Giant River Otter

Fascinating facts about the Giant River Otter

• At almost two metres long, the giant otter dwarfs every other otter, its body can stretch to 1.8 m (5 ft 11 in) and its tail adds another 70 cm, pushing total length toward 2 m (6 ft). Males tip the scales at 26-32 kg (57-71 lb) and females 22-26 kg, with the heaviest individuals weighing up to 32 kg (70 lb). This size lets it dominate riverine food webs, hunting large fish and defending territories that smaller predators cannot, making it a keystone apex predator in South American waterways.
• Giant otters live in tight-knit family groups that usually number three to eight members, though counts can swell to twenty when several families feed together. Their chatter is a language of its own, Duplaix recorded nine basic sounds, and a 2014 analysis identified 22 distinct adult vocal types.
• Fish dominate the giant otter's menu: a year-long study of scats in Amazonian Brazil found fish in every sample, with Perciformes (cichlids, perch) appearing in 97 % of them and Characiformes (characins) in 86 %. They prefer shallow hunting grounds, water under 0.6 m (2 ft) yields the highest capture success. This razor-sharp visual hunting in shallow water makes the otter a barometer of river health; abundant fish means a thriving ecosystem, while a drop signals trouble.
• Reproduction is a tightly choreographed affair: females cycle every 21 days, being receptive for 3-10 days, then gestate for 65-70 days before birthing 1-5 pups (averaging two). Cubs are born blind, open eyes at four weeks, walk at five, and can swim confidently by 12-14 weeks. They stay with the family until nine months, reach sexual maturity at about two years, and then disperse to start new territories.

Sources

Every fact above was checked against these pages, and kept only where one of them states it.

• Wikipedia

At a glance

About the Giant River Otter

In the waterways of the Amazon basin, giant river otters live fast and loud in close-knit family groups that treat every encounter with the outside world as a team sport. At up to 1.8 metres long, they are apex predators of their river systems, bold enough to mob and drive off black caiman. Nearly exterminated by the fur trade, their survival depends on the integrity of the Amazon they call home.

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