Articles on this page are available in 1 other language: Spanish (20) (learn more)

Overview

Distribution

Lontra longicaudis is present from Northwestern Mexico, south into South America; it is the most common otter in Mexico and has the widest distribution of the three S. American Lontra species.

The range extends into Uruguay, Paraguay, and across northern Argentina.

Biogeographic Regions: nearctic (Native ); neotropical (Native )

  • Lariviere, S. 1999. Lontra longicaudis. Mammalian Species, 609: 1-5.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© The Regents of the University of Michigan and its licensors

Source: Animal Diversity Web

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Range Description

Lontra longicaudis occurs from northwestern Mexico south to Uruguay (Gallo 1991), Paraguay, and across the northern part of Argentina to Buenos Aires province (Chehebar 1990; Cockrum 1964; Redford and Eisenberg 1992). It is widespread in the northern and central parts of Argentina (Bertonatti and Parera 1994).
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Historic Range:
South America

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Physical Description

Morphology

Lontra longicauda generally weighs less than 12 kilograms. Sexually dimorphic in size, the males average 20-25% larger than the females (Lariviere 1999).

L. longicauda is also known as the Neotropical otter. Head and body length can be 360-660 mm, length of the tail 370-840 mm, length of the hind foot 94-144 mm, and length of the ear ranges from 18-22 mm (Lariviere 1999).

Some average measurements of the long, flat skull include: basal length about 96.4 mm, zygomatic breadth 68.1mm, and postorbital breadth averaging 17.9 mm. The head is small and flat, bearing small eyes and short, round ears. The otter's neck is thicker than the head (Lariviere 1999).

The Neotropical otter has short, dense, sleek pelage, which is described as a lustrous grayish-brown. This otter is slightly paler ventrally, especially on the throat. On its face, the upper lip, mandible, and tip of the muzzle are silvery white to yellowish. The muzzle appears broad. The tail is long, wide, and quite thick at the base. It tapers to a point. The legs are short and stout, and the toes on all the otter's feet are webbed (Lariviere 1999).

Females have four nipples on the abdomen. The males have a well-developed baculum with a total length of around 72 mm. It has a small ventral groove, shallow at the proximal end and running deeper at the distal end (Lariviere 1999).

Range mass: 5 to 15 kg.

Range length: 360 to 660 mm.

Other Physical Features: endothermic ; homoiothermic; bilateral symmetry

Sexual Dimorphism: male larger

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© The Regents of the University of Michigan and its licensors

Source: Animal Diversity Web

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Ecology

Habitat

Lontra longicaudis generally shelters in a self-excavated burrow near permanent lakes or streams. They depend on a water environment with plenty of riparian vegetation (Nowak 1999).

One study looked at the use of shelters by the Neotropical river otter in Brazil, along the Betari River, between August 1993 and December 1994. There were several different types of shelters frequented by the otters. These shelter types include: a cavity among stones, cavity under tree roots, limestone dissolution cavity, cavity in a rocky wall, space among vegetation, and excavated burrows. The most common type of shelter used by the otters in this study was the cavities among stones (35.2%).This type of shelter is not deep and has a broad entrance. It is actually a space among pebbles and rock along the river bank (Pardini and Trajano 1999).

The Neotropical river otter is also known to use caves as shelters, which other otters tend not to do. A few of the caves were used to rear young. It was suggested the caves were generally far from the main river and were protected sites. These are features common to other otter rearing dens (Pardini and Trajano 1999).

It was also noted that otters' scent marking behavior is concentrated in those areas of the home ranges which they frequent more than others, in their activity centers. Along the Betari River, Lontra longicaudis did not concentrate its scent marks around shelters. Apparently, this means the shelters are not necessarily centers of activity for the otters in riverine habitats (Pardini and Trajano 1999).

