20+ Interesting Facts About Otters

1. Otters are semi-aquatic mammals of the weasel family. They include 13 living species present in all continents except Australia and Antarctica.
2. Eleven of the 13 species are known as river otters, present in freshwater habitats like rivers, lakes, and wetlands. The sea otter and the marine otter are the two aquatic species of the Pacific Ocean.
3. The smallest species is the Asian small-clawed otter that can attain 3 kg weight. The sea otter is the biggest with 45 kg weight, while the giant otter (26 kg) is the largest freshwater otter species. 
4. Otters are famous for their playing with rocks. They are social animals and learn this behavior from other otters. Research has proved that playing does not improve their hunting skills, but they do so in the excitement of getting food. (Source)
5. Otter feces, known as spraint, have one of the least offensive odors in the animal kingdom. A jelly-like substance covers the poop, which has a fishy odor because otters consume fish.
6. River otters use a communal area as a latrine. They use this place for social interaction and chatting. This habit increases safety and reduces internal fighting. (Source)
7. Communal latrines in river otters can assist scientists in finding pollution in freshwater habitats. Their defecation can provide more comprehensive information about pollutants in rivers than analyzing water or river sediment. (Source)
8. All otter species are carnivorous. River otters eat prey present in a freshwater habitat, including fish, crayfish, mussels, frogs, and crabs. Sea and marine otters consume sea urchins, fish, shellfish, crabs, and shrimp. Sea otters can also drink salt water, which enables them to live in the sea for several days. 

   

   Otters are expert in hunting fish

   
   
9. Fishermen have been using otters to catch fish for nearly 1,500 years. However, this practice is now present only in Bangladesh. (Source)
10. Crocodiles and alligators are the main threats to river otters. Birds of prey and large carnivores can hunt them on land. Sharks and killer whales are the primary predators of sea otters.
11. Otters are apex predators and can sometimes overcome far bigger animals like young alligators and snakes in their territory. (Source)
12. Sea otters give birth in the water, while other otter species reproduce on land. These mammals usually occupy dens of beavers and other animals for this purpose. There are one to three pups in a litter after a gestation period of two months. The newborns usually remain with their mothers for six months to a year.
13. Otters usually live for 10 to 15 years in the wild. However, they can live for 20 years or more in captivity. 
14. Various otter species have individual feet and claws. River otters have non-retractable claws and webbed digits. Three species of clawless otters (African clawless otters, Congo clawless otters, and Asian small-clawed otters) have very small or no claws. They also have partial webbing on their feet. Sea otters have webbed feet with retractable claws.
15. Otters can remain underwater for several minutes. Sea otters can hold their breath underwater for 5 minutes, while the dive of river otters can last for 8 minutes.
16. Freshwater otters have long and muscular tails that assist them in swimming at high speeds. They also have anal scent glands at the base of their tails. Sea otters are different as their tails are short and less muscular, which they use to take turns while swimming. In contrast to other otters, they also lack scent glands.
17. Unlike other marine mammals, otters lack blubber (thick layer of fat) under their skins. However, their dense and waterproof fur assists them in adopting aquatic habitats. Sea otters have the thickest fur of any animal. Sea and marine otters have longer pelts than other species.
18. Otters have a high metabolic rate and they eat up to 25% of bodyweight daily. If the food is scarce, a male otter may hold pups hostage and take food from its mother (female otter) as ransom.
19. Large-scale otter hunting started during the 18^th Century. Both adult and young otters suffered due to their fur, previously used in expensive robes, hats, belts, and mittens. However, the discovery of silk and the introduction of laws to prevent their extinction reduced this practice. Nowadays, these mammals are hunted by fishermen because they consume a large number of fish. (Source)
20. Hairy-nosed otter is the most endangered otter species. It was considered extinct after the death of the last known animal in 1997. However, researchers rediscovered this otter in Malaysia in 2010. (Source)
21. According to IUCN, five otter species (sea otters, marine otters, giant otters, southern river otters, and hairy-nosed otters) are endangered, and two others (smooth-coated otters and short-clawed otters) are vulnerable. The biggest threats to otters are habitat destruction and pollution.
22. Otters usually do not attack humans. However, they can cause injury if people get close to mothers with pups. Their bites and scratches can be deadly due to the presence of rabies. (Source)
23. River otters primarily use their eyesight and whiskers for hunting underwater. Alternatively, they can also find their prey in water by using their smell. Only a few mammals have this ability. (Source)