Daegu Suseongmot Dungjiseom Overrun by 500 Freshwater Cormorants... Suseong District Office Takes Drastic Measures

Tree Death Caused by Acidic Excrement

Nest Removal and Tree Washing, etc.

Daegu Suseong District Office has established a five-year long-term plan to restore the ecosystem of Dungji Island in Suseong Lake, which is suffering damage due to the collective habitation of freshwater cormorants, and will implement systematic management according to ecological stages.

Dungji Island in Suseong Lake, a habitat for migratory birds in downtown Daegu, has recently seen a rapid increase in freshwater cormorants that have become resident birds over the past three years. This has led to the island becoming a collective breeding ground, disrupting the ecosystem of migratory birds in Suseong Lake. The strong acidity of their droppings is causing trees to wither, resulting in severe pollution of the entire island.

The appearance of Dungji Island in Suseong Lake after the Suseong District Office of Daegu drove away the cormorant flock.

In 2022 and 2023, drastic measures were taken, including nest removal, tree washing using firefighting helicopters, installation and spraying with high-pressure water devices and sprinklers, installation of bird repellents, and ultrasonic deterrents.

However, around March, when the breeding season begins, 400 to 500 freshwater cormorants returned to Dungji Island in January, built 62 nests for laying eggs, and the island turned white again from droppings.

Accordingly, at the end of last month, Suseong District Office removed 62 nests before the breeding season, installed 40 predator models (eagle models), pruned branches, washed trees and Dungji Island polluted by strongly acidic droppings, and continuously disturbed the habitat through ongoing monitoring and observation to fundamentally block access to the island. Currently, no freshwater cormorants are collectively inhabiting Dungji Island, and fewer than 10 birds stay briefly during the day in Suseong Lake before moving elsewhere at night.

In March, during the breeding season, soil acidity on Dungji Island will be measured, followed by soil neutralization work. Hardy woody plants such as forsythia will be planted to improve soil pollution and the environment. Even after the breeding season, continuous monitoring and observation will be conducted to maintain long-term management.

This approach follows the “Freshwater Cormorant Collective Habitat Management Guidelines” prepared by the Ministry of Environment in July 2022, which regulates breeding site formation and population control through non-lethal methods based on the freshwater cormorant’s habitat habits and ecological stage-specific management methods.

Freshwater cormorants are top predators among birds, consuming up to 7 kg of food per day. They typically lay 3 to 5 eggs per breeding season and have an average lifespan of 15 years.

They show strong site fidelity by returning to existing breeding sites upon successful breeding and tend to collectively inhabit remote marine uninhabited islands or islands and watersides within freshwater systems that are difficult for humans to access, requiring long-term and systematic management.

Various migratory birds such as herons, water rails, and mallards that used to live on Dungji Island in Suseong Lake have been displaced by freshwater cormorants, and only a few remain in Suseong Lake today.

Kim Dae-kwon, head of Suseong District Office, said, “Dungji Island in Suseong Lake, beloved by Daegu citizens, is becoming desolate and dying due to the collective habitation of freshwater cormorants. It is a time when active human intervention is necessary for the coexistence of diverse ecosystems. We will systematically control the population according to habitat habits and ecological stages to restore the beautiful Dungji Island and regain ecological balance.”

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