Aquatic Biomes: lakes and ponds; rivers and streams

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© The Regents of the University of Michigan and its licensors

Source: Animal Diversity Web

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Habitat and Ecology

Habitat and Ecology
The Neotropical river otter lives in variety of habitats including natural systems such as deciduous and evergreen forests, warm and cool climate rainforests, and coastal savanna swamps (Emmons 1990). Habitat requirements include ample riparian vegetation (Bertonatti and Parera 1994; Redford and Eisenberg 1992), and abundant potential den sites (Soldateli and Blacher 1996). It favours clear, fast-flowing rivers and streams, and may be rare or absent from sluggish, silt-laden lowland rivers. It occurs mostly from 300 to 1,500 m of altitude, but has been found up to 3,000 m (Eisenberg 1989; Emmans 1990; Melendres 1978; Redford and Eisenberg 1992) and in Costa Rica and Uruguay it occurs below 300 m. The greatest abundances of Neotropical otters are in areas with extensive aquatic networks, low chemical and organic pollution, and low human density (Bardier 1992; Blacher 1987). However, this is a versatile species that tolerates environmental modifications well, and has been found occupying areas close to human activity such as irrigation ditches, rice fields and sugar cane plantations (Bertonatti and Parera 1994; Macdonald and Mason 1992).

It feeds mainly on fish, with crustaceans and mollusks contributing to large portions of diet in some areas (Bardier 1992; Bertonatti and Parera 1994; Gallo 1986; Helder-Jose and Ker De Andrade 1997; Passamani and Camargo 1995; Soldateli and Blacher 1996). Fish consumed are mostly from the families Cichlidae, Anostomidae, Characidae, and Pimelodidae (Passamani and Camargo 1995; Spinola and Vaughan 1995). Small mammals, birds, reptiles, and insects are consumed opportunistically (Bertonatti and Parera 1994; Parera 1993; Passamani and Camargo 1995).

It may compete with sympatric Pteronura brasiliensis, however, competition effects may be buffered by use of different habitat, denning sites, size of prey, and by the more crepuscular habits of L. longicaudis (Carter and Rosas 1997; Duplaix 1978). Known predators include anacondas (Eunectes) and jaguars (Panthera onca) (Duplaix 1978; Parera, 1996a), but caimans (Caiman), dogs, and birds of prey may also prey on neotropical otters (Dunstone and Strachan 1988; Parera 1996b).

Breeding occurs mostly in spring, but may occur throughout the year in certain localities (Parera 1996a). Gestation is 56 days (Bertonatti and Parera 1994), and litter size varies from one to five young ones (Bertonatti and Parera 1994), usually two or three (Parera 1996a).

Systems
  • Terrestrial
  • Freshwater
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Trophic Strategy

The neotropical otter feeds mainly on fish, crustaceans and molluscs. It is also an opportunistic feeder, eating insects, reptiles, birds, and small mammals. It has been suggested that foraging occurs all day, happening more commonly in the middle or late afternoon. Nocturnal activity is rare, but some neotropical otters have become completely nocturnal when their normal activities are disturbed by humans (Lariviere 1999).

L.longicaudis is a graceful swimmer and diver. They are always found in or near the water. Their foraging dives can last from 20-30 seconds. The otter consumes small prey while in the water but will take larger prey to the shore to eat it (Lariviere 1999).

Two separate studies were conduted regarding the feeding habits of the neotropical river otter and the results are described here. One study was conducted at a dam in the "Duas Bocas" Biological Reserve in Brazil, between July 1986 to July 1987. This reserve is covered mainly by the Atlantic Rain Forest. The study was based on otter fecal (spraints) analysis and compared with known species found in the dam. The material collected was resistant to gastric juice, including fish bones, rays, jaws, and teeth of a number of animals, plus crab and insect exoskeletons (Helder and DeAndrade 1997).

The most important food item was fish, which in this study was present in 97.2% of the samples. Also observed were crustaceans, amphibians, mammals, insects, and birds. Crustaceans were the second most commonly encountered food item. The authors indicated that greater abundance and easier capture of fish make them the main food item for the otters (Helder and DeAndrade 1997).

Between August 1993 and September 1994 another study was carried out in an Atlantic forest stream in south-eastern Brazil, the Betari River. Likewise, the author studied undigested remains in the otter's scat. In 93% of the samples fish was found. Aquatic insects and crustaceans were also found frequently (78.9%). The conclusion of this study was that otters are sometimes influenced in their selection of food items according to the availability of prey and its ability to escape (Pardini 1998).

These studies characterize L. longicaudis as a piscivorous mustelid that engages in opportunistic feeding.

