Giant Otter

• Description

  • Physical description of the animal (with at least 3 pictures)

Their coats are dark brown with several white or yellow patches on the throat and chin. The patterns of these patches are unique to each otter. They also have webbed feet, water-repellent fur to keep them dry and warm, and nostrils and ears that close in the water.

• Point key characteristics of species

The skull of the giant otter is long and flattened and can contain 34-36 teeth. The coat is mainly brown or gray and is usually darker on the back and lighter on the chest, throat, and underside.

• Size

Length from head-to-tail is approx. 6 ft.

• Weight

They weigh between 40 and 70 pounds

• Life Span

It is estimated the life expectancy is between 10 and 13 years in the wild.

• Differences between Males and Females

Females are smaller and lighter than males.

• Description of the Habitat

  • How much rainfall

Over a year the Amazon basin get 6 to 10 feet of rainfall

• Plants

Water lilies, grasses, shrubs and short trees

• Animals

catfish, perch and characins but also eat small snakes, caimans and crustaceans.

• Temperature

10‒42 ℃

• Terrain

the giant otter is always associated with some form of freshwater river, stream, or wetland.

• Distribution

  • Continents found: South America

  • Invasive at all: They are not an invasive species.

• Diet

  • What exactly does it eat: mostly catfish, perch and characins but also eat small snakes, caimans and crustaceans.

  • How often does it eat: between 6 and 10 pounds of fish a day.

  • How does it get it’s food: with their teeth

  • Any special foods: none

• Social Structure

  • Live in packs or solo: A giant otter social group consists of an adult pair, one or more subadults, and one or more juveniles

  • Roles within community: Group members will share roles. Males actively participate in rearing cubs and family cohesion is strong;older, juvenile siblings also participate in rearing, although in the weeks immediately after birth, they may temporarily leave the group. They are very territorial.

  • Male or Female led groups: both :led by a dominant breeding pair

  • Individuals that make up the group: Giant otters live in groups up to 10 individuals, with groups comprising a monogamous pair and their offspring from several generations.

  • How do they interact with each other: Adults communicate using 22 distinct vocalizations, while pups use a different set of 11 sounds to call to each other.

• Reproduction

  • How often do they mate: Females are receptive for 3-10 days of the 21 day estrous cycle. Swelling of the nipples and vulva signal receptivity.r

  • How many mates do they have: one

  • Time of year for mating: Peak breeding season begins in late spring and early summer, although some breeding takes place throughout the year

  • Mating rituals: A male approaches a female and attempts to embrace her with his forelegs or rub and sniff her body. If she is receptive, the two roll and frolic; if not, she will push him away. Copulation is preceded by vigorous play - chasing, swimming, diving, twisting, cork-screwing, and lunging.

  • Number of offspring produces at a time: as many as five young in a litter

  • Any unique characteristics of their mating: the two roll and frolic; if not, she will push him away. Copulation is preceded by vigorous play - chasing, swimming, diving, twisting, cork-screwing, and lunging. 

• Development

  • Stages of development

Mothers give birth to furred and blind cubs in an underground den near the river shore and fishing sites. Pups grow rapidly and emerge from the den at about 2 months of age. Giant otter pups eat solid food at three to four months. Clawless otters open their eyes at about 40 days, and first swim at nine weeks. They take their first solid food at about 80 days. All freshwater otter pups stay with their mothers for a year, until the next litter is born.

• How old before sexual maturity

Observations of captive individuals suggest that giant otters of both sexes reach sexual maturity at between 2 and 3 years of age.

• Activities and environment of stages

Giant otters build dens, which are holes dug into riverbanks, usually with multiple entrances and multiple chambers inside.

• Difference between males and females

Adult male total body length ranges between 1.5 to 1.8 m, while females are marginally smaller at 1.5 to 1.7 m.

• Causes of death

  • Predation: It doesn't have any natural predators. Jaguars and Pumas  may occasionally take inattentive animals. The altricial young are sometimes taken by the same predators, and may also fall victim to black caiman and anaconda.

  • Sexual Competition: none, because they mate for life

  • Disease: kidney stones, tooth decay, and cirrhosis of the liver.

  • Other causes:  pollution, habitat destruction, and persecution - commercial and game fisheries see otters as competition for resources.

• Competition

  • Inter-species – within the species:They don’t compete with each other

  • Intra-species – with other species: It can compete with other species such as the black caiman, the neotropical river otter.

  • What do they compete over: They compete over food.

  • Affect of invasive species: No invasive species affect giant otters

• IUCN Rating

  • What is the rating?: Endangered (3.1)

  • Population: 2,000 to 5,000 total in the wild.

  • Population Trend: 10-percent per annum increase in population abundance

• Impact of Humans

  • What impacts have occurred: habitat degradation, river contamination due to mining and agriculture, overharvesting of fish, and hunting for its skin.

  • Potential Future impacts: When mining and deforestation occur in an area, the otters can be directly affected because the river banks they live on and depend on can be badly destroyed. Other indirect impacts are also likely to harm them. There are usually less fish to feed on, and harmful contaminants such as mercury are flushed into the river.

  • How long have humans been interacting with species: they became the target of the international pelt trade in the 1940s, and by the early 1970s had been hunted to the brink of extinction.

  • Efforts being made to minimize impacts: research, population monitoring, and the preservation of fish stocks in the river to make sure the otters have plenty to eat