Abstract
Distribution records and ecological studies of mangrove animals were investigated in the tidal flat and mangrove. However, few studies have assessed the influence of these animals on the surrounding environment. For clarifying the effect of mangrove animals on material balance, we examined the resource amount of the mudskipper Periophthalmus argentilineatus and its amount of assimilation of C,N,P. The mudskipper, P. argentilineatus inhabits the intertidal zone and is active on tidal flat surfaces during low tides. Between 2004 and 2007, we found that the population level of this species collected at the Udara River Estuary, Iriomote Island, increased each year. Juvenile fish represented 78－87% of the total captured fish. It is suggested that our investigation conspired at juvenile fish's land life shift time. Efficiency of the amount food of mudskipper were approximately 2.3－6.5%, which was noticeably lower than that of the other fish species. Fish's assimilation of C,N,P in 3 years that study area is 33~833gC, 8~215gN, 2~43gP, we suspected that this was related to the population growth. The C,N,P assimilation by P.argentilineatus were comparatively low, suggesting high energy expenditure by this species because it lives in a tropical area.
