Abstract
A total of 5,885 fishes belonging to 53 taxa in 27 families were caught during a monthly seine survey (August 2008 to July 2009) in a seagrass Zostera marina bed off Ikuno Island, Hiroshima Prefecture, central Seto Inland Sea, Japan. The numerically dominant species (% in number) were Rudarius ercodes (21.5%), Sebastes cheni (16.9%) and Favonigobius gymnauchen (12.3%) and the weight-based dominant species (% in weight) were S. cheni (15.8%), Takifugu pardalis (10.4%) and Ditrema temminckii pacificum (10.1%). The mean number of fish species was lowest in February (7.5±1.7/100 m2) and highest in September (16.5±1.3/100 m2). The mean fish abundance fluctuated from 25.0±5.8/100 m2 (February) to 365.8±69.4/100 m2 (October). The mean fish biomass varied between 115.5±71.8 g/100 m2 (February) and 672.6±485.0 g/100 m2 (June). Syngnathus schlegeli, D. temminckii pacificum, F. gymnauchen, Acentrogobius pflaumii, R. ercodes were collected throughout the 12 months surveyed. Sebastes cheni, Hypodytes rubripinnis, Gymnogobius heptacanthus, T. pardalis were collected in 11 months and Pseudoblennius cottoides and Tridentiger trigonocephalus were in 10 months. Fish fauna was more diverse from spring to autumn when sagrass shoot density was high and leaf length was long.
