Behavioural responses of larval and juvenile walleye pollock (Theragra chalcogramma): possible mechanisms controlling distribution and recruitment

Pertinent examples of the behavioural capabilities of walleye pollock ( Theragra chalcogramma (Pallas)) eggs, yolk-sac larvae (free embryos), feeding larvae, and juveniles to respond to environmental factors, both biotic and abiotic, are presented. The selection of these factors is based on the differing habitats that each life stage occupies and the ontogenetic changes in ecological requirements as fish recruit from one life stage to the next. Also considered are the ways in which intrinsic factors may modify the behavioural responses of particular life stages to environmental factors. Results of experiments illustrate the manner in which behavioural studies conducted under controlled laboratory conditions may be used to further understanding of mechanisms controlling distribution, recruitment, and survival of marine fish. Also shown is the way that experimental conditions appropriate to particular life stages allow fish to express their behavioural potential and ensure that laboratory findings have ecological relevance. Findings are compared with those for other species residing in similar and different habitats.

Article from Marine Science Symposia Vol. 201 - "Mass rearing of juvenile fish". Symposium held in Bergen, 21-23 June 1993. To access the remaining articles please click on the keyword "MSS Vol. 201".