IUCN/SSC Otter Specialist Group Bulletin
© IUCN/SCC Otter Specialist Group
Volume 28 Issue 1 Pages 1- 60 (January 2011)
Abstracts
Predation by Neotropical Otters (Lontra longicaudis)
on Turtles in Belize
Pages 4 - 10 (Report)
Steven G. Platt and Thomas R. Rainwater
We report observations of turtle (Dermatemys mawii and Trachemys venusta) predation by Lontra longicaudis at Cox Lagoon, Belize. On 10 June 1994, we observed an otter swimming with a juvenile D. mawii in its jaws. During a subsequent search (25 June and 5 July 1994) we found 35 D. mawii shells or partially eaten carcasses, and a single, partially eaten adult T. venusta that had apparently been killed by otters. Based on the size of these turtles, juvenile and subadult D. mawii seem most vulnerable to otter predation. Because otter predation of D. mawii appears rare in Belize, and most reproductively mature D. mawii are probably too large to be caught and killed by foraging otters, we do not consider predation by L. longicaudis to be a serious threat to populations of this critically endangered turtle.
Contents | Full
Text + Links | PDF
(332 KB)
A Review of Violent or Fatal Otter Attacks
Pages 11 - 16 (Report)
Michael Belanger, Nicole Clough, Nesime Askin, Luke Tan and Carin Wittnich
In general, the public view of otters is often described as playful, curious and that they are not known for aggressive towards humans. As well, otter attacks seem to be under reported both in the anecdotal reports or scientific publications. In light of recent otter attacks in Florida, we reviewed all evidence of otter attacks on humans for any geographical and temporal relationships from the earliest (1875) to the most recent (Dec 2010). There was a total 39 anecdotal articles and 4 scientific publications found dealing with violent human-otter interaction (bites, attacks, deaths). The majority of attacks dealt with the North American otter (Lontra canadensis - 77%) and geographically occurred most often in Florida (38%). The greatest number of attacks occurred from 1990 to 2009 (51%). Within the 39 documented anecdotal reports of otter attacks, rabies was confirmed in 24 to 66% of the cases. Otters are known to be very territorial in nature and in North America, have had increases in population numbers. In certain areas where otters occur naturally (Florida), there has been a huge surge of human expansion, which has encroached upon the otter’s natural habitat. This encroachment into the otter’s habitat may be one reason for the recent increases of otter attacks upon humans.
Contents | Full
Text + Links | PDF
(123 KB)
The Use of Artificial Lakes on Golf Courses as Feeding Areas by the Otter (Lutra lutra) in Southern Spain
Pages 17 - 22 (Report)
Jesús Duarte, Miguel Ángel Farfán and J. Mario Vargas
During the spring and summer of 2010 evidence was found that otters were using artificial lakes on golf courses in southern Spain as feeding areas. The remains of carp and turtles eaten by the otters were found. The presence of these otters may be influences by distances to and connections with natural habitats of the species. The use of these lakes as a potential feeding area is occurring at a time when there is a great deal of environmental stress in the Mediterranean region.
Contents | Full
Text + Links | PDF
(557 KB)
Report of an Adaptive Reintroduction of a Juvenile Giant Otter (Pteronura brasiliensis)
Pages 23 - 33 (Report)
Diana Morales-Betancourt
Adaptive programs based on soft release and individual behavior changes may increase the survival rate of reintroduced giant otters (Pteronura brasiliensis). Key components of the program include the development of temporary enclosures and refuges, implementation of a responsive feeding program, an environmental adaptation program, as well as the use of a registered vocal repertoire and behavior information. This study was conducted by the Omacha Foundation, from March to June in 2008 in the Colombian Orinoco Ecorregion. The entire process occurred over 74 days, with 54 spent evaluating the animal, and the following 20 days spent implementing an intensive adaptive reintroduction program. The juvenile otter was successfully reintroduced, as evidenced by its repeated sighting after 17 months.
Contents | Full
Text + Links | PDF
(222 KB)
A Record of Small-Clawed Otters (Aonyx cinereus) foraging on an Invasive Pest Species, Golden Apple Snails (Pomacea canaliculata) in a West Sumatra Rice Field
Pages 34 - 38 (Report)
Aadrean, Wilson Novarino and Jabang
A small-clawed otter (Aonyx cinereus) survey in West Sumatran rice fields was conducted from April to September 2010. During this survey, golden apple snail (Pomacea canaliculata) shell remains were found on a rice field bank as suspected prey remains of small-clawed otters. This suspicion was later proved by the occurrence of snail material (pieces of operculum and shell) in otter spraints. This is the first evidence of small-clawed otters foraging on this invasive pest species. Characteristics of the shell remains and spraints are described.
Contents | Full
Text + Links | PDF
(191 KB)
An Evaluation of the Utility of Camera Traps in Monitoring Giant Otter Populations
Pages 39 - 45
Rob Pickles, Veronica Zambrana, Bill Jordan, Isla Hoffmann-Heap, Adriana Salinas, Jim Groombridge and Paul van Damme
Monitoring populations of giant otter, Pteronura brasiliensis, poses unique challenges. Important information such as sex, reproductive status, home range size and pack composition are often difficult to obtain during a short field season with limited observers. We conducted a pilot study on the use of camera traps to assist in monitoring a population of giant otters in the Bolivian Amazon. We found that while fewer individuals were resolved using camera traps than by direct observation, they were useful in complementing the observation approach to resolve pack membership and greatly facilitated the identification of the breeding pair. Camera traps were useful in resolving latrine activity patterns, the results of which are presented here.
Contents | Full
Text + Links | PDF
(202 KB)