Morphology of larval, postlarval, and early juvenile stages of the red king crab is described and illustrated from laboratory reared material; attention is directed to certain aspects of morphology not previously considered. Some behavioural patterns are clarified, with special emphasis on locomotion and feeding. Morphological criteria for distinguishing the first two juvenile stages are proposed; additional morphological criteria for distinguishing zoeal stages are reported. Data on development and growth rates under laboratory conditions at 7–8°C are given for early life history stages. No major morphological differences were observed between early life stages of the red king crab from the native area in the Pacific Ocean and from the Barents Sea.
Daily food intakes, optimal feeding regimes and food concentrations for laboratory reared Paralithodes camtschaticus (Tilesius, 1815) larvae were investigated. Artemia nauplii hatched at standard conditions were used as food. Daily food intakes of zoeae I-IV at 7-8°C comprised 11.3, 22.4, 33.2, and 41.8 nauplii individuals (ind) )1 day )1 , respectively, taking into account that wet weight of Artemia nauplii used for the experiments constituted 0.026 mg, dry weight 0.0042 mg. Optimal initial Artemia nauplii concentrations for feeding zoeae I-IV was determined as 400-600, 600-800, 800-1000 and 1000-1200 nauplii L )1 respectively. Recommendations on using Artemia nauplii as food for red king crab larvae were outlined on the basis of experimental results. Growth, development and survival rates of zoeae I-IV reared in recycling water system at 7-8°C and fed Artemia nauplii according to these recommendations were described.
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Phototactic responses of light-adapted zoeae IV, glaucothoe, and first stage juveniles of the red king crab to three intensities of white light were quantitatively measured under laboratory conditions. All stages observed were photopositive to all light intensities tested, except for late glaucothoe (10 days since moulting) which did not respond to light stimuli. Phototactic response changed in the early life history of the red king crab. The extent of photopositive movement decreased after each metamorphosis. Peak phototactic response in zoea IV were observed at a light intensity of 1.9 Â 10 13 q cm À2 s À1 , in early glaucothoe at 1.1 Â 10 10 q cm À2 s À1 and in juveniles at 1.3 Â 10 9 q cm À2 s À1 . The data on behavioural responses to light may provide a better understanding of the early life history, survival and recruitment of the red king crab and assist the development of feasible methods and techniques for aquaculture of this species.
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