The otter

The otter

The otter :

The otter or otter belongs to the family of weasels, under the order of [[what is meant by a carnivorous animal|carnivores] which falls under the sect of mammals, under the division of chordates, which belongs to the animal kingdom.

With regard to otters, they are small to medium-sized animals with short legs, long and slender bodies, a long tapering tail, and their body – except for the feet and snout-is covered with soft and dense fur, and they are characterized by possessing developed senses and sharp instincts that help them hunt. they are also semi-aquatic animals that get their food from water and are able to live in marine and freshwater environments.

Otter sex :

The genus otter (Lutra) includes the following otter species:

European otter:

(Lut: Lutra Lutra) ((european: European otter).. The European otter is characterized by being nocturnal in general, and loving solitude, but it may live in a family, and its diet consists of fish, crustaceans, amphibians, reptiles, birds, eggs, insects, and worms.

Otter feels the nose:

(Lut: Lutra Sumatra).. The hairy-nosed otter that lives in Southeast Asia is a rare and endangered species; since there are many threats to it within the limits of its natural habitat, so it is now being preserved and multiplied under the supervision of humans outside its habitat until its numbers stabilize and it becomes possible to transfer it to nature reserves.

Genus of spotted-necked otter :

Hyd (hydrictis) ((hydrictis maculicollis).

Individuals of this species are spread throughout Africa, specifically south of the Sahara Desert, and despite the wide geographical range that forms the boundaries of its habitat, the numbers of individuals of this species are very small; due to the increased pollution, and the loss of habitats in which it lives, and because it is very demanding in terms of the environment suitable for its living, it lives only in areas where fresh water is available throughout the year, and does not live in marine or coastal environments that contain salt water, on the other hand, the areas of its presence must contain dense vegetation; because it provides it with a cover that protects it from predators during rest, and gives it a safe place to build dens that are Usually equipped with an entrance accessible from underwater.

Periodic otter sex :

. Lutrogal, lutrogal persicillata.
Individuals of this species are widespread throughout South Asia and Southeast Asia, and its presence has been confirmed in both: Pakistan, India, Nepal, Bhutan, Bangladesh, southwestern China, Myanmar, Thailand, Vietnam, Malaysia, Indonesia, and Brunei, but in the Middle East its presence has been confirmed only in Iraq, where members of this species are found as a partial community, and although soft-furred otters live mainly in the plains, they can also live in semi-arid areas of northwestern India, the Deccan plateau, it is worth noting that soft-furred otters take refuge in large rivers and lakes, estuaries and peat swamp forests, mangrove forests, rice fields in search of food.

Genus of new world otters :

The genus of the New World Otter ( Lontra) includes the following species:

Northern Rivers water cans: (Lontra Canada)

At (northern: northern river otter) [- to use it as a dwelling place, these animals avoid water bodies with sloping shores consisting of sand and pebbles.

Southern river otter: (scientific name: Lontra provocax)

The southern river otter lives permanently and came near fresh water, where it lives near rivers and May whose banks have vegetation, in inland lakes, and near the rocky coastal areas of both Argentina and Chile, and its diet consists mainly of May fish, but it also hunts crabs, mollusks, birds, and among the problems faced by the southern river otter that has led to a decrease in its numbers: poaching, habitat loss, in addition to the presence of imported salmon that compete with local fish, especially salmon moving so fast that the otter cannot catch it.

Otter of the rivers of the new tropical territory: (scientific name: Lontra longicaudis)

The Neotropical River Otter is also known as the long-tailed otter because the length of its tail may be equal to or exceed the length of its body. Individuals of this species live throughout South America except for Chile and very arid regions, where their range extends from Mexico South to northern Argentina, preferring to live in warm temperate climates, rainforests, evergreen forests, rocky shores, coasts, and it is important for him to be constantly near Salt and fresh water where he spends most of his time inside the water.