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© The Regents of the University of Michigan and its licensors

Source: Animal Diversity Web

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Associations

There are a number of animals which prey on Neotropical river otters including anacondas, jaguars, caimans, dogs and birds of prey. Humans kill them for meat, fur, or incidentally in fishing operations, as these otters frequently get caught and drown in nets (Lariviere 1999).

Known Predators:

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© The Regents of the University of Michigan and its licensors

Source: Animal Diversity Web

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Life History and Behavior

Behavior

Perception Channels: tactile ; chemical

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© The Regents of the University of Michigan and its licensors

Source: Animal Diversity Web

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Life Expectancy

Lifespan, longevity, and ageing

Observations: Little is known about the longevity of these animals, but one specimen lived 14.9 years old in captivity (Richard Weigl 2005).
Creative Commons Attribution 3.0 (CC BY 3.0)

© Joao Pedro de Magalhaes

Source: AnAge

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Reproduction

Depending on the otters' locality, it breeds mostly in the spring, but may also breed throughout the year. Following a gestation period of 56 days, one to five young are born, but generally, there is only two or three in the litter. There is an indication of facultative delayed implantation, but it is not known how long the delay may be (Lariviere 1999).

Young are born blind, opening their eyes after 44 days. They are born fully furred. The young leave the den or nest when about 52 days old and spend most of the day playing near the natal den. At about 74 days post birth they start their aquatic activity with their mothers. Males do not provide any parental care.

Breeding interval: Neotropical otters breed once per year.

Breeding season: Some populations breed only in the spring, others throughout the year

Range number of offspring: 1 to 5.

Average number of offspring: 2-3.

Average gestation period: 56 days.

Key Reproductive Features: iteroparous ; seasonal breeding ; year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; viviparous ; delayed implantation

Average gestation period: 57 days.

Average number of offspring: 2.5.

  • Lariviere, S. 1999. Lontra longicaudis. Mammalian Species, 609: 1-5.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© The Regents of the University of Michigan and its licensors

Source: Animal Diversity Web

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Molecular Biology and Genetics

Molecular Biology

Statistics of barcoding coverage: Lontra longicaudis

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 0
Specimens with Barcodes: 2
Species With Barcodes: 1
Creative Commons Attribution 3.0 (CC BY 3.0)

© Barcode of Life Data Systems

Source: Barcode of Life Data Systems (BOLD)

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Conservation

Conservation Status

The Neotropical otter shows little fear of humans. All over its range the animal has been hunted for its valuable and beautiful pelt. The durable fur of river otters is used for coat collars and trimming. One estimate has about 30,000 otters being killed annually in Columbia and Peru alone during the 1970's (Nowak 1999).

During the period 1950-1970 L. longicaudis was heavily hunted and its numbers diminished greatly. From 1959-1972, at least 113,718 pelts were exported from the Peruvian Amazon. In Peru in 1970, over 14,000 pelts were exported and some believe this was only 50% of the animals killed (Lariviere 1999).

The Neotropical river otter is listed as endangered by the United States Department of the Interior, Appendix 1 of CITES, and also by the Mexican Ministry of Ecology. It is currently protected by many countries in its range including Argentina, Bolivia, Brazil, and many others (Lariviere 1999).

In Mexico, L. longicauda has disappeared from the highlands. Habitat destruction and fragmentation threatens the otter in the rest of the country (Nowak 1999).

In Argentina, due to excessive hunting in the 1970's, otter populations became very low. Once they received full protection in 1983, their populations recovered rapidly. Continued illegal hunting, water pollution and habitat destruction through ranching and mining are likely causes for the rareness of L. logicaudis (Lariviere 1999). A study of the wildlife in the lower delta of the Parana River in Argentina also shows that extraordinary floods in combination with human pressure has endangered the L. longicauda population there (Quintana et al 1992).

US Federal List: endangered

CITES: appendix i

IUCN Red List of Threatened Species: data deficient

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© The Regents of the University of Michigan and its licensors

Source: Animal Diversity Web

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

IUCN Red List Assessment


Red List Category
DD
Data Deficient

Red List Criteria

Version
3.1

Year Assessed
2008

Assessor/s
Waldemarin, H.F. & Alvarez, R.

