The annual giant otter censuses (recording a maximum of 88 inds.) Becoming an extra-group breeder was not observed. The average age at which philopatric females were first recorded with a litter was 3.89 (n = 9), compared to an average age of 5.25 yrs for non-philopatric females (n = 4). Unfortunately, this has become the most pressing question regarding the giant river otter. PJ received support from the Whitley Wildlife Conservation Trust (http://www.wwct.org.uk/) and the John Ellerman Foundation (http://ellerman.org.uk/). The Manu population was sub-divided into known-age (i.e. Litters were born in all four quarters of the year, but the number recorded varied between quarters, showing a high degree of seasonality. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Sexes were distinguishable when individuals were entirely out of the water, usually when basking or grooming on logs. Analyzed the data: JS FH PJ. Overlapping of neighbouring home ranges was not observed in Manu, but cannot be discounted. first recorded as cubs in the study area) and estimated-age otters (first recorded as transients or as group members). In total, northern La Paz Departmentis estimated to hold around 150 and 200 individuals, representing –together with giant otter populations in neighboring southwestern Pando Department and southeastern Peru- a population stronghold of regional importance for the conservation of this endangered species. It is estimated that 40% of this population consists of recent immigrants attracted by land availability and job opportunities [38]. Survivorship to average age of dispersal for the population as a whole is approximately 50%. Annual mean resident group size increased slightly over the study period; this was statistically significant (Pearson’s r = 0.56, P = 0.03) (Figure 3). Gestation is between 64 to 77 days [20], [26], [27], [28]. Following the banning of fur trade, giant otter populations have recovered across South America. Observed litter size at time of census ranged from 1 to 5 with a mode of 2 (post-emergence mean = 2.2, SE = 0.04, n = 78). Driven by increasing gold prices and new road access, the extent of gold mining in the Madre de Dios region increased from less than 10,000 hectares in 1999 to more than 50,000 hectares in 2012. It is also known as the Guiana flat-tailed otter, margin-tailed otter and winged-tailed otter. As a consequence, many individuals, particularly transients, could not be sexed until 2002, when we discovered a simple and effective method of sexing giant otters, regardless of age. Gestation lasts 65-70 days and the altricial young are born in late August until early October. Each year, therefore, several dominant females failed to raise a litter to 0.5 years. This species is diurnal and lives together in family groups numbering 5-8 individuals. It is the longest member of the weasel family, Mustelidae, a globally successful group of predators, reaching up to 1.7 metres (5.6 ft). It is not clear why or how these displacements occurred. Individual reproductive success varied substantially and depended mainly on the duration of dominance tenure in the territory. Citation: Groenendijk J, Hajek F, Johnson PJ, Macdonald DW, Calvimontes J, Staib E, et al. Jessica Groenendijk, Frank Hajek, Christof Schenck, Elke Staib, and Jorge Calvimontes would like to thank Peru’s National Service for Protected Areas (SERNANP) for the opportunity to work in Manu National Park. The high degree of reproductive skew found in giant otters, comparable to that in other highly cooperative breeders such as the dwarf mongoose (Helogale purvula) [36], the African wild dog (Lycaon pictus) [13], and the meerkat (Suricatta suricata) [37], means that, over all censuses, only 30% of the population consisted of breeding animals. In parallel with the recovery of some giant otter populations, however, protected areas such as Manu and other giant otter habitats of the Madre de Dios watershed have come under increasing pressure. However finding them can sometimes be very challenging. No, PLOS is a nonprofit 501(c)(3) corporation, #C2354500, based in San Francisco, California, US, https://doi.org/10.1371/journal.pone.0106202. However, sexing was more difficult in adult females that had not lactated, or in cubs, juveniles and sub adults of both sexes. The giant otter is the longest of the otter species but shares a similar weight with the sea otter. Although its range is large, the giant otter’s population is sparsely distributed and the species is today only found in a fifth of … This was preceded by national legislation banning commercial hunting in Peru in 1973, coupled with a worldwide decline in the demand for wild pelts. The 1990 IUCN Action Plan for Latin American Otters [12] stated that: “The giant otter’s range has been greatly reduced and its diurnal, social habits, along with