Turkish Journal of Fisheries and Aquatic Sciences
2013, Vol 13, Num, 2 (Pages: 249-259)
Vertical Distribution and Feeding Ecology of the Black Scraper, Thamnaconus modestus, in the Southern Sea of Korea
2 Pukyong National University, Department of Marine Biology, Busan 608-737, Korea DOI : 10.4194/1303-2712-v13_2_07 Viewed : 3986 - Downloaded : 3403 We investigated the vertical distribution and feeding ecology of the black scraper, Tamnaconus modestus, in the southern sea of Korea in the spring of 2009, 2010 and 2011 using otter trawl for 60 min per site. Fish abundance was significantly related to the basis of depth and temperature. Thamnaconus modestus occurred at depths ranging from 80 to 120 meter waters having temperature higher than 12°C. We found that 87% of the total catch were obtained at the depths between 80 and 120 meters (58% and 29% from 80–100 and 100–120 meters respectively). The total length of captured individuals ranged from 10.6 to 38.7 cm. Individuals captured at deeper were significantly larger than those from shallower sites. Diverse prey organisms, including algae, amphipods, gastropods, ophiuroids, and cephalopods, were found in T. modestus stomach. The main prey items in IRI value belonged to four groups: hyperiid amphipods, gastropods, ophiuroids, and algae. The fish showed ontogenetic diet shifts. In general, individuals in smaller size (< 20 cm) shifted their diets from vegetative food sources to animal ones when they reach the size bigger than 20 cm. Food diversity increased with fish size. Our findings suggested that T. modestus vertical distribution varied with depth and that fish showed ontogenetic diet shifts Keywords : Tamnaconus modestus, Southern sea of Korea, distribution, stomach contents, PCR