Sea otter: (scientific name: Lontra Felina)

The Marine Otter lives along the Pacific coast stretching from northern Peru South through the coast of Chile to the south of South America, as well as some isolated areas of Argentina. The sea otter is distinguished from the rest of the species of the genus of new world otters by the fact that it lives exclusively in the seas, cannot live in freshwater, prefers areas with strong winds, dense seas containing many species of rockfish, mollusks, crustaceans. The sea otter spends most of its time in the water, but it may sometimes resort to caves with rocky outcrops, especially during the breeding season, because they provide it with protection from predators and contain many preys, and it is believed that sea otters do not live on the Atlantic coasts of Patagonia, because its beaches are sandy and it prefers rocky beaches in particular.

Genus otter wing tail :

The genus of the wing-tailed otter, which is characterized by a flat wing-like tail, includes one species, the giant otter, known scientifically as (Pteronura Brasiliensis), which is known as the most widespread species of otters, but hunting operations have turned it into an animal close to extinction, reaching a length of about 170 cm. The giant otter lives in rivers, lakes, and swamps of South America, where it was found in the southeastern part of Peru except for areas close to the steep Andes mountains, and lives in large family groups that include parents who are related together throughout life, and their offspring, and although the members of the group often protect their areas from intruders, they may accept the joining of unrelated individuals, and giant otters are characterized by the presence of markings on the neck that distinguish each individual from the other, they are diurnal animals, very noisy, and have very popular with tourists who come to watch them in the reserves.

Genus of small-clawed otter :

The genus of the small-clawed otter (Aonyx) includes the following species:

African clawless otter: (scientific name: Aonyx Capensis)

The African clawless otter is the third largest genus of otters, and it lives mainly in freshwater, but it may reach marine habitats in its wanderings, and then return to freshwater to wash the salt from its body, it can also be found in towns and cities, and it can live in polluted rivers. This species is characterized by not having claws, and the membranes covering its claws are reduced, however, it has a high ability to hunt even in dark waters thanks to its long mustache hairs that sense the movement of prey, and thanks to its large molars capable of crushing crabs and lobsters, it also lives on frogs, fish, insects, and the African clawless otter is active at dusk. it is usually a solitary animal, but it may live within a family consisting of a mother and her offspring-rarely the father – in seasons when hunting is available.

Congo clawless otter: (scientific name: Aonyx Congicus)

The Congo otter lives in the Congo River Basin including the Republic of the Congo, the Democratic Republic of the Congo, Equatorial Guinea, Gabon, Southern Cameroon, Southern Central African Republic, and northern Angola, and its range extends east to the forests and wetlands of Rwanda, Burundi, and Uganda, where it is widespread in rainforests, lowland swamps, felled swamp forests, and some extended rivers within its range.

Oriental small-clawed otter: (scientific name: Amblonyx Cinereus)

The Oriental small-clawed otter is also known as the Asian small-clawed otter, it is the smallest species of otter in size, it is widespread in southern India, southern China, Southeast Asia, Indonesia, the Philippines, spends most of its time on land, prefers to live in shallow waters rich in good food sources, areas with moderate to low vegetation, however, it is also adapted to live in humid coastal tropical lands, mountain streams, rivers, swamp forests, freshwater, rice fields, mangrove forests, lakes, streams, and reservoirs, canals, drainage channels, tidal zones that are located within the This animal is characterized as a sociable and intelligent animal, as it shares habitats with the European Otter, the smooth-furred Otter, the hairy-nosed otter, and the eastern otter is characterized by its superior ability to adapt to climatic and dietary changes.

Genus of marine otter :

The genus of the sea otter (Enhydra) includes one species, the Marine otter scientifically known as (Enhydra lutris), whose skin is covered with fur and is the densest of all mammalian species, which compensates for the absence of the fatty layer that is usually found under the fur, which helps mammals to tolerate the cold, and sea otters are characterized by living in groups consisting of one genus and spend their time floating on the surface of the sea, or diving in search of oysters, crabs, and sea urchins, and it is rare to the beach.

