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Giant grenadiers Albatrossia pectoralis inhabit the continental slope to depths in excess of 2,000 m from Baja California, Mexico, around the arc of the North Pacific Ocean to Japan, including the Bering Sea and the Sea of Okhotsk (Mecklenburg et al. 2002). The giant grenadier is by far the most abundant fish species in terms of biomass at depths of 200–1,000 m on the continental slope of Alaska (Clausen 2008). There has never been a directed fishery for giant grenadiers in the Gulf of Alaska (GOA), but they are frequently taken as bycatch in the sablefish Anoplopoma fimbria longline fishery. Currently, there are no catch limits or reporting requirements for giant grenadiers. Because they are relatively large (>14 kg), numerous, and widespread, they have economic potential, like other grenadiers that have been commercially exploited, such as roughhead grenadier Macrourus berglax (Fossen et al. 2003), roundnose Coryphaenoides rupestris (Atkinson 1995), and Pacific Coryphaenoides acrolepis (Clausen 2008).
Because of their abundance, giant grenadiers are likely to be an important component of the continental slope ecosystem in the North Pacific Ocean. The general characteristics of grenadier species (late maturity, slow growth, and high mortality after being discarded by a fishery) make giant grenadiers susceptible to overexploitation, although their biomass is currently stable (Clausen 2008). Many deep‐sea fishes that share these life history traits have been declared endangered according to World Conservation Union criteria, and eight other deep‐sea fishes have exhibited significant population declines (Devine et al. 2006; Baker et al. 2009). Of the eight that are endangered, two are grenadier species (roundnose and roughhead).
A study of giant grenadier age and growth off the U.S. West Coast, GOA, and Aleutian Islands found that age ranged from 13 to 56 years based on radiometric aging and otolith readings (Burton 1999). However, there was not good agreement between the results of the radiometric and otolith aging methods. More recently, giant grenadier catch and distribution have been described off Alaska (Clausen 2008), Kamchatka, and the northern Kuril Islands (Orlov and Tokranov 2008). Tuponogov et al. (2008) described the distribution of giant grenadiers from the Sea of Okhotsk, western Bering...