Barents Sea: projects/activities

The present project includes one pilot study of wild adult glaucous gull (Larus hyperboreus) and one experimental study of glaucous gull chicks raised in captivity. The pilot study of adult gulls gave us enough blood and tissue samples to develop the methods needed for immune system analysis in the laboratory experiment. In the experimental study a total of 39 glaucous gull chicks were hatched and raised in captivity in Svalbard, Norway. The chicks were divided into two groups. One experimental group (20 chicks) was given food that mimicked the “natural” food found in the marine environment. The control group (19 chicks) was given “clean” food. After 56 days the chicks were sacrificed in order to collect samples for analyses of organochlorines (OCs) and immunocompetence measurements. The experimental group had 2.8, 3.9, 5.0, and 6.1 time’s higher concentrations of HCB, Oxychlordane, ?DDT, and ?PCB, respectively, compared to the control group at day 56. All chicks used in the experiment were immunised with various vaccines and sera in order to test their ability to respond against foreign antigens. The experimental chicks produced low levels of virus neutralising antibodies when tested against the herpes virus and reovirus. They produced higher levels of neutralising antibodies when tested to tetanus toxoid. There was, however, no difference between the experimental groups with regard to the mean antibody titres. The chicks in both groups also responded to the influenza virus by increasing the production of specific antibodies. However, the mean antibody titre in the exposed group was significantly lower than in the control group. The mitogen-induced response of blood lymphocytes to PHA and LPS was significantly higher in the exposed group compared to the control group. The specific response of blood lymphocytes to Con A, PWM, KLH, TET, and PPD was higher in the exposed group compared to the control group. However, do to high variance in the exposed group there was no significant difference between groups with regard to the lymphocyte response to these mitogens. The results from the present study indicate a toxic effect of OCs on the glaucous gull chicks, which induced a systematic activation of the immune system. Further work on data will be performed.

Due to the high organochlorine concentrations reported in Arctic top predators, and the potential transport of contaminants with the drifting sea-ice in the Arctic, organisms constituting lower trophic levels living in association with sea-ice have been proposed as susceptible of uptake of high loads of organic pollutants. The present project studies the organochlorine occurrence in organisms living in the marginal ice zone north of Svalbard and in the Fram Strait. This includes both ice fauna (ice-amphipods), zooplankton, polar cod and different seabird species foraging in the marginal ice zone. Our objectives are to investigate: *The bioaccumulation of organochlorines in ice-associated amphipods in relation to diet preference, spatial variation due to sea ice drift route, size, sampling year, uptake and distribution within the body. *Comparison of organochlorine contamination in pelagic and ice-associated organisms at the similar trophic position, to investigate the effect of sea ice as a transporter and concentrator of pollutants. *Spatial variation in zooplankton species, related to differences in water masses and exposure to first year or multi year sea ice. *The contamination load in different seabirds feeding in the marginal ice zone, in relation to diet choice and estimated trophic position, taxonomically closeness and the induction of hepatic CYP P450 enzymes.

In 1994, analyses of sediments and fish from Lake Ellasjøen on Bear Island revealed a surprising scenario. The analytical results indicated some of the highest values of the contaminants PCB and DDT in freshwater sediments and fish ever found in the Arctic. The 1994 results were based on limited amounts of samples. During 1996 and 1997 there were carried out new sampling and analyses of several samples. These results verify the results found in 1994. Since the POP-patterns found deviate considerably from the typical patterns expected for local contamination, no local source can be assumed to be responsible for the high POP values found. Thus, the questions that need to be addressed include the source of these contaminants, the transport pathways that deliver these contaminants to this site, total deposition and finally contaminant fate including biological uptake and effects. Previous investigations from the early 80’s on high volume air samples carried out at Bear Island revealed several long-range transport episodes from Eastern Europe. The overall objective of this project is to contribute significant new information to the understanding of contaminant pathways in the Arctic hydrosphere and to provide a better understanding of contaminant focusing in a sensitive polar environment. This will be accomplished through the development of a comprehensive mass balance study of the atmospheric loadings of PCBs and other contaminants to the Lake Ellasjøen watershed to determine the seasonal importance of atmospheric deposition on a remote polar island. Further, effort will be directed at assessing the relative importance of various source regions of contaminants to the island through an evaluation of contaminant signatures and back trajectories of pollution events.

The aim of the project is to detrmine the content of organic contaminants in sea ice (including dirty ice), sea water (particulate and dissolved), snow, ice algae and phytoplankton collected in the marginal ice zone of the Barents Sea and in Fram Strait, and to calculate bioconcentration factors from the abiotic compartments to the lowest trophic levels of the food chain. Silicate measurements were included in the Fram Strait as water mass tracer. The Barents Sea represents an area influence mainly by first year ice with sea ice formed in the area and or in the Kara Sea, and and strongly influenced by the inflowing two branches of water of Atlantic origin. Samples were collected on a transect along the ice edge and at two transects into the ice. The stations across the Fram Strait were taken in regions affected by water masses and sea ice from differents regions and age. In the western sector, the upper water column was influenced by the inflowing west Spitsbergen current of Atlantic origin and mainly with first-second year ice, while the easter station was influenced by outflowing water from the Arctic Ocean and multiyear sea ice of more eastern origin.

Previous studies (Akvaplan-niva 1994 and 1996) on levels of POPs in limnic systems on Bear Island have shown that sediment and fish from a lake on the southern part of the island (Ellasjøen) have some of the highest levels of PCB and DDT that has been reported from Arctic areas. In a lake situated in the more central part of the island (Øyangen) levels are much lower, and in the same range as reported for lakes in Northern Norway and the Canadian Arctic. No local sources for contamination exist on Bear Island, and it is therefore likely that the contaminants are brought to the island with long-range atmospheric transport. The difference between the two investigated lakes on Bear Island may be due to differences in deposition of precipitation. This theory is currently being investigated through another project called: “Ellasjøen, Bear Island - A mass balance study of a high contaminated Arctic area." Another possible sources for contaminants to Ellasjøen can be the large colonies of seabirds that are situated close to the lake or use the lake for bathing. These seabirds may accumulate contaminants through their marine food chains and deposit guano in Ellasjøen and surrounding areas. Øyangen is much less influenced by seabirds than Ellasjøen. The aim of the present project is to map levels of selected persistent organic pollutants and study their biomagnification in freshwater and marine food chains at/near Bear Island. By linking the results from freshwater and marine food chains we aim to elucidate whether trophodynamics and interaction between marine and terrestrial food chains can be a natural mechanisms for biomagnification of POPs in specific geographic areas.

To clarify whether metals and/or POPs affect marine fish species - Atlantic cod (Gadus morhua) and plaice (Pleuronectes platessa)