Coastal marine ecosystem plays important role of spawning and nursery grounds for fisheries resources. Yongil Bay is one of major coastal marine ecosystems, which is located in the southwestern East Sea of Korea. Species composition and abundance of marine organism in the Yongil Bay were investigated by season from March to November 2009. Gill net and pot fisheries were used for survey of pelagic and demersal species composition, and collected 106 species, 67 families, and 7 taxa of fisheries resources from the coastal ecosystem. Species were included 2 species in Ascidiacea, 2 species in Bivalvia, 6 in Cephalopoda, 22 in Crustacea, 5 in Echinodermata, 12 in Gastropoda, and 57 in Pisces. Diversity indices (Shannon index, H’) showed seasonal variation with low value of 2.11 in winter, and high value of 2.63 in autumn. Main dominant species were Asterias amurensis, Pleuronectes yokohamae, Siphonalia spadicea fuscolineata, Trachurus japonicas, Sillago japonica, Conger myriaster, Volutharpa ampullaceal, Engraulis japonicus, Asterina pectinifera, and Portunus (Portunus) sanguinolentus that were occupied over 71.5% of total individuals, and 52.9% of wet weight. Seasonal variations of fisheries resources composition were discussed on correlationships with those of environmental factors in the coastal ecosystem of the Yongil Bay in Korea. Those results from this study will provide scientific data and information to develop the ecosystem-based coastal fisheries assessment and management system in Korea.

Abstract
 1. 서 론
 2. 자료 및 방법
 3. 결과 및 고찰
  3.1. 분류군별 계절변동
  3.2. 어업별 종조성
  3.3. 군집분석
 4. 결 론
 참 고 문 헌

• 이재봉(국립수산과학원 독도수산연구센터) | Jae Bong Lee (Dokdo Fisheries Research Center, National Fisheries Research and Development Institute)
• 신영재(국립수산과학원 자원관리과) | Young Jae Shin (Fisheries Resources Research Division, National Fisheries Research and Development Institute)
• 이수정(국립수산과학원 자원관리과) | Soo Jeong Lee (Fisheries Resources Research Division, National Fisheries Research and Development Institute)
• 이종희(국립수산과학원 자원관리과) | Jong Hee Lee (Fisheries Resources Research Division, National Fisheries Research and Development Institute) Corresponding author
• 최영민(국립수산과학원 동해수산연구소) | Young Min Choi (East Sea Fisheries Research Institute, National Fisheries Research and Development Institute)
• 이동우(국립수산과학원 자원관리과) | Dong Woo Lee (Fisheries Resources Research Division, National Fisheries Research and Development Institute)
• 김상우(국립수산과학원 동해수산연구소) | Sang Woo Kim (East Sea Fisheries Research Institute, National Fisheries Research and Development Institute)
• 양재형(국립수산과학원 자원관리과) | Jae Hyeong Yang (Fisheries Resources Research Division, National Fisheries Research and Development Institute)