Reviewer/s
Hussain, S.A. & Conroy, J. (Otter Red List Authority)

Contributor/s

Justification
This species is considered to be Data Deficient due to ongoing uncertainties about effects of numerous and diverse anthropogenic threats across its range on rates of population decline. The species has an apparent wide distribution along the original range, but there are no systematic studies to evaluate the size of populations and there is no standardized information about changes in the extent of occurrence or area of occupancy. Threats include deforestation, contamination and pollution of aquatic systems, hunting, agricultural activities, mining and damming. However there is no information about population size, number of mature animals or the cumulative effect of threats across the range of the species. This species is suspected to be threatened and further research is needed to inform rates of decline so that it can be assessed against the threatened categories.

History
  • 2004
    Data Deficient
  • 2000
    Data Deficient
  • 1994
    Vulnerable
    (Groombridge 1994)
  • 1990
    Vulnerable
    (IUCN 1990)
  • 1988
    Vulnerable
    (IUCN Conservation Monitoring Centre 1988)
  • 1986
    Vulnerable
    (IUCN Conservation Monitoring Centre 1986)
  • 1982
    Vulnerable
    (Thornback and Jenkins 1982)
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Current Listing Status Summary

Status: Endangered
Date Listed: 06/02/1970
Lead Region: Foreign (Region 10) 
Where Listed: South America


Population detail:

Population location: South America
Listing status: E

For most current information and documents related to the conservation status and management of Lontra longicaudis, see its USFWS Species Profile

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Population

Population
The species seems to be widespread, and its range does not seem to have changed, but there is no data available about population size, composition or distribution, so changes cannot be determined.

Population Trend
Decreasing
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Threats

Major Threats
Excessive hunting of L. longicaudis for its pelt in the period 1950-1970 resulted in local extinction over parts of its former range (Brack-Egg 1978; Donadio 1978). Although current hunting and population status are unknown (Emmons 1990), continued illegal hunting (Chehebar 1991), habitat destruction through mining and ranching, and water pollution are likely to be responsible for its rareness (Alho and Lacher 1991; Alho et al. 1998; Chehebar 1990; Gallo 1986; Melendres 1978). Neotropical otters show little fear of humans (Parera 1993), and are sometimes killed incidentally in fishing operations (Dunstone and Strachan 1988) or kept in captivity by fishermen who use trained otters to aid in fishing practices (Parera 1996a).
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Management

Conservation Actions

Conservation Actions
Lontra longicaudis is listed as endangered in the Appendix I of the Convention on the International Trade of Endangered Species of Wild Fauna and Flora (CITES; Emmons, 1990) and by the Mexican Ministry of Ecology (Ceballos and Navarro 1991). It is also listed as endangered by the United States Department of Interior. The neotropical otter is listed as a priority species by the Fundacion Vida Silvestre Argentina (Bertonetti and Parera 1994). This species is currently protected in Argentina, Bolivia, Brazil, Colombia, Costa Rica, Ecuador, Mexico, Nicaragua, Panama, Paraguay, Peru, Suriname, Trinidad, Tobago, Uruguay, and Venezuela (Aranda 1991; Brack-Egg 1978; Chehebar 1990; Mondolfi and Trebbau 1978). Neotropical otters are not legally protected in Guyana and Honduras, and no information is available on the distribution or legal status of neotropical otters in Belize, El Salvador, French Guiana, and Guatemala (Chehebar 1990).

Conservation priorities for the neotropical otter should focus on field surveys of current populations, identification of key habitats, protection of areas where high populations remain, and stricter regulations to prevent release of toxic waste in riverine systems (Mason and Macdonald 1990).
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Relevance to Humans and Ecosystems

Benefits

None known.

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© The Regents of the University of Michigan and its licensors

Source: Animal Diversity Web

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

In the past, the Neotropical otter was heavily hunted for its fur. During 1950-1970 this resulted in this otter becoming extinct over parts of its former range. The retail price of one L. longicaudis pelt around 1990, was U.S. $25-90 (Lariviere 1999).

