The effects of illuminance and substrate location on the settlement of glaucothoe of the red king crab Paralithodes camtschaticus (Tilesius, 1815) (Decapoda: Lithodidae)

The effects of illuminance and the location of substrate relative to the water and bottom surfaces on the settlement process in red king crab glaucothoe was studied for the first time. Studies were conducted in the laboratory under natural illumination conditions; propylene fibers were used as a substrate. During the first half of the stage, glaucothoe swam in the water column mostly in the daytime. No daily dynamics in the distribution of glaucothoe were observed. Glaucothoe preferred well-lit substrates near the water surface. When individuals metamorphosed to the first juvenile stage, they migrated from the substrates to the bottom of the tank.