Premium
Low efficiency of dietary carbon and nitrogen conversion to growth in an herbivorous coral‐reef fish in the wild
Author(s) -
Polunin N. V. C.,
Brothers E. B.
Publication year - 1989
Publication title -
journal of fish biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.672
H-Index - 115
eISSN - 1095-8649
pISSN - 0022-1112
DOI - 10.1111/j.1095-8649.1989.tb03038.x
Subject(s) - damselfish , biology , coral reef fish , reef , coral reef , herbivore , coral , fishery , zoology , ingestion , otolith , fish <actinopterygii> , ecology , biochemistry
Annual ingestion and body growth have been estimated for average‐sized adult (mean s.l. 62.7 mm) jewel damselfish. Plectroglyphidodon lacrymatus (Quoy et Gaimard), on a shallow fringing reef of southern Papua New Guinea. Mean ingestion (calculated from daily algal‐food consumption in winter, the relationship between water temperature and feeding activity, and C, N and P contents of algal food) was 304.3gC year, 20.4gN year −1 and 3.5gP year −1 for this herbivorous fish. Mean body‐growth rates for the fish were 5.7 mm year −1 , from SEM analysis of sagittal‐otolith microstructure, and 6.2 mm year −1 from a mark‐release‐recapture study in the wild. Based on C and N analyses of whole fish and the dry‐weight/s.L. relationship, the gross growth efficiency of these fish was 0.2% for C and 0.5% for N. These very low efficiencies indicate that although P. lacrymatus ingests and absorbs a high proportion of algal production in its territory, only a small part of the assimilation goes into body growth and is thus potentially available to piscivorous fish higher in the food‐chain.