| 要旨トップ | 目次 | 日本生態学会第69回全国大会 (2022年3月、福岡) 講演要旨
ESJ69 Abstract


一般講演(口頭発表) B03-02  (Oral presentation)

Measuring individual specialization in diet of a generalist marine snake using multi-tissue stable isotope analysis【EPA】

*Kanta FUJISHIMA, Ayano MEDO, Hideaki NISHIZAWA(Kyoto Univ.)

The quantification of intra-population niche variation including individual specialization can provide valuable implications for population dynamics and behavioral adaptations. Laticauda semifasciata is a marine snake which preys on various fish taxa in a wide range of depths and substrate types. We investigated intra-population trophic variation in this generalist species using stable isotope analysis of carbon and nitrogen. For analysis, ventral scales, red blood cells, and plasma were sampled from adult snakes (12 females and 19 males) at Ishigaki Island. The overall isotopic values of L. semifasciata were characterized by a wide range in δ13C and relatively limited range in δ15N. Females were larger in body size and had significantly lower δ13C values than males. Multi-tissue stable isotope analysis revealed extreme individual specialization in δ13C, and to a lesser extent, in δ15N as well. The relatively depleted 13C in females may reflect a higher reliance on deeper, pelagic foraging grounds, facilitated by increased diving capacities due to having a larger body. Our results of individual specialization suggest that despite exploiting a wide range of habitats at the population level, individual L. semifasciata likely use limited habitat types or possibly locations to feed, where they adopt habitat-specific foraging tactics.


日本生態学会