Food availability in spring affects smolting in brown trout (Salmo trutta).

Prior to out-migration, salmonid fish typically undergo physiological and morphological changes - a process known as smolting. This study indicates that smolting in brown trout (Salmo trutta) is affected by feeding conditions in spring immediately prior to out-migration. This conclusion was reached after experimentally testing the effect of seasonal variation in food availability on smolt status in the spring. A migratory strain of trout was administered either high (H) or low (L) food rations in the autumn, winter or spring prior to release in the spring. Whilst fish growth or condition could be affected in any season, it was spring rationing that reduced growth and growth-related variables and which caused increased smolting. Our result supports the idea that smoltification and the decision to migrate is affected by spring food availability regardless of conditions in the previous autumn or winter.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author