INIBIOMA   20415
INSTITUTO DE INVESTIGACIONES EN BIODIVERSIDAD Y MEDIOAMBIENTE
Unidad Ejecutora - UE
artículos
Título:
Intraspecific variation in growth and morphology of landlocked Galaxias maculatus during the limnetic period of its life history
Autor/es:
BARRIGA, J. P. ;; M. A. BATTINI; M. I. GARCÍA-ASOREY; C. CARREA; MACCHI, P.J; V. E. CUSSAC
Revista:
HYDROBIOLOGIA
Editorial:
SPRINGER
Referencias:
Año: 2012 vol. 679 p. 27 - 41
ISSN:
0018-8158
Resumen:
Food availability and predation risk have been shown to affect phenotypes during early life history of fishes. Galaxias maculatus, a small fish widely distributed around the southern hemisphere, clearly exhibits a complex trade-off between feeding and predation avoidance during growth over the larval period. We studied the effect of different environmental variables on diet, growth, mortality, and morphology through field surveys and data revision in the literature for limnetic G. maculatus larvae in five oligotrophic lakes of Patagonia. Both number of food categories and prey ingested by larvae were directly related to zooplankton density. Larval growth rate was related with zooplankton density and temperature. Lakes with high zooplank- ton densities and low predation risk had larvae with deeper bodies and shorter caudal peduncles, while in lakes with less food and high predation risk larvae were slender with shallower bodies and longer peduncles. Food availability and predation risk seem to operate on the swimming performance of G. maculatus larvae through the slenderness of the body and the length of the caudal peduncle. The observed phenotypic variation in growth and mor- phology could be a key feature that has allowed this species to successfully colonize a wide variety of environments in the Southern hemisphere.