2020 年 8 巻 p. 59-64
Farm ponds in Satoyama landscapes are important habitats for lentic organisms. However, there is concern about loss of biodiversity in these ponds owing to urbanization and/or abandonment. For conservation planning, species composition and diversity of the aquatic biota should be determined in each pond because of inter-pond differences. We investigated the aquatic fauna in 50 farm ponds in eastern and northern Harima, Hyogo Prefecture, between the 1st and 6th of August 2012. Using a cast net and a D-flame net, we captured 2,146 fish (representing 4 orders, 7 families, and 16 genera or species), and 154 invasive red-swamp crayfish (Procambarus clarkii) in the littoral zones of the selected ponds. The average number of fish species, individual fish and individual crayfish captured per pond, and the range in number between ponds was 3.0; 0-7, 43.0; 0-187, and 6.7; 0-54, respectively. We also measured the total biomass (g) of captured crucian carp (Carassius spp.), invasive largemouth bass (Micropterus salmoides), bluegill (Lepomis macrochirus), and red-swamp crayfish. The average biomass per pond, and the range in biomass between ponds was 221.9; 1.4-2,095.0 g (crucian carp), 116.6; 8.0-390.0 g (largemouth bass), 114.7; 1.0-690.0 g (bluegill), and 92.4; 0.2-760.0 g (crayfish). We suggest that these datasets may be useful for regional aquatic fauna conservation planning and for future academic research on the assemblage structureing assemblages of aquatic organisms.