ONTOGENIC CHANGE IN EFFECT OF LIGHT INTENSITY AND TURBIDITY ON PREY CAPTURE BY LARVAL STRIPED BASS


C.E. White, J. Duston

Abstract:

The capture of Artemia salina by larval Morone saxatilis was quantified under four treatments (each replicated) in a 2*2 factorial design: 2 lux and 0 nephelometric turbidity units (NTU), 2 lux and 50 NTU, 20 lux and 0 NTU, and 20 lux and 50 NTU. Eight black plastic tanks illuminated by incandescent bulb/neutral density filters were each filled with 30L brackish water made turbid by adding clay. Gentle aeration kept both clay and prey in suspension. Fish were acclimated to tanks for 2-6h, then Artemia were added to a density of 0.1/ml. After 60 minutes, prey capture rates were determined by one of two methods depending on larval age: a) counting number of prey in gut (<15 days post hatch, dph); b) estimating decrease in prey density in tank (15 dph

(Dept. Plant & Animal Sciences, Nova Scotia Agricultural College, Truro, NS B2N 5E3, Canada)


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