caa a22 4500 606227881 CHVBK 20210128101200.0 cr unu---uuuuu 210128e20150801xx s 000 0 eng 10.1007/s10641-015-0404-6 doi (NATIONALLICENCE)springer-10.1007/s10641-015-0404-6 Feeding, condition, and abundance of Japanese eels from natural and revetment habitats in the Tone River, Japan [Elektronische Daten] [Hikaru Itakura, Tsubasa Kaino, Yoichi Miyake, Takashi Kitagawa, Shingo Kimura] The rivers and lakes of Japan have had a wide range of shoreline modifications for flood control and stabilization, but the effects of this on the ecology of Japanese eels, Anguilla japonica, is not known. To clarify possible effects of riverbank modifications on yellow-phase Japanese eels in the lower Tone River, Japan, the abundance, condition factor and stomach contents were investigated using 586 eels collected in both revetment and natural shore areas at four sites. Eel abundances and their condition factors were higher in the natural shore areas than those of revetment areas at the three freshwater sites, and the smallest sizes of eels appeared to prefer the natural areas at all sites. The number of feeding eels, their food consumption, and the diversity of consumed prey were also generally greater in the natural shore areas than in the revetment areas. Other differences in diet were observed, such as terrestrial oligochaetes only being eaten by eels at the freshwater river natural shore areas and bivalves being eaten more in the revetment areas of those sites. In contrast, in the brackish habitat eels appeared to be less affected by concrete revetment with wave-dissipating tetrapod blocks. The range of differences found between the freshwater sampling areas suggest that revetment shorelines are used less by eels, particularly smaller eels, when natural shore areas are available, and eels that live near revetment have a lower abundance and diversity of prey to feed on. Springer Science+Business Media Dordrecht, 2015 Anguilla japonica nationallicence Shoreline revetment nationallicence Habitat degradation nationallicence Diet nationallicence Biodiversity nationallicence Eel conservation nationallicence Itakura Hikaru Atmosphere and Ocean Research Institute, University of Tokyo, 5-1-5 Kashiwanoha, 277-8564, Kashiwa, Chiba, Japan aut Kaino Tsubasa Atmosphere and Ocean Research Institute, University of Tokyo, 5-1-5 Kashiwanoha, 277-8564, Kashiwa, Chiba, Japan aut Miyake Yoichi Atmosphere and Ocean Research Institute, University of Tokyo, 5-1-5 Kashiwanoha, 277-8564, Kashiwa, Chiba, Japan aut Kitagawa Takashi Atmosphere and Ocean Research Institute, University of Tokyo, 5-1-5 Kashiwanoha, 277-8564, Kashiwa, Chiba, Japan aut Kimura Shingo Atmosphere and Ocean Research Institute, University of Tokyo, 5-1-5 Kashiwanoha, 277-8564, Kashiwa, Chiba, Japan aut Environmental Biology of Fishes Springer Netherlands 98/8(2015-08-01), 1871-1888 0378-1909 98:8<1871 2015 98 10641 https://doi.org/10.1007/s10641-015-0404-6 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10641-015-0404-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Itakura Hikaru Atmosphere and Ocean Research Institute, University of Tokyo, 5-1-5 Kashiwanoha, 277-8564, Kashiwa, Chiba, Japan aut NATIONALLICENCE 700 1- Kaino Tsubasa Atmosphere and Ocean Research Institute, University of Tokyo, 5-1-5 Kashiwanoha, 277-8564, Kashiwa, Chiba, Japan aut NATIONALLICENCE 700 1- Miyake Yoichi Atmosphere and Ocean Research Institute, University of Tokyo, 5-1-5 Kashiwanoha, 277-8564, Kashiwa, Chiba, Japan aut NATIONALLICENCE 700 1- Kitagawa Takashi Atmosphere and Ocean Research Institute, University of Tokyo, 5-1-5 Kashiwanoha, 277-8564, Kashiwa, Chiba, Japan aut NATIONALLICENCE 700 1- Kimura Shingo Atmosphere and Ocean Research Institute, University of Tokyo, 5-1-5 Kashiwanoha, 277-8564, Kashiwa, Chiba, Japan aut NATIONALLICENCE 773 0- Environmental Biology of Fishes Springer Netherlands 98/8(2015-08-01), 1871-1888 0378-1909 98:8<1871 2015 98 10641