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© The Regents of the University of Michigan and its licensors

Source: Animal Diversity Web

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Wikipedia

Neotropical otter

The neotropical otter or neotropical river otter (Lontra longicaudis) is an otter species found in Central America, South America and the island of Trinidad.[1]

They are physically similar to the northern and southern river otter, which occur directly north and south of this species' range. The length of the neotropical otter can range from 90–150 centimetres (35–59 in), of which the tail comprises about a third. Body weight ranges from 5–15 kilograms (11–33 lb).[2] Otters are members of the family Mustelidae, the most species-rich (and therefore diverse) family in the order Carnivora.

Since 2008, this otter has been classed as Data Deficient. This otter is found in many different riverine habitats; including deciduous and evergreen forests, savannas, llanos and pantanal. They prefer to live in clear fast-flowing rivers and streams. They are a relatively solitary animal and feed mostly on fish and crustaceans.

Characteristics[edit]

The neotropical otter is covered in a short, dark grayish-brown pelage. Fur color is lighter around the muzzle and throat.[3] They possess a long wide tail, with short stout legs and fully webbed toes.[4] Sexually dimorphic, the males are about 25% larger than the females. Body mass of the otter generally ranges from 5 to 15 kilograms. Neotropical otters will communicate with nearby otters via scent marking. Communication may also occur via whistles, hums, and screeches.[4]

The dental formula seldom varies from that of Eurasian otters, except in the few cases of otters that have dental anomalies.[5] Females and males have the same formula. The dental formula (for half the skull) is as follows:[6]

  • Upper: 3 incisors, 1 canine, 4 premolars, and 1 molar
  • Lower: 3 incisors, 1 canine, 3 premolars, and 2 molars

Diet[edit]

The neotropical otter's diet consists mostly of fish and crustaceans making up 67% and 28%,respectively, of its total diet. The otter will also occasionally feed on mollusks and small mammals. This otter is known to occasionally attack fishnets for a source of prey, hindering fishing productivity.[7] Otters living near marine habitats can have a much higher proportion of crustaceans in their diets.

Seasonality also greatly affect otters' food choice. During the dry season, when less fish and crustaceans are available, one study found a higher proportion of anurans in otters' diet. Though, during this time, anurans and reptiles still made up a very small percentage of the total diet. This might also be due to the fact that certain frogs mate during the dry season, so the frogs are easier prey. All in all, the distribution of available food species in a particular area roughly correlates to the percentage of each species found in otters' diet.[8]

Reproduction[edit]

Breeding occurs mostly in spring. Gestation will last 56 days and produce a litter of 1–5 pups.[3] The pups are born blind yet fully furred. They will emerge from their mother's nest when about 52 days and begin swimming at 74 days. They are raised completely by their mother, as males do not provide any parental care.[9] The male will only spend a single day with the female during breeding season. The female must keep her pups safe from predation by other neotropical otters. In one captive breeding situation, cannibalism by the mother may have occurred, though it was not confirmed.[10]

Communication[edit]

Like other otter species, neotropical otters will mark their territory with scratching or spraint (feces) in obvious places like rocks and under bridges.[11] Signs of marking may be most concentrated around their dens. They tend to only mark in certain areas of the den, separate from the activity center of the den. In caves, where a water sources may leak through the walls and wash away the scent, the resident may mark areas inside their den.[12]

Habitat and distribution[edit]

The neotropical otter has the widest distribution of all the lontra species. Their range can range from northwest Mexico to central Argentina. They prefer clear and fast-flowing rivers and are rarely known to settle in the sluggish, silt-laden lowland rivers. While mostly occurring at 300 to 1500 m above sea level they have been found settled at 3000 m.[13] They require abundant riparian vegetation and abundant den sites, but other than that the neotropical otter is very versatile and tolerant to environmental change. The otter will prefer sites that are solid, high, dry, and in proximity to deep water.[9] The Neotropical otter is the greatest generalist of all otter species. It can inhabit formidable habitats such as wastewater treatment plants, rice and sugar cane plantations, drainage ditches, and swamps. It can inhabit cold, glacial lakes in the Andes of Ecuador.[14] It can also live on the shorelines of marine environments hunting marine species and playing in the highly saline water.[15]