Sea otters previously spread from Mexico to Alaska and even Japan, and then their numbers decreased until they were almost extinct, but their numbers increased in time, and they can currently be found in Russia and California, and they are also found in large numbers in Alaska, however, they are still exposed to many dangers, including the danger of hunters looking for fur, predators such as killer whales, and toxins carried by water.

Otter characteristics :

Body composition :

All otter species are characterized by their brown color close to chocolate except for the chin, throat, and abdomen, where these areas appear in a pale cream color, otters have a long, sinuous body covered with two-layer fur; an outer layer containing long waterproof hair, and an inner insulating layer composed of air, they have a flat head and small ears, a wide snout surrounded by long, stiff hair, otters also have a long, thick tail that helps them swim, short, strong legs, feet ending with five fingers separating between them are membranes in most species.

Size :

There are Otters of different sizes, the largest of which is not the weight of the giant otter, which is between 1.5-1.8 meters long, the smallest and lightest is the small-clawed eastern otter, whose body length is 90 cm, and its weight does not exceed 5 kg, and the heaviest species is the sea otter, where males weigh 41 kg.

Senses :

The following is information about the senses of otters:

Hearing aids :

Sea otters have a strong sense of hearing, which has a fundamental role in sensing danger.

Sight :

It is the most important sense in hunting, and the otter is able to see clearly thanks to the ability of the lens of the eye and the cornea to correct the refraction of light as it passes between water and air, and the vision of the sea otter is equal in terms of clarity inside the water or in the air if sufficient light is available, but in dim light, the vision of the sea otter in the air is clearer.

The touch:

The otter brain receives sensory information related to touch from several areas of the body; namely:

Front paws:

Some species of otters, including clawless otters, and marine otters rely on the front paws as tactile receiving organs during their search for food, so the parts of the brain that receive sensory information related to touch from the front paws are large in size.

The mustache:

At the base of the otter mustache hair, there is a network of nerves that transmit sensory information related to touch to the brain, and this part of the animal is also sensitive to underwater vibrations.

The mouth:

Some species of otters such as river otters, and giant otters use the mouth as a tactile receiving organ during their search for food, so the areas of the brain that receive sensory information related to touch from the face are large in size compared to their size in other species.

Sniffing:

Otters have a keen sense of smell, which is the most important sense in communication between otters, especially with regard to territorial zoning, determining the readiness of members of the opposite sex to breed.

Otter behaviors :

Otters are characterized by being nocturnal animals, they are also very sociable and live in groups called a herd or rafting, they are curious animals and love to explore, they love to amuse, they practice wrestling, chasing the tails of some of them, and sliding from water dams.

Body adaptation :

Here are the most important adaptations of the otter body:

  • There are both eyes and nostrils on the top of the head so that the otter can see and breathe even if its body is completely immersed in water.
  • Mustache hairs are characterized as highly sensitive, which helps them to locate prey in extreme darkness when visibility is almost non-existent.
  • The ears are small in size and protected by a valve that closes when the animal enters the water to prevent water from getting into the ear.
  • The hind legs are longer than the front legs, which helps him to run fast on dry land.
  • The streamlined shape and webbed feet help the otter swim into the water with agility comparable to the speed of a seal or a dolphin.
  • The otter uses its paws for paddling while swimming on the surface of the water but tightens its legs to its body when it is underwater, releasing them only when there is a need to change the direction of swimming, and to increase the speed of its rush the otter bends the back of its body up and down.
  • The Marine otter is characterized by a high metabolic rate, which exceeds that of mammals similar to it in size that live on land, and it is a kind of adaptation to compensate for the Heat lost by the body while swimming in cold water due to the increase in body surface area relative to size, which is extremely important for maintaining a stable internal body temperature.

Behaviors for survival :

Otters show behavioral adaptations that help them to live and survive in their environment, an example of this is the eagerness of otters to clean their fur by biting and rubbing it with rocks, grasses, and tree trunks; in order to protect it from parasites and keep it in good condition; to fulfill its role as an insulating layer of water, and so that otters can get their food from oysters, they open the hard shell of oysters in an innovative way, they put a rock on their chest while floating on their back in the water, and start knocking the shell of oysters on it so that they can open them.

