Otter Conservation Issues

As appealing as these playful little animals are, their lifestyle has created a host of misconceptions, and they are often persecuted by fishermen the world over.

Studies of otter diets have established that these animals do not pose threats to game fish populations.

One study found that North American River Otters prefer slow-moving forage fish, such as suckers, mudminnows and sticklebacks. Some game fish are taken, but make up a small percentage of their diet.

Otters are opportunistic feeders, catching whatever prey is most abundant, and the slowest swimmers. Thus they benefit game fish by removing overpopulated fish species that compete with trout for food.

Other species of otters have also been found to prefer slow fish not desired by fishermen. Yet they are still persecuted in many parts of the world. The Marine Otter, a small otter native to the Pacific coast of western South America, has been so persecuted by fishermen for alleged damage to fisheries that it is now listed as Endangered.

The Sea Otter, protected from previous hunting for the fur trade, began to recover its numbers in the North Pacific, but has recently declined to Endangered status as a result of persecution by fishermen, oil spills and predation by Killer Whales.

River Otters in North America were persecuted by European colonists, many of whom shot them on sight. These animals, described by early explorers as highly visible, bold and playful, became shy, secretive and nocturnal after centuries of persecution and fur trapping.      

Otters are not liked by fish hatchery managers and commercial catfish farmers in the southern USA. State Fish Departments and the Fish and Wildlife Service operate hundreds of hatcheries, raising trout and other fish. Many of these are non-native species that are released far from their natural ranges for the benefit of sport fishermen.

These hatchery programs are regarded negatively by ecologists who have documented that the released fish often cause great damage to ecosystems, outcompeting native fish and introducing diseases. Yet state and federal agencies conduct control programs on otters who raid their ponds.

Rather than screen the ponds from otters, who can hardly be blamed for finding hatchery fish easy to catch, these authorities have had laws changed in many states to allow shooting and trapping of otters that come onto hatchery property.

Eleven species of otters are listed by the 2000 IUCN Red List of Threatened Species, four as Endangered, three as Vulnerable, one as Near-threatened, and three as Data Deficient. This represents a high rate of threat as the otter family, has only 13 species.

Otters tend to be thinly distributed in their ranges, wide-ranging, slow-reproducing and long-lived--all qualities that make them vulnerable to population declines.

Source: Endangered Species Handbook