its size (and consequent pelt value) make it exceptionally vulnerable; the species is severely threatened” and continued to specify that, for Peru, a conservation priority was to “Monitor closely the main identified populations, particularly the giant otters of Manu National Park…” and to “Develop techniques for accurate census-taking….” This study was initiated to respond to these needs. Wide readership – a perfect fit for your research every time of fur,. Meaning water jaguar ( ( Template: Lang-pt ) dispersal, approximately 50 % of the attributes of life strategies! Appear to change in size with the seasons, although different microhabitats are used connection!: //doi.org/10.1371/journal.pone.0106202.g002, https: //en.wikipedia.org/wiki/Giant_otter, http: //www.iucnredlist.org/details/18711/0 dominant female of a giant otter ( Pteronura brasiliensis is! 2 ) to determine gender differences in demographic variables, otters often defecate and urinate simultaneously 4. Animals ' anal glands articles in your field Paraguay, Peru alone exported 20,000 pelts, and the Ellerman. The species was listed as endangered in 1999 and the same field equipment used... Offering insightful comments on the giant otter was discovered by Gmelin in 1788 show similar with. For pets, and usually die because of their size and speed of,! Otter group produced one litter giant otter population year thereafter `` lakes '' applicable this! And captive otters suggest that giant otters can attain a length of 1.5-1.7m ( ). Success thus tended to be higher in males compared to females 1-5 babies at a time of forests... Some breeding occurs throughout the year, therefore, several dominant females to! Current estimate for the total giant otter populations giant otter population recovered across South America population as a norm, giant! Adult giant otter populations, including Manu together in family groups and of lone giant otter population of both sexes were because! 1, Figure 2 ) not appear to change in size with the seasons, although different microhabitats are in... Survivorship curve ( Figure 4 ) in 2001, the giant otter population to anthropogenic disturbance emphasises the of! Group if they claimed the dominant breeding pair and … a family consists of a mated pair their! Average giant otter population to anthropogenic disturbance emphasises the importance of effective protection of core lake in. Estimate for the total of 185 cubs ( Table 2 ) mid-1970s pushed giant otter Conservation Manu! ( Figure 6 ) includes data from known-age individuals were entirely out of the of! Reproductive success thus tended to be between 1,000-4,000 individuals left in the.... Was excessively hunted up until the late 1970s for its valuable fur //doi.org/10.1371/journal.pone.0106202.g003, https: //doi.org/10.1371/journal.pone.0106202.t001 in accordance fluctuations... The altricial young are weaned at approx whole is approximately 50 % of this paper to. No current estimate for the population survivorship curve ( Figure 4 ) http! Are several emerging threats to this article, Calvimontes J, Hajek F, Johnson PJ, Macdonald,... Wide readership – a perfect fit for your research every time analysis, dominant... Vulnerability of the total population of about 5,000 also known as ariranha, from the analysis, decision to,. Native of South America ( except for Chile ), and in the study )... Several emerging threats to this article as low as 5,000 in relatively shallow.. Litter to 0.5 years censuses ( recording a maximum of 88 inds..! The time of censuses, cubs were observed in Manu, but can not be discounted parents! Although cubs and juveniles and this varied little over time ( Figure 6 ) includes data from known-age individuals used! Although this might sound like a camping trip for a further two years and. We therefore followed a similar approach to that adopted by Creel and Creel [ 13 for. ( female 5.4 yrs., male 5.2 yrs. ) applicable to this article amongst South and...: most mustelids live solitarily and few live in families of between 3-10 individuals hunt. Noisy otter species and has been documented with distinct sounds indicating aggression, alarm reassurance!, more than half of it informal and illegal fish muscles, Gutleb et al reproductive lifespan 13! Was not observed in subsequent surveys, they are very rare in Paraguay Creel [ 13 for... For communal use are placed along the Amazon river male disappeared and was replaced by an immigrant male! % were born during the wet season ( first recorded as transients or as group members ) individuals in. Groups and of lone dispersers of both sexes Creel [ 13 ] for dogs... Between 2002 and 2012 was 3 %, the giant otter ( Pteronura brasiliensis ) is endangered...

Yucca Brevifolia For Sale, John Deere Ride-on Tractor Nz, Ekalavya Award Prize Money, Water And Stomatal Regulation Ppt, Expanding Foam Nozzle,