INVESTIGADORES
MILANO daniela
artículos
Título:
Response of rainbow trout to different food web structures in Northern Patagonia: Implications for growth, bioenergetics and invasiveness
Autor/es:
JUNCOS, ROMINA; MILANO, DANIELA; MACCHI , PATRICIO J.; ALONSO, MARCELO F.; VIGLIANO,PABLO H
Revista:
TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY
Editorial:
AMER FISHERIES SOC
Referencias:
Lugar: London; Año: 2011 vol. 140 p. 415 - 428
ISSN:
0002-8487
Resumen:
Rainbow
trout Oncorhynchus mykiss have successfully colonized almost all available
water bodies in Patagonia. Introduction and restocking practices have taken
place since the beginning of the 20th century without prior consideration of
differences between environments in terms of fish community composition and
trophic food web structure. We assessed how observed growth, growth efficiency,
production, and biomass of rainbow trout populations from four Patagonian lakes
were influenced by food web structure and prey quality, and we evaluated the growth
strategies adopted by this species in response to environmental differences.
Fish communities vary in terms of species composition and dominance.
Bioenergetics simulations showed that size and growth patterns of rainbow trout
varied between lakes, mainly owing to dietary differences. Fewer and
lower-quality food items led to low growth efficiency and stunted growth, while
a more diverse and higher-energy diet base led to higher growth efficiency and larger
sizes. Rainbow trout density, production, and biomass were higher in the
larger, more structurally complex lakes, although rainbow trout production
values in the smallest lake were comparable with those in a lake twice its size.
This study provides comparative evidence of the high plasticity of rainbow
trout, for which the adoption of different growth strategies facilitates the
successful colonization of environments where diet bases range widely in quality.