The diet of the large puyén Galaxias platei (Galaxiidae)

CASAUX R.J.; DI PRINZIO C.Y.

aqua, International Journal of Ichthyology

Año: 2007 vol. 13 p. 77 - 86

In total, 1,355 large puyén (Galaxias platei) specimenswere caught using trammel-nets laid on the bottom ofRosario Lake, Argentina. This fish was the most numerousspecies in the catches, followed by the Patagonian silverside(Odontesthes hatchery) and the rainbow trout (Oncorhynchusmykiss). The analysis of 333 stomach contents indicatedthat G. platei is a generalist and opportunistic feeder,preying mainly on benthic organisms. The amphipodHyalella araucana was the main prey, followed by the chironomidsAblabesmyia sp. and Polypodilum sp. Hyalellaaraucana predominated in the diet of fish of all sizes andwas almost the only prey item in larger individuals,whereas chironomids were important alimentary items insmaller specimens. Galaxias platei preyed intensively on H.araucana throughout the year but seemed to take advantageof alternative prey species, such as chironomids, whenthey were available and abundant. The results are comparedwith previous studies carried out in Patagonia.