Stretching across the Pacific between 45°N and the coast of Alaska (Fig. 1) is an oceanic region referred to as subarctic. It is part of a broader oceanic region in which major phytoplankton nutrients (nitrate, phosphate, and silicate) apparently are never depleted from the surface layer. Persistently high nutrient concentrations are found along the entire eastern edge of the Pacific with westward extensions in the subarctic and along the equator and with eastward extensions through Drake Passage and then around the globe south of 35°S (Reid, 1962). Ecological relationships vary dramatically along this nutrient-replete belt, and assembly of a complete comparative ecology for all of its distinctive parts has only begun.