In an ecologically healthy area, there are many possible shelters so an individual can choose its preferred den. However, studies show that not all possible shelters are occupied and not all shelters are equally utilized by Neotropical otters. Otters visit different shelters with varying frequencies, from once or few times per up to many times per year. One factor that influences their preference for a den has to do with the water level, especially during flood season, when a den near water level can easily be washed away. A den may be at the water level, near the bank, or more than 1.5 meters about the water level.[12]

There are many other factors influencing otters' preferences for a shelter. Neotropical otters prefer dens near fresh water, high food availability, and relatively deep and wide water. During seasons with low water, individual otters may be more clumped because they will all move into areas of a river with deeper water, with more fish.[12] Deep, wide pools have been found to have a greater diversity of fish, preferential for otters. Some studies show that otters will forgo a less preferable, but more available den, like a muddy river bank, to spend more time in a preferential den, like a rocky shore.[16]

Neotropical otter females will rear pups in a den without a male. In some cases, a female may find a den that has space to keep her pups and a separate area for her own space. A study of a male otter's movement over 35 days showed he used three different dens without communication between them. Also, this individual moved between two islands separated by a one-kilometer wide estuary. He spent some time in a site with heavy mud, poor substrate for a den, so he may have been on the move to find food.[17]

Dens may have more than one opening, so the otter can easily exit to forage for food while staying safe from predators. There are many classifications of dens that Neotropical otters may use. A cavity among stones or under tree roots is preferred. In certain parts of South America, an otter may come across a limestone dissolution cavity or a cavity in a rocky wall. Though lacking a source of light, the Neotropical otter can make great use of this sturdy home. As a last resort, an otter expend energy to excavate a space among vegetation or a river bank, though those homes are less sturdy. Vegetative cover is also very important for the Neotropical otter. In comparison to other otter dens, the Neotropical otter dens do not have holes directly into the water, they do not use plant material as bedding, and will live in caves without light. They are elusive creatures and prefer undisturbed forests without signs of human activity. When humans clear forests for agricultural land, the number of available otter habitats plummets.[12]

Competition[edit]

The niches and ranges of the Giant river otter and the Neotropical otter overlap widely. Both species are diurnal and mainly piscivorous. The Giant otter is less of a generalist in habitat, preferring slow-moving water and overhanging vegetation, but where the Neotropical otter may also occur. The Giant otter is much larger and hunts in groups, so it can take larger prey. Some areas, like the Pantanal, have high enough productivity, so both otter species can exists with little or no competition. Additionally, Neotropical otters prefer deeper and wider streams than Giant otters.[14]

Conservation[edit]

The neotropical otter is listed as Data Deficient by the IUCN since 2008. The species is currently protected in Argentina and many other South American countries. Heavy hunting for its fur in the 1950s–1970s resulted in much local extinction over the otter's range. Illegal hunting, habitat destruction through mining and ranching, and water pollution still affect the population of the neotropical otter.[18] Although there have been attempts at captive breeding, they are largely unsuccessful.[3]

Most negative feelings about otters arise from fishermen who compete with the otter for fish. More data is needed to determine how much overlap exists between the fishermen's desired catch and the otter's diet. The highest competition between Neotropical otters and fishermen occurs during drought conditions. Fishermen may move out of their regular fishing areas, into deeper pools where the otter usually hunts in the absence of people. In a study on local fishermen's attitudes, the study revealed that fishermen's knowledge aligned with scientific data about the Neotropical otter's behavior, body description, and other data. Because the fishermen's facts aligned with scientific knowledge, scientists could then trust the fishermen's first-hand accounts about problems they experience with otters. Fishermen reported that otters will damage their fishing gear, but do not damage crab and shrimp nets. The locals have varying opinions about the otters' presence, from understanding they have to share space with the otters to wanting to kill the otters. Fishermen's knowledge and frequent contact with this elusive species might qualify them as the best managers of the species. There have been proposals to subsidize their fish profits lost to otters. However, it might be more beneficial to pay them to collect data on the species. This would benefit fishermen economically, improve fishermen's attitude toward the animal, and build on to currently insufficient data about this species. Fishermen usually have the greatest knowledge of the resource. Otters are rarely victims of being caught in gillnets, themselves, and very rarely die from the same cause.[19]

