Publications by authors named "Hyung-Kyu Nam"

The body condition of a snake species provides important physiological, morphological, and ecological information that elucidates its habits, life cycle, and competitive relationships. We measured the body size and condition of the wild Gloydius ussuriensis population in South Korea from 2018 to 2022, analyzed the degree of intraspecific niche overlap, and identified the geographic and climatic factors affecting their body condition. We found that the females were longer than the males.

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In this study, we analyzed the complete mitochondrial genome of using Illumina and Pacbio next-generation sequencing. The total length of the mitogenome was 18,170 bp and contained 13 protein-coding genes (PCGs), two ribosomal RNAs, 22 transfer RNAs, a non-coding control region, and two repeat regions. The order of the genes and genome structure were the same as those in a previous publication in other Cuculidae species.

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Rice fields are important habitats for a variety of water birds, and their importance is increasing with the destruction of natural wetlands. This study was conducted to understand the foraging strategy of the black-faced spoonbill, an internationally endangered species, in rice fields. To achieve this objective, the feeding success rate of black-faced spoonbills in rice fields was analyzed considering the species' feeding behavior, environmental factors, and external factors.

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Understanding the geographic distribution of species is crucial for establishing protected areas. This study aimed to identify the preferred habitat environment of South Korean herpetofauna using distribution point information, providing the information necessary to protect their habitat by establishing a species distribution model. We found that climate variables in the region where 19 amphibians and 20 reptiles were distributed correlated with the altitude, suggesting that altitude had a major influence on their distribution.

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Approximately 58 shorebird species, including endangered and threatened species, use various habitats while traveling on their long-distance migratory routes in the East Asian-Australasian Flyway (EAAF). Coastal rice paddies in midwestern Korea, which are located in the EAAF, serve as inland wetlands and provide important stopover sites for long-distance migratory shorebirds. We studied how shorebird population density is affected across periods, time since habitat formation, and field type, at the rice field scale.

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Many bird species rely on the ecological functions of rice field habitats (e.g., paddy, levee, road, and ditch).

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Pesticide use is known to have a negative impact on the habitat use of birds. The decomposition of residual pesticides causes a drastic decrease in the biomass of wildlife food sources, indirectly affecting the ecosystem. In this study, we investigated the effects of pesticide use on the distributions of grey herons () and great egrets () in rice fields in the Republic of Korea.

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Successful refueling at staging sites is essential for the survival and reproduction of migratory birds. Understanding their staging ecology is therefore crucial for the conservation of migrant species. Rice fields in the mid-western region of the Korean Peninsula serve as staging habitats for the black-tailed godwit ().

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Some seabirds commonly use artificially reclaimed lands, which are frequently located next to mainland environments, for breeding. Nest predation risk caused by birds or mammals from the mainland has negative influence on fitness-related costs and distribution of seabirds. Here, we sought to link potential factors, specifically those related to nest predation and nest environment, with breeding performance and colony movements of the Saunders's gull (Saundersilarus saundersi), a vulnerable species, on a large reclaimed area (1350 ha) in Incheon in Republic of Korea.

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