|Hundreds of egrets were spotted in a forest of Chinese junipers and hinoki cypresses in Gwangju's Seo-gu in 2012. It is a rare scene in an urban setting. Yonhap|
By Ko Dong-hwan
National researchers have successfully counted the number of egrets in Korea, an important environmental indicator and essential groundwork to monitor the national ecology and the species.
The National Institute of Biological Resources (NIBR) in Incheon said Wednesday the survey of the birds was done March to July from 2018 until this year.
It has revealed there are 34,373 pairs of seven kinds of egret ― grey herons, Eastern great egrets, intermediate egrets, little egrets, cattle egrets, black crowned night herons and Chinese pond herons ― spread across 176 habitats.
The NIBR said the survey was taken "to secure a basic data pool required to protect the country's wetland ecology and manage the birds' habitats." It also has achieved "a major accomplishment in finding the habitats' locations and how many and which kinds of egret live there."
"By this survey, we have learned specific environmental characteristics of egret habitats and their ambient settings," NIBR president Bae Yeon-jae said. "We will use the data to prepare specific measures to protect and manage the birds and their habitats."
|An egret feeds on a fish caught from the Cheonggyecheon stream in Seoul. Yonhap|
The NIBR used geographic information systems (GIS) and on-foot field research to discover the number of different egrets and their nests and the surroundings of each habitat.
The survey revealed that the number of habitats, while distributed rather evenly across the nation, was somehow slightly concentrated in the southeastern region of Gyeonggi Province and the northwestern region of South Chungcheong Province. Grey herons were found in the most habitats, 165, while Chinese pond herons were in the least with seven.
The survey showed the birds have no particular attachment to specific trees. Among the habitats, coniferous forest accounted for 45.5 percent, broad-leaf forest 37 percent and bamboo trees 5 percent.
Egrets, one of the top predators in food chains, provide a critical barometer of wetland health and ecological hazards because they feed on diverse species across various wetlands.
Some 72 types under the egret family have been found across the world, 18 of which have been spotted at South Korean streams, reservoirs, paddy fields and ocean shores as they migrate.