The Most Abundant Grenadiers of the Russian Far East EEZ: Distribution and Basic Biological Patterns
Vladimir N. Tuponogov, Alexei M. Orlov, Leonid S. Kodolov
Abstract.—Giant grenadier Albatrossia pectoralis, popeye grenadier Coryphaenoides cinereus and Pacific grenadier C. acrolepis are commercially important in the Russian Far East and dominate on continental slopes at depths above 400–600 m. Giant grenadier have become the target of a Russian bottom trawl fishery during recent years. Juveniles of grenadiers inhabit midwater layers until maturation. Commercial aggregations of adults occur near and over the bottom at depths from 300–600 m to 1,500–2,000 m. There are no considerable inter-annual changes in patterns of spatial distribution. Seasonal migrations of grenadiers are poorly understood. It was believed that they do not perform lengthy migrations, but giant grenadier has been shown to migrate along the Kuril Islands. This species is the most abundant grenadier in the study area. Ripe individuals occur all year but main spawning happens during summer and autumn. Diets of the three grenadiers differ significantly. Giant grenadier consumes benthic and interzonal organisms, Pacific grenadier eats mostly benthic invertebrates, while popeye grenadier prefers pelagic prey. Difficulties faced by the fishery include the depth of fish and poor flesh quality, which means stocks have not been heavily exploited. Processing of grenadiers for human consumption, including flesh, canned eggs, and liver, could make their harvesting more profitable.