Endangered otters find refuge on artificial islands as Korean rivers face threats

The Eurasian otter, a beloved symbol of healthy river ecosystems, is facing an endangered status in South Korea due to a combination of factors including river pollution, development, and habitat degradation. Once a common sight, these top predators, known for their strong jaws and sharp teeth, are now classified as 'Near Threatened' (NT) by the IUCN and are protected as a Natural Monument and a Class 1 endangered wild species domestically.

Otters are crucial indicators of river health, preying on fish, crabs, frogs, and small mammals. Recent studies even highlight their role in controlling invasive species like the American crayfish. However, human activities pose significant threats. River maintenance projects often involve clearing riverbanks of vegetation like reeds, which otters rely on for resting and shelter. The construction of concrete embankments and artificial structures also disrupts their movement, forcing them to cross roads where they risk becoming victims of traffic accidents (roadkill).

Discarded fishing nets and traps present another deadly hazard. The curious nature of otters leads them to become entangled in this abandoned gear, often resulting in drowning. To combat these threats, conservationists emphasize the need for a holistic approach that goes beyond individual protection. Efforts are underway to restore the natural integrity of river and wetland ecosystems, ensuring safe passage and habitats for otters.

One such initiative, part of the World Wildlife Fund's 'Any Stay' campaign, involves creating artificial "otter islands" in reservoirs. An example is the 'Mudongje' reservoir in Mudeungsan National Park, Gwangju, where a specially designed island provides a safe place for otters to rest and defecate. These islands are constructed with natural materials, mimicking rocks and burrows, and are monitored by motion-sensor cameras to track wildlife activity. These efforts have shown promise, with the first confirmed sighting of otters using an artificial island recorded in February.