The Status of the Stock and the Current Fishery for the Atka Mackerel, Pleurogrammus monopterygius (Pallas, 1810), in the Olyutorsky–Navarin Area, Bering Sea

Abstract

The dynamics of the Atka mackerel stock in the Olyutorsky–Navarin area in 1994–2019 is inferred from bottom-trawl surveys, fishery statistics, open-access NOAA data, and the results of simulation by the method of virtual population analysis. After the period of low stock in the mid-1990s, the abundance of the Atka mackerel group in the area increased sharply to a maximum in 2006–2008, when the spawning biomass was estimated at approximately 9500 t and the fishery biomass at 14 000 t. In 2008, the stock showed a tendency to decrease; by 2013, the spawning stock decreased to 3600 t and the fishery stock to 5600 t; subsequently, there was a period of stabilization at a low level with a slight tendency to further reduction. One of the possible causes of the sharp increase in the Atka mackerel stock in the 2000s could be the increased transport of juveniles of strong year-classes from the main spawning grounds off the Aleutian Islands with their subsequent settlement on available parts of the shelf off Cape Olyutorsky. The development of the Atka mackerel fishery in the Olyutorsky–Navarin area in 1994–2019 had a pattern similar in general to the stock dynamics. Until 1995, no more than an average of 100 t were caught per year; in 2006–2010, the average annual catch increased to 790 t; in 2011–2015, it increased to 1150 t; and in 2016–2019, the catch again decreased to 950 t. Due to the emerging trend of a general reduction in the stock of the Aleutian population, this low level of catches in the Olyutorsky–Navarin area is expected to continue in the coming years.