The Okhotsk Sea is one of the most biologically productive regions in the world with high fisheries production. Several previous reports indicate that primary productivity in the Okhotsk Sea is very high especially on the continental shelf. The Okhotsk Sea is well known as one of the southernmost zones of seasonal sea ice in the Northern Hemisphere. The most important factor required to characterize spatial and temporal variability of spring blooms was the timing of sea ice retreat, while a secondary factor was the adjustment of insolation. The beginning of the spring bloom in the Okhotsk Sea depends on the adjustment of the light environment, and that the presence of sea ice controls light intensity in the surface water and thereby controls the timing of the spring bloom. There is little information on iron concentration in the Okhotsk Sea but Fe(III) solubility in the surface mixed layer is generally high and variable (0.3-0.7nM) in the southern Okhotsk Sea. The concentration of inorganic nitrogen varied in the upper mixed layer from 1-3 µM in the center of Okhotsk Sea in summer. Nitrate can be depleted after the spring phytoplankton bloom in the western region of the Okhotsk Sea. These facts suggest that iron supply is higher in the Okhotsk Sea than in the western subarctic Pacific and that phytoplankton growth is not limited by iron availability in the Okhotsk Sea. The main source of iron in the Okhotsk Sea is not known. At least along the coast of Hokkaido, the Okhotsk Sea is a well known for its scallops, Hanasaki crab, chum salmon and herring resources. An important consideration in the region is that the food for benthic animals is mainly supplied by the ice algae and the spring bloom after the ice floes are removed.

	to develop the Okhotsk Sea component of PICES Future Program
	to identify key scientific questions
	to identify gaps of knowledge and necessary approaches
	to exchange and share most recent and basic knowledge on the sea