Movement :

The otter is able to swim by moving its body up and down, swinging its tail back and forth, and to increase its speed it starts moving its hind legs, which are characterized by the presence of membranes separating the fingers, and the otter is good at swimming close to the surface of the water, diving deep and spinning, and it can also swim on its back or on its side, and when it feels tired it can simply float on the surface of the water for a short time, and then returns its activity.

Otters are good at diving, and river otters can stay underwater between 6-8 minutes, while sea otters usually stay underwater between 52-90 seconds, and their diving period can increase when they feel in danger, as the greatest depth at which sea otters have dived is about 97 meters, although they usually dive to a much lower depth in search of their food, and sea otters that live in Alaska usually dive to a depth of 40 meters, and it is also rare for sea otters in California to be found in waters where its depth is more than 20 meters.

Communication :

Otters communicate among themselves in several ways, including:

Sounds: otters communicate by making a variety of sounds such as barking, screaming, whistling, rumbling, howling, and other sounds.

Smell: river otters secrete an aromatic odor through a pair of glands located near the base of the tail, and to spread the smell, they rub their bodies with tree trunks and leaves and roll over the parts of deciduous plants on the ground; in order to determine their territorial areas, communicate information about the identity of individuals among themselves, distinguish them in terms of sex, and mating ability.

Feces: otters deliberately defecate in prominent places to prove their presence and identify themselves by spreading the smell of their feces, as the smell of an individual’s feces has a distinctive feature that is not similar to the smell of another individual’s feces.

Stacking: otters establish their presence somewhere by accumulating small piles of sand, gravel, grass, or mud that have been rubbed into their body, and this type of behavior can be understood as evidence of their presence.

Sleep :

Otters that live in fresh water sleep on the ground or inside Burrows, and one individual can have several places to sleep, but sea otters float on their backs on the sea surface if they want to sleep, and fix themselves with seaweed so as not to drift away, so they are keen to fix themselves with dog algae before they go to sleep and for the same purpose one of the otters specific places to sleep collectively.

Otter food :

Most of the otter’s diet consists of fish, especially Eels, in addition to amphibians, River crabs (freshwater crayfish), waterfowl, and small mammals, as the otter begins hunting with sunset, which is the time when many species of fish become lethargic and easy to catch, and depends in hunting on the sense of sight and on the mustache hair that enables it to sense the vibrations caused by the movement of fish in the water, and when the otter catches a small-sized fish, it is expected to eat all its parts, and if the fish is large, he will eat enough meat and leave what he needs in excess for other animals to eat.

Most species of otters grab their prey using their jaws, while the three species belonging to the genus of small-clawed otter grab prey using the paws of their forelimbs.

Places where the otter lives :

Otters live all over the world except Australia, Antarctica, and they can live in all environmental environments except mountains, deserts, and polar regions, and it is worth noting that all types of otters-except marine otters – can live both in water and on land, where they live on rocks, driftwood, or in abandoned burrows built by other animals such as beavers.

The life cycle of the otter :

The average life span of an otter :

Otters live between 10-15 years, and about 32% of river otters die during their first year, and 54% of them during the second year when they begin to rely on themselves, and then the percentage decreases after that when the puppies become more powerful and able to defend themselves, however, less than a quarter of female puppies manage to live until they reach adulthood, despite that the record of the greatest age reached by the otter to more than 20 years in zoos.

Reproduction of Otter :

Sea otters differ from other species of otters in the way they reproduce, they are the only species in which the female’s gestation period is 5 months, and they are also the only species in which the female gives birth while she is in the water, in contrast, the gestation period of small-sized species of otters does not exceed two months, after which the females lay between 1-5 puppies – often the number of puppies is two-inside the dens in which she lives.

