title: Possible food sources of macrozoobenthos in the manko mangrove ecosystem, okinawa (Japan): a stable isotope analysis approach.
abstract: Identifying potential food sources in mangrove ecosystems is complex because of the multifarious inputs from both land and sea. This study, which was conducted in the Manko mangrove ecosystem of Okinawa, Japan, determined the composition of the stable isotopes δ(13)C and δ(15)N in primary producers and macrozoobenthos to estimate the potential food sources assimilated and to elucidate the target trophic levels of the macrozoobenthos. We measured the two stable isotope signatures of three gastropods (Cerithidea sp., Cassidula mustelina, Peronia verruculata), two crabs (Grapsidae sp., Uca sp.), mangrove tree (Kandelia candel) leaves, and sediment from the mangrove ecosystem. The respective carbon and nitrogen isotope signature results were as follows: -22.4‰ and 8.6‰ for Cerithidea sp., -25.06‰ and 8‰ for C. mustelina, -22.58‰ and 8‰ for P. verruculata, -24.3‰ and 10.6‰ for unidentified Grapsidae, -21.87 ‰ and 11.5 ‰ for Uca sp., -29.81‰ and 11‰ for K. candel, and -24.23‰ and 7.2‰ for the sediment. The stable isotope assimilation signatures of the macrozoobenthos indicated sediment as their food source. Considering the trophic levels, the stable isotope values may also indicate that the five macrozoobenthos species were secondary or higher consumers.
authors.affiliation: Department of Aquatic Resources Management, Faculty of Fisheries and Marine Science, Bogor Agricultural University, Bogor 16680, Indonesia.
authors.forename: Yusli
authors.initials: Y
authors.lastname: Wardiatno
authors.affiliation: Department of Biology, Faculty of Science and Technology, State Islamic University Syarif Hidayatullah Jakarta, Tangerang Selatan 15412, Indonesia.
authors.lastname: Mardiansyah
authors.affiliation: Department of Marine Science and Technology, Faculty of Fisheries and Marine Science, Bogor Agricultural University, Bogor 16680, Indonesia.
authors.forename: Tri
authors.initials: T
authors.lastname: Prartono
authors.affiliation: Faculty of Science, University of the Ryukyus, Nishihara, Okinawa 903-0213, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Tsuchiya
keywords: Food Source; Macrozoobenthos; Mangrove Ecosystem; Stable Isotope; Trophic Level