INSTITUTO DE LIMNOLOGIA "DR. RAUL A. RINGUELET"
Unidad Ejecutora - UE
"BIOLOGICAL TRAITS AND GROWTH PATTERNS OF PEJERREY ODONTESTHES ARGENTINENSIS"
LLOMPART, F.; COLAUTTI, D. C.; MAIZTEGUI, T.; CRUZ-GIMENEZ, M.; BAIGÚN, C. R. M.
JOURNAL OF FISH BIOLOGY
WILEY-BLACKWELL PUBLISHING, INC
Lugar: Londres; Año: 2013 vol. 82 p. 458 - 458
This study assesses for the first time the relationship between annual cycles of different Biological indices with growth patterns of a marine pejerrey Odontesthes argentinensis population near its southern-distribution boundary in north Patagonia. The reproductive period is between September and November evidenced by an increase of the gonado-somatic index with a peak in October corresponding to spawning. The reproductive cycle was also coupled with metabolism processes related to energy allocation as shown by changes in the hepatosomatic index and body condition. Total length (LT) at maturity was 270 and 282 mm for females and males whereas fecundity was estimated at mean ± S.D. = 9380 ± 1797 mature oocytes. Based on marginal increment analysis, most of the scales showed a maximum value during the summer, with a sharp decline thereafter during the autumn and winter, indicating that scale rings are formed during the latter period and only once a year. Growth fitted by the von Bertalanffy model for both males and females did not show significant differences and showed a rapid growth during the first 2 years. The shorter reproductive period compared with the northern O. argentinensis populations inhabiting tropical and subtropical areas was interpreted as an adjustment to temperate environmental conditions. The larger maximum LT and LT at first maturity are in agreement with the counter gradient hypothesis and could be related to the selective effects of low temperature and a shorter growing season. This latitude dependency argues strongly against the application of the same fishing regulations for different O. argentinensis populations as a whole and reinforces the need to assess basic biological features at a population scale to promote local sustainable fisheries management.