27 Endangered Otter Families Have Returned to the Han River

Mainly Inhabiting Eastern Han River, Including Seongnaecheon and Jamsil Bridge

A total of 27 otters have been identified as living in the Han River.

Otter. National Institute of Biological Resources

On September 3, the National Institute of Biological Resources announced that, based on genetic analyses of 106 fecal samples collected from 27 locations along the main stream and tributaries of the Han River between January and April, 27 otters are residing in the Han River. The survey revealed that 21 otters inhabit the main stream and 6 inhabit the tributaries. All of these otters are closely related, such as siblings, and there are five family groups that were identified with a parent-offspring relationship.

Specifically, 5 otters were found in Seongnaecheon in Songpa-gu, 4 near Hangang Bridge, 3 near Jamsil Bridge, 3 in Yangjaecheon, and 3 in Jungnangcheon. In terms of gender, there are 16 females and 11 males. This number is nearly twice as high as it was four years ago.

In fact, in March, otters were repeatedly spotted in urban areas of Seoul such as the confluence of Cheonggyecheon and Jungnangcheon, as well as in Anyangcheon. On March 6 at 3 a.m., an otter was observed searching for food among rocks along the water's edge at the confluence of Cheonggyecheon and Jungnangcheon, and six days later, another was captured on camera defecating by the riverside at Anyangcheon.

Yoo Ho, Director of the National Institute of Biological Resources, commented, "The continuous increase of otters in the Han River is a positive sign that the ecosystem is recovering," adding, "We will continue our research, monitoring, and conservation efforts to ensure humans and wildlife can coexist healthily."

Analysis Results of Otter Genetic Information in the Han River. National Institute of Biological Resources

Otters, belonging to the family Mustelidae, are classified as Grade 1 endangered wild animals and are also designated as natural monuments. In the past, otters were commonly found in rivers across Korea, including the Han River. However, due to overhunting for fur and water pollution, their population declined sharply. Particularly in the Han River, otters disappeared after both banks were covered with concrete during the late 1960s as part of the Han River Development Project, and with the construction of the Paldang Dam in 1974, which disconnected the upstream and downstream ecosystems.

However, in March 2016, otters swimming in Tancheon, a tributary of the Han River, were captured on video, prompting the Han River Basin Environmental Office to conduct a survey. In January 2017, a family of four otters was confirmed near Gwangjin Bridge, and subsequent sightings were reported at Bamseom, Godeokcheon, Seongnaecheon, Jungnangcheon, and Hongjecheon. It is believed that improved water quality in the Han River, which secured food sources such as fish for otters, and riverside restoration projects since the 2000s that created natural habitats, have enabled otters to return to the Han River.

The National Institute of Biological Resources is currently conducting research to develop management strategies by analyzing how the urban otter population changes and determining whether their genetic diversity and family ties allow them to withstand disease and environmental changes.

This content was produced with the assistance of AI translation services.