| Marine otter | |
|---|---|
 | |
| In Huachipa Zoo,Peru | |
Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Carnivora |
| Suborder: | Caniformia |
| Family: | Mustelidae |
| Genus: | Lontra |
| Species: | L. felina |
| Binomial name | |
| Lontra felina (Molina, 1782) | |
 | |
| Marine otter range | |
Themarine otter (Lontra felina) is a rare and relatively unknownSouth Americanmammal of the weasel family (Mustelidae). Thescientific name means "feline otter", and inSpanish, the marine otter is also often referred to asgato marino: "marine cat". The marine otter (while spending much of its time out of the water) only lives in saltwater, coastal environments and rarely ventures intofresh water orestuarine habitats. This saltwater exclusivity is unlike most other otter species, except for the almost fullyaquaticsea otter (Enhydra lutris) of the North Pacific.
The marine otter is one of the smallest otters and the smallest marine mammal,[3][4] measuring 87 to 115 cm (34 to 45 in) from the nose to the tip of the tail and weighs 3 to 5 kg (6.6 to 11.0 lb). The tail measures 30 to 36 cm (12 to 14 in).[5][6] Its fur is coarse, withguard hairs measuring up to 2 cm (0.79 in) in length covering dense, insulatingunderfur. The marine otter is dark brown above and on the sides, and fawn on the throat and underside.[5]
The marine otter haswebbedpaws and strongclaws. The ventral side (underside) of the paws are partially covered in fur. It has 36teeth and adental formula of3.1.3-4.13.1.3.2.The teeth are developed for slicing instead of crushing. The marine otter does not displaysexual dimorphism.[5]
Marine otters are found inlittoral areas of southwestern South America, close to shore and in theintertidal areas of northernPeru (from the port ofChimbote), along the entire coast ofChile, and the extreme southern reaches ofArgentina.[1] Occasional vagrant sightings still occur as far afield as theFalkland Islands.[citation needed]
The marine otter mainly inhabits rocky shorelines with abundant seaweed andkelp, and infrequently visits estuaries and freshwater rivers. It appears to select habitats with surprisingly high exposure to strong swells and winds, unlike many other otters, which prefer calmer waters. Caves and crevices in the rocky shorelines may provide them with the cover they need, and often aholt will have no land access at high tide. Marine otters avoid sandy beaches.
Rocky intertidal zones with natural crevices are ideal for marine otter dens and feeding areas. Because most of their time is spent hidden in caves, their behavior is difficult to observe.
Marine otters actively avoid humans. In response to human activity, they will spend less time on coasts and stray from their dens during the day to fissures inaccessible to humans.[7] Though generally avoidant of humans, their inhabitance of fishing villages is an indicator of the marine otter's ability to adapt to urbanization.[8]
Marine otters may be monogamous or polygamous, and breeding occurs in December or January. Litters of two to five pups are born in January, February or March after agestation period of 60 to 70 days. The pups remain with their mother for about 10 months of parental care, and can sometimes be seen on the mother's belly as she swims on her back, a practice similar to that of thesea otter. Parents bring food to the pups and teach them to hunt.
Studies have shown latitudinal variations in diet, feeding periods, and dive time throughout the marine otter's distribution. Marine otters of southern Chile primarily feed onfish, while those in northern Chile mostly feed oncrustaceans andmollusks.[9] The otters onIsla La Vieja,Peru presumably prey on a colony ofPeruvian diving petrels regularly.[10] In January 2009, one was seen preying onmagellanic flightless steamer duck chick inPuñihuil.[10] The species showsopportunistic feeding behavior, sometimes eating smallmammals and even fruit of plants likeGreigia sphacelata andFascicularia bicolor.[10]
The marine otter is of theLutrinae, a subfamily of Mustelidae. Its exacttaxonomy has been debated due to lack of data. A phylogenetic study by C. G. Van Zyll De Jong in 1987 proposed the following phenogram of the lutrinae, based onmorphological data.
Jong's proposed phenogram implied that the marine otter descended from theAsian small-clawed otter, and its closest relative being theNorth American river otter.[11] A 2004 study contradicted Jong's research. The following was proposed as a part of the taxonomy of the Mustelidae, based oncytochromeb sequences.[12]
| |||||||
Human activity on coastlines poses disturbance to marine otters. Humans introduce domestic animals which may also disturb their dens.[7] Humans, as well as domesticated species, may expose a marine otter population to disease. Marine otters may be entangled in fishing nets and die.[10]
Microplastics have been found in the scat of marine otters.[13] The effects of microplastics in marine mammals are still unclear.
Gulls andSouth American sea lions may compete with marine otters for prey, the latter known to also attack the otters.[10]Orcas and sharks allegedly prey on the otters, though direct attacks have not been observed.[10]
Marine otters are known to be susceptible toToxoplasma gondii infection along the northern and central coast ofChile,[14] thoughT. gondiiseroprevalence in this otter species is lower than in other aquaticmustelids such as thesouthern river otter andAmerican mink in southern Chile,[15] likely because of the general dryness of the former environment.[14]Nematodes andacantocephalans are also knownendoparasites of this species.[10]
Marine otters are rare and are protected under Peruvian, Chilean, and Argentine law.[1] In the past, they were extensively hunted both for their fur and due to perceived competition with fisheries. Hunting extirpated them from most ofArgentina and theFalkland Islands. Poaching is still a problem, but one of unknown magnitude. It is unknown how many marine otters exist in the wild or what habitats should be preserved to encourage their recovery. Marine otters were listed underCITES Appendix I in 1976, and are listed as endangered by the U.S. Department of the Interior.
Media related toLontra felina at Wikimedia Commons
Data related toLontra felina at Wikispecies
