africa
Pages 26 - 38 (Article)
Céline Haring, Sina Weier, and Birthe Linden
Over 84% of the river ecosystems in South Africa are threatened and, accordingly freshwater dependent species such as the Cape clawless otter (Aonyx capensis) and the water mongoose (Atilax paludinosus) are also declining in numbers. These species share a similar diet and habitat preference and in certain places in South Africa it is known that they occur in sympatry. Our study focused on a pristine river system in the far western Soutpansberg where little is known about the local distribution and habitat preferences of these species. To determine the distribution and fine scale habitat preferences of otters and water mongooses, tracks and signs (TS) and camera traps were used, and spraint content analysed to establish differences in diet. Based on the TS that were found, the Cape clawless otter and water mongoose are both widely distributed along the river system and mostly occur separate from each other. The observed amount of TS of Cape clawless otters was higher in areas with pools, rocky riverbanks and areas with a stream width of 2 - >5 m in diameter. The number of water mongoose TS recorded was higher in wetland areas with leafy riverbanks and areas with a stream width of up to 2 m. We suggest that Cape clawless otters and water mongooses may avoid direct competition by habitat partitioning in the western Soutpansberg.
Contents | Full
Text + Links | PDF (1 MB)
Notes on Feeding Behaviour of Asian Small-Clawed Otters in Namdapha Tiger Reserve, Arunachal Pradesh, India
Pages 39 - 41 (Short Note)
Yumlam Benjamin Bida
Very little is known about the feeding habits and ecology of the Asian Small-clawed Otter (Aonyx cinereus) in their natural habitats, especially from the northeastern part of India, where intensive studies on Asian Small-clawed Otters, and otters as a group, are yet to be carried out. Herein we report two independent observations of Asian Small-clawed Otters preying on fishes in the rivers of Namdapha Tiger Reserve in Arunachal Pradesh, India.
Contents | Full
Text + Links | PDF (374 KB)
Results of the Fourth Eurasian Otter (Lutra lutra) Survey in Spain: 2014-2018
Pages 42 - 61 (Article)
Santiago Palazón Miñano
In the fourth national otter survey in Spain, 8,024 sampling points were carried out covering the entire Spanish mainland. Sampling unit used was the UTM grid (10x10 km). A total of 4,019 cells were prospected, representing 77.3% of the mainland Spain grids. Inside every grid, we made transects of 600 m distance (n=4,822; 60.1%) and spot-check (n=3,202; 39.9%). An overall value of 5,199 locations sampled with a positive presence of otter was obtained, representing 64.8%. Regarding UTM grids, 2,920 were otter positive, where at least one sampling point was found with valid otter traces or signals, representing 76.4% of the cells sampled. Percentage of the territory of mainland Spain with otter was 59.9%. Overall, the results were more positive in the Spain western half than in the eastern one, and more positive in the Spain northern half than in the southern one. By regions, the maximum percentage of positive sampling points and grids was reached in Galicia (north-western Spain), with 95.4% and 96.8% respectively. On the contrary, the minimum values of positive sampling points and grids were obtained in Valencia (eastern Spain), with 15.0% and 20.7% respectively. In relation to the third survey (2004-2006), otter has continued its spread, more slowly than a decade before, and mainly on Mediterranean basins. The numbers and percentages indicate a similar otter distribution in the 2000s and 2010s decades. In several territories, some cells with otter presence in the third survey were not sampled in the current survey; This fact has reduced the percentages obtained for the presence of otters in Spain.
Contents | Full
Text + Links | PDF (1.2 MB)