Typically only one generation per year, but up to three in some regions. Lifecycle consists of six naupliar stages, followed by five copepodid larval stages before final molt into adult. All stages exhibit daily vertical migration, but this is most pronounced in later stages. Population rises to near surface waters
0-98 ft (0-30 m), commencing just before sunset, feeds at surface during night, then begins to either sink or swim downwards by dawn, returning to daytime depths 98-1,640 ft (30-500 m). Can overwinter in a resting (diapause) phase at fourth or fifth copepodid stage, descending to 1,640 ft (500 m) and spending winter there, sustained by stored lipids.
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