Ontogeny of phototactic behavior in red drum larvae (Sciaenidae: Sciaenops ocellatus)

Abstract

Results indicate an ontogenetic increase in photo-responsiveness, beginning as early as Day 3 posthatch. Light-adapted larvae as young as Day 4 exhibited a lower response than dark-adapted larvae at the same stimulus intensities, indicating dark and light adaptation. There is sufficient daylight available throughout the water column in the field for photoperception by red drum larvae. Natural intensities at depth are adequate for visual predation during daylight hours. -from Authors