Neotropical otters are threatened by habitat degradation associated with: agriculture, soil compaction, pollution, roadways, and runoff. Also, when forests are cleared for cattle grazing, heavy vegetation (which is the otter's preferred habitat) near streams is also cleared or trampled by cattle. This species is a very important ecological indicator because they prefer ecologically rich, aquatic habitats and have a low reproductive potential.[16]

Captivity[edit]

One male and one female Neotropical otter were captured near Caucasia, Columbia and taken to Santa Fe Zoological Park in 1994 and 1996, respectively. Zoo staff observed the pair mating in the water, then separated the animals. The female had three births; one was successful. The infant deaths may have been unintentionally caused by the mother. One idea suggested the mother's enclosure was too small and she had no access to water, as she would have had in the wild. The mother's gestation period was 86 days for two separate breeding events recorded at this zoo. An 86-day gestation period is much longer than the previously accepted belief that gestation lasts around 60 days. Two possible explanations are: differences might exist between different subspecies or a later copulation may have occurred and not been observed. Also, this otter species might display short-term variation in gestation periods.[10]

Subspecies and taxonomy[edit]

The taxonomy of the genus has been debated but the use of the name Lontra rather than Lutra for New World otters is supported. The neotropical otter has a very wide range, covering a large portion of South America, so it is not surprising there are geographical structures separating some populations. One such geographical isolation is are the Cordillera Mountains. Additionally, the river in the Magdellena river valley flows north, away from the mountains, decreasing the likelihood that otters in the northern tip of South America will mix with otters elsewhere in the continent.

Neotropical otters have an interesting phylogenic relationship to other otter species. They are most similar to Lontra feline and Lontra provocax, which is not surprising considering these two species are found in South America. However, neotropical otters are relatively distantly related to Pteronura brasiliensis, which is surprising considering they have nearly identical ecological niches and home ranges.[20]

In one study, otters within a 1600 square mile area in southern Brazil showed low nucleotide variation, but high haplotype diversity compared to other otter species and other carnivores. The study made the conclusion that otters may be undergoing a recent increase in diversity. The results also show interrelatedness of otters nearby and give reason to separate the species into subspecies. More standardized DNA segments, better analytical methods, and more samples from other areas are needed for further knowledge.[21]

References[edit]

