one publication added to basket [67438] | Ontogenetic and temporal fluctuations in feeding habits of the Chilean croaker Cilus gilberti (Perciformes, Sciaenidae) in southern Chile
Oyarzún, C.; Fernández, C.; Landaeta, M.; Cortés, N. (2001). Ontogenetic and temporal fluctuations in feeding habits of the Chilean croaker Cilus gilberti (Perciformes, Sciaenidae) in southern Chile. Cah. Biol. Mar. 42(3): 295-302
In: Cahiers de Biologie Marine. Station Biologique de Roscoff: Paris. ISSN 0007-9723; e-ISSN 2262-3094, more
| |
Authors | | Top |
- Oyarzún, C.
- Fernández, C.
- Landaeta, M.
- Cortés, N.
|
|
|
Abstract |
The natural diet of Cilus gilberti was investigated from samples collected between December 1997 and November 1998 in Southern Chile. This study showed the possible influence that seasonal changes and ontogenetic development of individuals may have on their feeding habits. The information was obtained by stomach contents analysis of 764 specimens caught by small scale fishery and comprising the whole legal capture size spectrum. Twenty six prey items (grouped in five major taxa) were found. Five month groups (Trophic Seasons, TS) were also identified. According to the quantitative analysis, C. Gilberti behaves as an eurphagic, carnivorous species, feeding mainly on small fish (Engraulis ringens and Strangomera bentincki). During certain periods of the year, environmental changes can provoke a shift in prey importance toward small crustaceans (Neotrypaea uncinata) which increase dramatically in abundance during winter. The structure of the population adapts to changes in the environmental offer, and maintains the ontogenetic organization, which includes a Ontogenetic Trophic Unit of middle sized fish (61-75 cm TL), that remains constant during most of the year, except during summer (december-january) and winter (june-july) periods. |
|