SIZE STRUCTURE AND GROWTH RATE OF EUPHAUSLA PACIFICA OFF THE OREGON COAST

摘要

Fuphausia pacifica (Hansen) has a maximum life expectancy of about one year. During this time it grows rapidly to a length of 20-24 mm. Fur cilia larvae were found throughout the year but were most abundant during the autumn months. The population density and the proportion of juveniles was higher within 25 miles of the coast than in offshore oceanic watersnGrowth rates off Oregon are about twice those previously reported forvthis species from other regions. Spawning also appears to be later in the year. All these features may be explained by the high primary production which is extended throughout the summer by coastal upwelling and by the lack of wide seasonal fluctuations of water temperatures along the Oregon coast.