  1. ^ a b Waldemarin, H.F. & Alvares, R. (2008). Lontra longicaudis. In: IUCN 2008. IUCN Red List of Threatened Species. Retrieved 21 March 2009. Database entry includes a brief justification of why this species is of data deficient
  2. ^ Berry, K. (2000). Lontra longicaudis. Animal Diversity Web
  3. ^ a b c Bertonatti,C., and A. Parera. (1994). Lobito de rio. Revista Vida Silvestre. Nuestro libro rojo, fundacion vida silvrestre Argentina, Ficha No. 34
  4. ^ a b Emmons. L. H. (1990). Neotropical Rainforest Mammals, a field guide. The University of Chicago Press, Chicago.
  5. ^ Peters, F. B., Coelho, E. L., Vasconcelos, B. C. E., Roth, P. R. O., & Christoff, A. U. (2013). Dental anomalies in Lontra longicaudis (carnivora: mustelidae) collected in southern Brazil. IUCN Otter Specialist Group Bulletin, 30(1), 31–36.
  6. ^ Melissen, A. (2000). Husbandry guidelines for Lutra lutra. otterspecialistgroup.org
  7. ^ Alarcon, G.G. and Simões-Lopes, P.C. (2004) The Neotropical Otter Lontra Longicaudis Feeding Habits In A Marine Coastal Area, Southern Brazil. IUCN Otter Spec. Group Bull. 21(1): 24–30
  8. ^ Rheingantz, M. L.; Waldemarin, H. F.; Rodrigues, L. V.; Moulton, T. P. (2011). "Seasonal and spatial differences in feeding habits of the Neotropical otter Lontra longicaudis (Carnivora: Mustelidae) in a coastal catchment of southeastern Brazil". Zoologia (Curitiba, Impresso) 28: 37. doi:10.1590/S1984-46702011000100006.  edit
  9. ^ a b Parera, A. (1993) The Neotropical river otter Lutra longicaudis in Ibera Lagoon, Argentina. International Union for the Conservation of Nature, Otter Specialist Group Bulletin. 8:13–16.
  10. ^ a b Arcila, D. A., & Ramirez, M. (2004). Captive reproduction of the Neotropical otter in the Santa Fe Zoological Park in Medellin, Colombia. The IUCN/SSC Otter Specialist Group Bulletin, 2(1), 16–18.
  11. ^ Rheingantz, M. L., Waldemarin, H. F., & Kasper, C. B. (2004). Survey of Neotropical otters: testing methods to access distribution. The IUCN/SSC Otter Specialist Group Bulletin, 21A, 1
  12. ^ a b c d Pardini, R. (1999). "Use of shelters by the neotropical river otter (Lontra longicaudis) in an Atlantic forest stream, southeastern Brazil". Journal of Mammalogy 80 (2): 600–610. JSTOR 1383304. 
  13. ^ Eisenberg, J.F. Mammals of the neotropics. The University of Chicago Press, Chicago.
  14. ^ a b Munis, M. C., & Oliveira, L. F. B. (2011). Habitat use and food niche overlap by neotropical otter, Lontra longicaudis, and giant otter, Pteronura brasiliensis, in the Pantanal wetland, Brazil. The IUCN/SSC Otter Specialist Group Bulletin, 28(A), 76–85.
  15. ^ Alarcon, G. G., & Simones-Lopes, P. C. (2004). The Neotropical otter Lontra longicaudis feeding habits in a marine coastal area, southern Brazil. The IUCN/SSC Otter Specialist Group Bulletin, 21(1), 24–30.
  16. ^ a b Carrillo-Rubio, E., & Lafon, A. (2004). Neotropical river otter mico-habitat preference in west-central Chihuahua, Mexico. The IUCN/SSC Otter Specialist Group Bulletin, 21(1), 10–15.
  17. ^ Nakano-Oliveira, E., Fusco, R., Dos Santos, E. A. V., & Monteiro-Filho, E. L. A. (2004). New information about the behavior of Lontra longicaudis (carnivora: Mustelidae) by radio-telemetry. The IUCN/SSC Otter Specialist Group Bulletin, 21(1), 31–35.
  18. ^ Chehebar, C. (1990). Action plan for Latin American Otters. pp. 63–74 in Otters: an action plan for their conservation Pat Foster-Turley, S. M. Macdonald, Chris Mason (eds.), IUCN/SSC Otter Specialist Group.
  19. ^ Barbieri, F.; Machado, R.; Zappes, C. A.; Oliveira, L. R. D. (2012). "Interactions between the Neotropical otter (Lontra longicaudis) and gillnet fishery in the southern Brazilian coast". Ocean & Coastal Management 63: 16. doi:10.1016/j.ocecoaman.2012.03.007.  edit
  20. ^ Trinca, C. S.; De Thoisy, B.; Rosas, F. C. W.; Waldemarin, H. F.; Koepfli, K. -P.; Vianna, J. A.; Eizirik, E. (2012). "Phylogeography and Demographic History of the Neotropical Otter (Lontra longicaudis)". Journal of Heredity 103 (4): 479. doi:10.1093/jhered/ess001. PMID 22589556.  edit
  21. ^ Trinca, C. S.; Waldemarin, H. F.; Eizirik, E. (2007). "Genetic diversity of the Neotropical otter (Lontra longicaudis Olfers, 1818) in Southern and Southeastern Brazil". Brazilian Journal of Biology 67 (4): 813. doi:10.1590/S1519-69842007000500003. PMID 18278347.  edit

Further reading[edit]

  • Neotropical Rain forest Mammals, A Field Guide – Louise H. Emmons and Francois Feer, 1997
  • Mammalian Species- No609, 1–5. Lontra longicaudis. Serge Lariviere, 5 May 1999 by the American Society of Mammalogists.
Creative Commons Attribution Share Alike 3.0 (CC BY-SA 3.0)

Source: Wikipedia

Unreviewed

Article rating from 0 people

Default rating: 2.5 of 5

Disclaimer

EOL content is automatically assembled from many different content providers. As a result, from time to time you may find pages on EOL that are confusing.

To request an improvement, please leave a comment on the page. Thank you!