Födoval hos juvenil piggvar (Psetta Maxima) : effekter av bytesstorlek

• Main Author: Nygren, Daniel
• Format: Bachelor Thesis
• Language: Swedish
• Published: Högskolan på Gotland, Avdelningen för Biologi 2009
• Subjects: Biology; Biologi; Turbot
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:se:hgo:diva-281

The effects of prey size on prey choice in different cohorts of juvenile turbot (Psetta maxima)were studied in three nursery areas at Gotland. Prey length measurements showed that gobies(Gobiidae) increased in average length during the season, while mysids (Mysidae) did not.Experiments on predation capacity of different size classes of turbot on different size classesof prey showed that juvenile turbot easily can eat gobies that are up to two thirds of their ownbody length, while the body size of turbot does not have any effect on the predation capacityon mysids. Stomach content of 217 turbots, less or equal 35 mm, was analysed to see if therewas any change in diet during the season, but there was no significant change in diet. Theoverall conclusion was that early settlers most likely have an advantage due to greater accessof alternative prey.