Fisheries time series
Move to → Fishing geography, commercial concentrations of fish species and their migration routes in 1977-2010
The ichthyofauna of the Barents Sea is composed of more than 180 fish species and subspecies (Karamushko, 2008). The main commercial fish species are bottom species such as cod, haddock, and pelagic species such as capelin and Polar/Arctic cod.
A database has been developed and formed at MMBI KSC RAS (Matishov, Zhichkin, 2008) ). Charts of monthly catches of cod, haddock, capelin, and Arctic/Polar cod by the Russian vessels in the Barents Sea for the period of 1977-2010 have been constructed.
The data of daily records of fishing vessels of various types were used as the primary and initial material for mapping; the number of the vessels in the Barents Sea ranged during the year from 40-50 to 70-80 per month, and in some years (especially in summer months) exceeded 100. Daily records and information from research vessels of the fishing survey (from 2 to 5 vessels every month during a year searching for commercial concentrations of bottom fish species) were also used. The database contains information on the fishing grid area, number and type of vessels, and volume of the catch/fish caught.
Distribution charts of fishing vessels provide a visual of the fishing geography, commercial concentrations of fish species and their migration routes (Figure 1).
During the years with cold hydrological conditions (1977-1982) cod migrated mostly in an eastern direction (Figure 1А). However, the commercial concentrations of cod during those years did not go outside the Murmansk shallow water areas and the western slope of the Severo-Kaninskaya/North Kanin fishing grounds/bank
The schoolings did not reach the coastal waters of the Novaya Zemlya nor the slopes of the Gusinaya fishing grounds/bank since their migrations are restrained by cold water. Fishing activities were thus concentrated in the southern and southwestern areas of the sea. At the same time, the migration of cod to the North was rather weak (Zhichkin, 2009).
As a warm phase in climatic fluctuations began in the early 1990s, the redistribution of the migration routes and flows of cod took place. The fishing area enlarged both in the eastern and northern directions (Matishov et al., 2010). In the East, the concentrations of cod in September-October reached the coastal waters of the Novaya Zemlya between 70-74°N.L., though the main migration flow directed north up to 79°N.L. (the area of Nadezhda, the Perseus Uplands) (Figure 1B).
Analysis of distribution charts of commercial concentrations of haddock for the last 25 years indicates that haddock, similar to cod, reacts to the change of heat state/content of water masses. During the warming periods haddock can be found anywhere in the Barents Sea. During the cooling periods, the geographical range of haddock is reduced. As a result of the Barents Sea warming during the last two decades, the geographical ranges of haddock are broadened to the east and north.
During the initial warm phase of climatic fluctuations in the 1990s, the concentrations of haddock were registered on the slopes of the Severo-Kaninskaya/North Kanin and Gusinaya fishing grounds. These are areas where haddock had limited distribution as noted in early catch records. During the first decade of the 21st century, the total volume of the haddock catch of the entire sea gradually increased and reached its maximum value in 2007-08. However, a local cooling event occurred in 1997-98, which briefly paused the commercial increases of haddock.
In 2001 an extension of fishing areas occurred in a northern direction toward the Spitsbergen Archipelago (Svalbard), which led to an increase in rationing of the catch. In 2008-09, the commercial fishery recovered due to an increase in heat content in sea waters in the areas of the Western and Northern Spitsbergen between 79 and 80°N.L. (Figure 2).
Analysis of capelin concentrations for the period of 1977-2010 indicates that fishing areas are not permanent and change from year to year depending on the heat content/thermal conditions of the Barents Sea. In cold years, the main part of capelin fishing was in the north-western and northern areas, whereas in warm years considerable amounts of fish were concentrated in the eastern areas of the sea. For example, during the abnormally cold period of 1980-1981 main concentrations of capelin were found in the areas of Nadezhda, Central Uplands, the Perseus Uplands, and Sudkap trough (Figure 3А).
During the warm period of 1992, the concentrations of capelin moved east, and the main fishing areas in September-December were the Novaya Zemlya fishing grounds/bank, the south-eastern part of the Perseus Uplands, and the area of the Admiral Teistvo Peninsula (Figure 3Б).
Negative anomalies of water temperature in the layer of 0-200 m are likely responsible for a shift in spawning areas of capelin to the west toward the coast of Norway. For example, the main spawning during the cold period of 1980-81 was near the Varanger Peninsula and in the area of /Sore/Sore and Fuley fishing grounds/banks. In contrast, the positive temperature anomalies of water masses contribute to higher migration concentrations of capelin to the coast of the Kola Peninsula. This was observed again during the warm years of the last decade (Matishov, Zhichkin, 2013).
The distribution of commercial concentrations of Polar/Arctic cod is closely linked with water temperature variability. The colder the Barents Sea water is in the autumn-winter months, the further west and south of the Novaya Zemlya coast Arctic/Polar cod migrates. For example, during the cold period of 1998 Arctic/Polar cod fishing was on the southern slope of the Gusinaya fishing grounds/bank and near Kolguev Island. During the warm period in 2007, fishing activities occurred in the coastal waters of the Novaya Zemlya (the area of the Admiralty/Admiralteistva Peninsula) and the area adjoining the Kara Strait/Kara Gates (Figure 4).
Fishing geography, commercial concentrations of fish species and their migration routes in 1977-2010
To view the map, select the section and push the corresponding icon:
|- Geography of haddock fishery;||- Geography of the fry;|
|- The geography of the cod fishery;||- Geography of the capelin fishery.|