A female otter can give birth at any time of the year, and newborn otter puppies weigh 128 grams for small-sized species, and 2.3 kg for marine otters, and newborn puppies are pink in color, and completely weak as they depend on the mother’s care for them, and the puppies remain with their eyes closed until they reach the first month of their life, and begin to swim when they complete their second month, it is worth noting that female otters keep the father away after the birth of the young, however, the father may return in some species after several weeks to help the mother take care of the young, and begin too young otters become self-reliant when they complete their first year and reach adulthood between the ages of 2-5, where they can start having puppies.

The importance of the otter :

Otters are one of the main species in life, because they play a pivotal role in preserving the communities in which they live, and preserving the ecosystem to which they belong, as they help along the Pacific coast to control the numbers of sea urchins, as sea urchins prevent the dog Moss forests from increasing their numbers, in addition, they promote the growth of seagrass meadows in California, and the increase in the numbers of otters in the Gulf of Alaska National Park has led to a more diverse ecosystem.

The dangers faced by the otter :

Pollution :

Otters become infected with diseases that can lead to their death as a result of the accumulation of toxins in their bodies when they eat prey poisoned by pollutants thrown by humans in the water bodies in which they live, and these pollutants include chemical toxins used in agriculture and industry such as heavy metals, including mercury, lead, and pesticides.

Predation :

Vulnerable individuals of otters such as puppies and very old otters are exposed to predation by some animals on lands such as wolves, birds of prey, and reptiles, while marine otters are more susceptible to predation by the great white shark in California, killer whale, grizzly bear, coyote, and a bald eagle that feed on young otters in Alaska. The Otters of the Northern Rivers living along the Gulf Coast are vulnerable to predation by crocodiles, black bears, various species of felines, and canids.

Diseases and parasites :

River species of otters are exposed to many diseases such as tooth decay, kidney stones, and cirrhosis of the liver, and they are also infected with some parasites, such as Trematodes, roundworms, tapeworms, ticks, as for marine otters living in California, they are exposed to fungal, bacterial, and parasitic infections, and among the parasites that infect this animal, gondial arch parasites, whose eggs are transmitted from invertebrates to otters, and infect them with encephalitis, which may lead to their death, and myxocytic parasites, which is a primary parasite that lays its eggs in some sources of Otter food, which leads to encephalitis, and spiky-headed worms which transfer their eggs from the feces of seabirds to invertebrates that otters feed on, and when the worms reach Her intestines perforate her and cause her peritonitis disease.

Habitat destruction :

Otters are selective animals in terms of their choice of habitats in which they live; they need coastal areas full of dense vegetation to be able to live and find a safe haven to sleep and reproduce, but increasing agricultural development has led to some negative changes such as: Removing vegetation from river banks, changing the shape of rivers to become straighter, building artificial barriers to prevent flooding, drying ponds and wetlands (marshes), which led to a reduction in suitable habitats for otters. in the tropics, the increased agricultural activity resulting from an increase in population, overgrazing, and deforestation led to soil degradation and erosion, increased silt deposition in rivers, and an irregular supply of water to rivers, which in turn affected the natural flood cycle, formed barriers to the movement of otters and caused significant changes in their habitats.

Poaching :

Otters are poached for fur, and they are also killed by humans for their role in the consumption of Fish and crustaceans in fish-breeding farms in Europe, and in aquaculture projects both in Asia and Africa.

Climate change :

Climate change leads to changes in environmental conditions such as irregular temperatures and precipitation, which affects the ecosystem, such as the abundance of food, or the quality of predators, and even diseases and parasites that may affect it, forcing otters to survive and endure new conditions, or move to other places in search of better conditions, noting that the degree to which otters are affected by this type of changes varies from one individual to another depending on the degree of sensitivity of the individual, and his adaptability.

Facts about the otter :

Here are some facts about otters:

  • Otters do not have a fatty layer under the fur; therefore, their fur is thicker than that of any other animal, as it consists of a large number of hairs, up to one million hairs per square inch.
  • Otters eat up to a quarter of their weight in food per day.
  • The capacity of the lungs of otters exceeds the capacity of the lungs of any terrestrial mammal similar to them in size by 2.5 times.