Summary and conclusions

Introduction

Tue, 12 Jan 2010 14:20:39 +0000

This report was initiated by the Joint Russian - Norwegian Commission on Environmental Cooperation and the work herein has been carried out in co-operation with the Joint Russian-Norwegian Fisheries Commission. The main objective is to provide a comprehensive description of the Barents Sea ecosystem using relevant scientific knowledge from both Russian and Norwegian scientist. The work has been based on the positive experiences with previous Barents Sea ecosystem status reports prepared jointly by PINRO in Russia and Institute of Marine Research in Norway. The report will contribute to the scientific basis for development of an ecosystem-based management plan for the Russian part of the Barents Sea and contribute to the further development of ecosystem-based management in the Norwegian Territories within the area, via the Norwegian Barents Sea Management Plan.

General description of the Barents Sea ecosystem

Tue, 12 Jan 2010 14:21:39 +0000

The Barents Sea is a sub-Arctic shelf ecosystem located between 70° and 80°N. It connects with the Norwegian Sea to the west and the Arctic Ocean to the north. The dynamics of the system are strongly influenced by the inflow of warm Atlantic water from the west. This water mass is separated from Arctic Water by the ocean Polar Front, which is characterised by strong horizontal gradients in temperature, salinity and concomitant differences in biodiversity supported within the various regions. The system is also dominated by seasonally occurring sea ice, particularly in the eastern and northern parts. A distinct assemblage of species is associated with sea ice.

Current status of the ecosystem

Tue, 12 Jan 2010 14:22:46 +0000

Important aspects of the status of ecosystem components and human activities as revealed by the most recent data are:

Temperatures were generally higher than average throughout 2008, but lower than the two previous years. Average sea-ice extent has declined during the last three decades and was below average in 2008 but higher than in 2007

Aspects of future change

Tue, 12 Jan 2010 14:25:16 +0000

The following aspects of possible long-term changes in the ecosystem are discussed in the report:

Although models generally project that the climate in the Barents Sea will get warmer, considerable differences exist between climate models. Predicting the magnitude and nature of the warming that is likely to occur is therefore associated with considerable uncertainty. It is highly likely, however, that any significant warming will cause shifts in species ranges. This means that more temperate species will become established in the area and that species already present, such as capelin and Northeast Arctic cod will tend to shift toward the north and east within the Barents Sea. In addition, sea ice extent will be reduced, and this will have a negative impact on ice-dependent flora and fauna, such as polar bears. Reduction in sea ice extent may also lead to increased primary productivity, if nutrient supply is not reduced significantly due to increased stratification in the water column. An increase in primary productivity coupled with other positive effects of increased temperature on fish growth and reproduction, may cause productivity of cod, haddock and other commercially important species to increase. However, negative effects on prey species may also occur. Thus, overall effects on fish productivity are hard to predict. Similarly, the many complex ways in which species interact creates considerable uncertainty in any set of predictions as to what the overall response of climate warming to the ecosystem will be

Issues relevant for ecosystem management

Tue, 12 Jan 2010 14:26:56 +0000

The following themes are highlighted as examples of issues that are relevant for development of ecosystem-based management:

Ocean acidification
Mixed fisheries, undersized fish, discard of catches, bycatches and IUU fishing
Impact of bottom trawling on benthos
Risk of accidental discharges from oil and gas activities and ship transport
Risk of introduction of alien species from ship traffic
Long range transboundary pollution that is transported by air and water currents
Risk of radioactive pollution

Future needs for monitoring and integrated status reports

Tue, 12 Jan 2010 14:29:12 +0000

The expected increases in the number and type of impacts on the ecosystem put a premium on more extensive monitoring in the future. New monitoring methodology and technology should be developed and implemented to fill the spatial and temporal gaps in current knowledge and on-going monitoring efforts. However, many ecosystem components will still depend on traditional surveys for necessary data collection for many years. During such surveys there is a strong need to capture information simultaneously from as many ecosystem components as possible to enable integrated and cost effective sampling.