Marine otter | |
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In Huachipa Zoo, Peru | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Carnivora |
Family: | Mustelidae |
Genus: | Lontra |
Species: | L. felina |
Binomial name | |
Lontra felina (Molina, 1782) | |
Marine otter range |
The marine otter (Lontra felina) is a rare and relatively unknown South American mammal of the weasel family (Mustelidae). The scientific name means "feline otter", and in Spanish, the marine otter is also often referred to as gato 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 into fresh water or estuarine habitats. This saltwater exclusivity is unlike most other otter species, except for the almost fully aquatic sea 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, with guard hairs measuring up to 2 cm (0.79 in) in length covering dense, insulating underfur. The marine otter is dark brown above and on the sides, and fawn on the throat and underside. [5]
The marine otter has webbed paws and strong claws. The ventral side (underside) of the paws are partially covered in fur. It has 36 teeth and a dental formula of 3.1.3-4.13.1.3.2. The teeth are developed for slicing instead of crushing. The marine otter does not display sexual dimorphism. [5]
Marine otters are found in littoral areas of southwestern South America, close to shore and in the intertidal areas of northern Peru (from the port of Chimbote), along the entire coast of Chile, and the extreme southern reaches of Argentina. [1] Occasional vagrant sightings still occur as far afield as the Falkland Islands.
The marine otter mainly inhabits rocky shorelines with abundant seaweed and kelp, 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 a holt 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 a gestation 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 the sea 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 on fish, while those in northern Chile mostly feed on crustaceans and mollusks. [9] The otters on Isla La Vieja, Peru presumably prey on a colony of Peruvian diving petrels regularly. [10] In January 2009, one was seen preying on magellanic flightless steamer duck chick in Puñihuil. [10] The species shows opportunistic feeding behavior, sometimes eating small mammals and even fruit of plants like Greigia sphacelata and Fascicularia bicolor. [10]
The marine otter is of the Lutrinae, a subfamily of Mustelidae. Its exact taxonomy 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 on morphological data.
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Jong's proposed phenogram implied that the marine otter descended from the Asian small-clawed otter, and its closest relative being the North 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 on cytochrome b sequences. [12]
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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 and South 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 to Toxoplasma gondii infection along the northern and central coast of Chile, [14] though T. gondii seroprevalence in this otter species is lower than in other aquatic mustelids such as the southern river otter and American mink in southern Chile, [15] likely because of the general dryness of the former environment. [14] Nematodes and acantocephalans are also known endoparasites 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 of Argentina and the Falkland 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 under CITES Appendix I in 1976, and are listed as endangered by the U.S. Department of the Interior.
The Mustelidae are a diverse family of carnivoran mammals, including weasels, badgers, otters, polecats, martens, grisons, and wolverines. Otherwise known as mustelids, they form the largest family in the suborder Caniformia of the order Carnivora with about 66 to 70 species in nine subfamilies.
Otters are carnivorous mammals in the subfamily Lutrinae. The 13 extant otter species are all semiaquatic, aquatic, or marine. Lutrinae is a branch of the Mustelidae family, which includes weasels, badgers, mink, and wolverines, among other animals.
Toxoplasma gondii is a parasitic protozoan that causes toxoplasmosis. Found worldwide, T. gondii is capable of infecting virtually all warm-blooded animals, but felids are the only known definitive hosts in which the parasite may undergo sexual reproduction.
The sea otter is a marine mammal native to the coasts of the northern and eastern North Pacific Ocean. Adult sea otters typically weigh between 14 and 45 kg, making them the heaviest members of the weasel family, but among the smallest marine mammals. Unlike most marine mammals, the sea otter's primary form of insulation is an exceptionally thick coat of fur, the densest in the animal kingdom. Although it can walk on land, the sea otter is capable of living exclusively in the ocean.
Lontra is a genus of otters from the Americas.
The North American river otter, also known as the northern river otter and river otter, is a semiaquatic mammal that lives only on the North American continent throughout most of Canada, along the coasts of the United States and its inland waterways. An adult North American river otter can weigh between 5.0 and 14 kg. The river otter is protected and insulated by a thick, water-repellent coat of fur.
Lutra is a genus of otters, one of seven in the subfamily Lutrinae.
The giant otter or giant river otter is a South American carnivorous mammal. It is the longest member of the weasel family, Mustelidae, a globally successful group of predators, reaching up to 1.8 m. Atypical of mustelids, the giant otter is a social species, with family groups typically supporting three to eight members. The groups are centered on a dominant breeding pair and are extremely cohesive and cooperative. Although generally peaceful, the species is territorial, and aggression has been observed between groups. The giant otter is diurnal, being active exclusively during daylight hours. It is the noisiest otter species, and distinct vocalizations have been documented that indicate alarm, aggression, and reassurance.
The neotropical otter or neotropical river otter is a near-threatened otter species found in freshwater systems from Mexico and Central America through mainland South America, as well as the island of Trinidad. It is physically similar to the northern and southern river otter, which occur directly north and south of this species' range, respectively. Its head-to-body length can range from 36–66 centimetres (14–26 in), plus a tail of 37–84 centimetres (15–33 in). Body weight ranges from 5–15 kilograms (11–33 lb).
