The relationship between Calanus plumchrus and hydrographic parameters has been investigated. The copepod is associated with Strait of Georgia bottom water from July to January. This association is not found in the early developmental stages, which are present from February to July and are most commonly in near surface waters. The onset of maturation and breeding precedes the spring phytoplankton bloom; some environmental parameters appear to function as cues to this timing. The nature of these cues is not clear; no single parameter would seem to be capable of producing the observed effect. C. plumchrus overwinters in a state of arrested development similar to diapause. / Science, Faculty of / Zoology, Department of / Graduate