The Use Of Gis-Technology For Estimation Of Thenortheast Arctic Cod Stock

No abstracts are to be cited without prior reference to the author.

The Northeast Arctic cod is one of the most important target species in the Barents Sea. The volumes of cod catches depend on the state of the fishable stock which is assessed by the ICES AFWG by the methods of analytical approach based on the theory of fisheries. Each day VNIRO receives the daily reports of vessels participating in the Russian fishery on cod, which contain the following information: date, coordinates, type of vessel, target object and its catch, type of trawl, duration of trawling. The authors set a task to estimate the fishable stock and TAC, basing on the Russian fishery data. In total, for the 2000-2006 the 181,068 reports were analyzed, from which the 89,028 ones were used to estimate the cod biomass. For each square (0.5o latitude x 2o longitude) it was determined by the 'area method' the 15-day periods. The cod biomass for the whole Barents Sea was computed as a sum of biomass estimates for the all squares which determined with the use of software package GIS ArcView, version 3.2 (by the company ESRI). The annual averages of biomass were determined as their arithmetical mean for the April-December period. In total, the 126 estimations of the cod fishable stock biomass in the Barents Sea were made. The results showed that in 2000-2006 the biomass ranged from 1.9 million tons to 2.8 million tons. In 2005-2006 fishable biomass are increased from 2.0 million tons to 2.6 million tons. The values of the fishable stock biomass obtained by our method were essentially higher that those by the ICES data. The proposed method allows to estimate the fishing biomass of cod in the on-line regime and to process the considerable volumes of information quickly.