"March Crucian Carp Die-Off in Gongjicheon, Chuncheon Not Caused by Toxic Substances"

Gangwon Institute of Health and Environment Announces Results of Two Additional Investigations
Presumed to Be Caused by Ecological and Physiological Factors During Spawning Season... "Residents Can Be Reassured"

On April 24, the Gangwon Provincial Institute of Health and Environment (Director Shin Incheol) announced the results of a detailed investigation into the mass die-off of crucian carp that occurred in Gongjicheon, Chuncheon in March. The Institute stated that the deaths are presumed to have been caused by physiological and ecological factors related to the spawning season, rather than the inflow of toxic substances.

Gangwon Provincial Institute of Health and Environment conducting additional detailed investigations twice on April 11 and 17 to identify the cause of the mass die-off of crucian carp in Gongjicheon, Chuncheon. Photo by Gangwon Provincial Government

The mass die-off of crucian carp was first reported on March 21. The Institute and Chuncheon City immediately conducted a joint on-site investigation. The initial water quality analysis found no evidence of the inflow of toxic substances such as pesticides, detergents, or heavy metals. It was initially presumed that physical injuries sustained during spawning and ecological and physiological stress were the causes.

However, as sporadic die-offs continued and residents' concerns and complaints persisted, the Institute conducted two additional detailed investigations on April 11 and 17.

Water quality analysis from these investigations, like the initial analysis, found no inflow of hazardous chemicals or toxic substances. While some deterioration in water quality was observed in stagnant sections of the affected area, ecological toxicity tests using water fleas detected no toxic effects.

Choi Jaeseok, Director of the Fish Research Center at Kangwon National University, explained, "Recently, crucian carp in their spawning season have been moving to the midstream area of Gongjicheon in search of spawning grounds. As adult crucian carp engage in spawning behavior, they suffer various physical injuries such as body damage, congestion, scale loss, and fin damage. It is presumed that these injuries, combined with additional physiological stress (such as reduced immunity) caused by sudden changes in water temperature and water quality, led to the deaths."

Shin Incheol, Director of the Gangwon Provincial Institute of Health and Environment, stated, "We believe the ongoing crucian carp die-off in Gongjicheon is due to physiological stress associated with the spawning season," and added, "We hope that this investigation will provide some reassurance to residents who have been concerned about the crucian carp deaths."

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