Feeding habits of huchen Hucho hucho (Salmonidae) fry in the River Tresnjica, Yugoslavia

Abstract

About 10 000 huchen larvae, obtained by artificial spawning, were introduced on 28 May 1995 into the River Tresnjica, a tributary to the River Drina, using procedures applied routinely by local fishing associations. During next two months, only 33 fry were caught in the river. Nevertheless, valuable information has been obtained for the first time on young huchens in the Drina basin. The fry apparently selected slower or almost stagnant water habitats outside the main river course. The variability of prey organisms found in fry stomachs decreased with fry length. Larger and particularly motile prey, especially mayfly larvae, gradually dominated the fry diet. Also for the first time, we document homing instinct in huchons with mark-recapture information: one out of the nine adults, tagged after spawning, was recaptured the following year at the same spawning site.