99% of Plastic Detected in Seabird from Chilbaldo, Sinan-gun
Mistaken for Food or Swallowed Along with Prey
A study has revealed that most bird species living in the western sea of Korea are threatened by marine debris such as plastic. Ninety-nine percent of the birds ingested plastic waste, with young birds swallowing more plastic debris than fully grown adults. It was found that 63% of the young birds had plastic waste accounting for more than 0.1% of their body weight.
On the 15th, Dr. Kim Miran of the Seabird Research Institute and colleagues published a paper titled “Marine Debris Ingestion by Adult and Juvenile Korean Swifts” in the latest issue of the international journal Marine Pollution Bulletin.
The Korean Swift, with a dark brown body and about 20 cm in length, is a common summer migratory bird distributed across Korea, Japan, China, Taiwan, Singapore, and Indonesia. Notably, about 70% of the world’s swifts breed in Korea. The representative breeding sites, Chilbaldo and Guguldo in Sinan, Jeollanam-do, have been designated as natural monuments.
According to the paper, among 146 swift carcasses found dead due to entanglement in invasive plants such as Sesbania cannabina on Chilbaldo, Sinan-gun, Jeollanam-do, in 2013-2014, plastic debris was detected in 145 cases (99.3%). This rate is higher than that of the Northern Atlantic’s Northern Fulmar (87.5%) and the Antarctic Wilson’s Storm Petrel (75%).
The plastic debris found in the swifts from Chilbaldo had an average weight of 51 mg and an average length of 4 mm.
It was also notable that more plastic debris was detected in the bodies of juvenile swifts than in adults. Adults ingested an average of 15.2 pieces per bird, while juveniles ingested 24.3 pieces per bird. The research team reported that 63% of juveniles and 24% of adults had plastic debris accounting for more than 0.1% of their body weight.
Regarding this, the researchers explained, “It appears that plastic debris accumulated in the adult birds’ bodies decreased during the process of feeding the juveniles.”
Thread-like plastic debris was most commonly found in adults, whereas fragment-shaped plastic debris was most common in juveniles. Additionally, adults ingested the most green plastic debris, which is presumed to be fishing nets.
Seabirds often mistake small plastic pieces for food or swallow them along with prey. During the breeding season, they sometimes feed plastic to their chicks, mistaking it for food. Small-bodied seabirds are known to suffer more severely because they cannot regurgitate plastic.
In fact, in March, the international life sciences journal Nature Ecology & Evolution published research showing that seabirds ingesting plastic suffer adverse health effects such as antibiotic resistance and changes in gut microbial communities.
Moreover, as more birds use debris to build nests, there is growing concern about increased safety risks. Researchers from Poznan University of Life Sciences in Poland and others published these findings in July in the Proceedings of the Royal Society B: Biological Sciences.
After analyzing a total of 75 research papers, the researchers revealed that, excluding Antarctica, a total of 176 species including ducks, raptors, gulls, and cormorants use waste materials to construct nests across all continents.
© The Asia Business Daily(www.asiae.co.kr). All rights reserved.