Aquatic mammals and semiaquatic mammals are a diverse group of mammals that dwell partly or entirely in bodies of water. They include the various marine mammals who dwell in oceans, as well as various freshwater species, such as the European otter. They are not a taxon and are not unified by any distinct biological grouping, but rather their dependence on and integral relation to aquatic ecosystems. The level of dependence on aquatic life varies greatly among species. Among freshwater taxa, the Amazonian manatee and river dolphins are completely aquatic and fully dependent on aquatic ecosystems. Semiaquatic freshwater taxa include the Baikal seal, which feeds underwater but rests, molts, and breeds on land; and the capybara and hippopotamus which are able to venture in and out of water in search of food.
The southern river otter, or South American river otter, is an otter species that lives in the southern regions of Argentina and Chile, including parts of Patagonia and Tierra del Fuego. It is listed by the International Union for Conservation of Nature as an endangered species.
The humpback smooth-hound is a species of houndshark and a part of the family Triakidae. The most noticeable difference between Mustelus whitneyi and its relatives, is the slight curvature, causing a "humpback" appearance located in front of its primary dorsal fin. It is found on the continental shelves of the tropical southeast Pacific, from Peru to southern Chile, between latitudes 3° S and 54° S. These sharks are demersal feeders but range from depths between 15 and 210 metres. Humpback smooth-hound sharks are small sharks, reaching a maximum size of 118 cm (46 in) in total length. Mustelus whitneyi typically feed on teleosts and invertebrates in the benthic and pelagic ecosystems, most important prey being the peruvian anchovy. These humpback smooth-hound sharks are placental viviparious sharks, meaning that the embryo forms inside the mother tethered by the placental cord. The threats currently causing population decline to humpback smooth-hound sharks surround issues with local fisheries and management.
The Congo clawless otter, also known as the Cameroon clawless otter, is a species in the family Mustelidae. It was formerly recognised as a subspecies of the African clawless otter.
Sea otter conservation began in the early 20th century, when the sea otter was nearly extinct due to large-scale commercial hunting. The sea otter was once abundant in a wide arc across the North Pacific ocean, from northern Japan to Alaska to Mexico. By 1911, hunting for the animal's luxurious fur had reduced the sea otter population to fewer than 2000 individuals in the most remote and inaccessible parts of its range. The IUCN lists the sea otter as an endangered species. Threats to sea otters include oil spills, and a major spill can rapidly kill thousands of the animals.
A mesocarnivore is an animal whose diet consists of 30–70% meat with the balance consisting of non-vertebrate foods which may include insects, fungi, fruits, other plant material and any food that is available to them. Mesocarnivores are from a large family group of mammalian carnivores and vary from small to medium sized, which are often less than fifteen kilograms, the human is a notable exception. Mesocarnivores are seen today among the Canidae, Viverridae (civets), Mustelidae, Procyonidae, Mephitidae (skunks), and Herpestidae. The red fox is also the most common of the mesocarnivores in Europe and has a high population density in the areas they reside.
The sea otter, Enhydra lutris, is a member of the Mustelidae that is fully aquatic. Sea otters are the smallest of the marine mammals, but they are also the most dexterous. Sea otters are known for their ability to use stones as anvils or hammers to facilitate access to hard-to-reach prey items. Furthermore, out of the thirteen currently known species of otters, at least 10 demonstrate stone handling behaviour, suggesting that otters may have a genetic predisposition to manipulate stones. Tool use behavior is more associated with geographic location than sub-species. Most behavioral research has been conducted on Enhydra lutris nereis, the Californian otter, and some has been conducted on Enhydra lutris kenyoni, the Alaska sea otter. Sea otters frequently use rocks as anvils to crack open prey, and they are also observed to rip open prey with their forepaws. While lying on their backs, otters will rip apart coral algae to find food among the debris. The frequency of tool use varies greatly between geographic regions and individual otters. Regardless of the frequency, the use of tools is present in the behavioral repertoire of sea otters and is performed when most appropriate to the situation.
Siamogale melilutra is an extinct species of giant otter from the late Miocene from Yunnan province, China.
Lontra weiri is a fossil species in the carnivoran family Mustelidae from the Hagerman Fossil Beds of Idaho. It shared its habitat with Satherium piscinarium, a probable ancestor of the giant otter of South America. It is named in honor of musician Bob Weir, and is the oldest known member of its genus. Prior to its discovery, Lontra was thought to have evolved from Lutra licenti, which dates from the Pleistocene of East Asia.
Neogale is a genus of carnivorous, highly active small mammals belonging to the Mustelidae family. Neogale contains four species: the Amazon weasel, the long and short-tailed weasels, and the American mink. Native to the Americas, members of the genus can be found as far north as Alaska and as far south as Argentina and Bolivia. Across this distribution, they thrive in a range of habitats, from the deep-freezes of the Alaskan and Canadian boreal forests to the arid desert southwest, and from the humid tropics of Central and South America to the windswept foothills of the Andes and northern Patagonia.