Geir W Gabrielsen

Chlorinated hydrocarbons in glaucous gulls (Larus hyperboreus) in the southern part of Svalbard

Abstract In 1989, a number of glaucous gulls ( Larus hyperboreus ) were found dead near a seabird cliff at south Svalbard. In an effort to clucidate the course of death, 12 individuals were sent to the Central Veterinary Institute for autopsy and analysis of chlorinated pesticides and polychlorinated biphenyls (PCBs) in samples of liver, kidney, brain and muscle. Eggs of common and Bru¨nnichs guillemots constitute important food for glaucous gulls during the nestling period, thus 13 eggs (3 eggs from common and 10 eggs from Bru¨nnichs guillemots) from the same area were also analyzed for organochlorines. The autopsy of the birds did not reveal any specific cause of death. The following chlorinated pesticides were analyzed: hexachlorobenzene (HCB), hexachlorocyclohexanes (α-, β-, γ-HCH), chlordanes (oxychlordane, trans -nonachlor, heptachlor and heptachlor epoxide), the drin group (aldrin, dieldrin) and the DDT group ( o,p′, p,p′DDT, DDD and DDE). Relatively low hepatic concentrations of dieldrin were found (n.d.−0.17 mg/kg wet weight (w.w.), mean 0.04), ∑HCH (n.d.−0.14 mg/kg w.w., mean 0.02), HCB (0.03-1.01 mg/kg w.w., mean 0.51), oxychlordane (0.01-1.85 mg/kg w.w., mean 1.05), p,p′DDE (0.81-5.41 mg/kg w.w., mean 2.98), o,p′DDD (0-0.52 mg/kg w.w., mean 0.14) and ∑DDT (0.9-6.25 mg/kg w.w., mean 2.92). Levels of the other chlorinated pesticides were below the quantification level. Very high concentrations of PCBs were found. The ∑PCB (sum of wet weight concentrations of the 21 individual congeners, the IUPAC nos. 28, 52, 74, 99, 101, 110, 118, 114, 153, 105, 141, 138, 183, 128, 187, 156, 157, 180, 170, 194 and 209) in hepatic tissue was 0.8–32.3 mg/kg w.w. (mean 16.0), in brain 0.9–29.5 mg/kg w.w. (mean 14.8), in kidney 0.4–21.4 mg/kg w.w. (mean 9.7) and in muscle 0.5–6.0 mg/kg w.w. (mean 3.1). The concentrations of the individual PCB congeners are also given. Relatively low concentrations of all the organochlorines were found in guillemot eggs, mean concentrations of ∑DDT and PCBs were 0.25 and 0.47 mg/kg w.w., respectively. A toxicological evaluation of the PCB results is difficult; however, it cannot be excluded that PCBs might have contributed to the death of the gulls.

Chlorinated hydrocarbons in seabirds from the Barents Sea area

Abstract This study presents preliminary results on the levels of organochlorines (OCs) in three seabird species: common eider ( Somateria mollissima ), kittiwake ( Rissa tridactyla ) and glaucous gull ( Larus hyperboreus ) from the Barents Sea area, including Frans Josef Land, Ny-A˚lesund, Bjornoya and Hornoya, in July–August, 1991. Kittiwake was the only species collected at all four sampling areas, and all three species were sampled only at Ny-A˚lesund. Samples of liver, fat, muscle and brain tissue were analyzed for chlorinated pesticides, hexachlorobenzene (HCB), hexachlorocyclohexanes (α, β, γ-HCH), chlordanes (oxychlordane, trans -nonachlor and heptachlor epoxide), the DDT group ( op′ , pp′ DDT, DDD and DDE) and the industrial chemical polychlorinated biphenyls (PCBs). In all species, the highest OC levels were found in fat tissue, followed by liver, muscle and brain. PCBs were the major OC contaminants, followed by the DDT group, the chlordane group, HCB and the HCHs. Only low levels of HCHs were found. The lowest mean level of ΣPCB — sum of concentrations of the 19 individual congeners (2.8 μg/kg wet weight (w.w.)) — was found in the liver of juvenile common eider from Frans Josef Land. The highest mean level of ΣPCB (15 980 μg/kg w.w.) was found in the fat of adult glaucous gulls from Ny-A˚lesund. There were no significant geographical trends in OC contamination in the species investigated. However, the OC levels in kittiwake were highest at Bjornoya. The OC contamination levels in seabirds from the Barents Sea region are in general lower in the 1990s than in past decades.

Oxidative capacity of tissues contributing to thermogenesis in eider (Somateria mollissima) ducklings: changes associated with hatching

Summary1.The development of liver and skeletal muscle oxidative capacities during hatching of the common eider (Somateria mollissima) in the Arctic has been investigated by monitoring tissue cytochrome c oxidase activity.2.The specific activity of the liver enzyme did not change as the embryo underwent hatching, nor during subsequent growth of the duckling into adulthood.3.Thigh muscle enzyme specific activity increased by a factor of 3.4 during the 24 h prehatching period, remained elevated for at least 48 h after hatching, and then returned to the embryonic (−24 h) level in adults.4.Histochemically visualized NADH-tetrazolium reductase of a typical red thigh muscle, M. vastus lateralis, showed a distinct increase in activity as the hatching process progressed to completion.5.Electron microscopy of sectioned M. vastus lateralis revealed a dramatic increase in the density of the myofibrillar structure (number of mitochondrial profiles per unit area), and in the surface area of mitochondrial crista membranes in the course of the 48 h interval from 1 day prehatching to 1 day after hatching.6.The significance of these changes for the scaling of thermoregulatory heat generation in the newly hatched eider duckling is discussed.

Strategies of Homeothermy in Eider Ducklings (Somateria Mollissima)

While most nest-dwelling birds depend on parental brooding to maintain normal body temperature(TB) during the first days of life (Riclefs, 1974), nest-fleers appear to rely on endogenous heat (Koskimies and Lahti,1964). We have studied eider ducklings breeding near the Research Station of The Norwegian Polar Institute at Ny Alesund, Svalbard (79° 55′). The young eiders leave the nest once they have dried at the age of 6–8 hours and from then on spend most of their time on the ice-strewn water.

Contaminants in northern fulmars (Fulmarus glacialis) exposed to plastic

Northern fulmars are seabirds which feed exclusively at sea, and as such, they are useful indicators of ocean health. Marine plastic pollution is an ever-increasing and global issue that affects the northern fulmar as they are frequently found to have ingested plastic. In this report we investigate whether the amount of ingested plastic affects the concentration of certain plastic-adsorbed toxicants in their tissues. Marine plastic pollution is a field of utmost importance. It is our hope that this continues to be an area which receives increased attention in order to elucidate the potential harmful effects plastics have on the northern fulmar and ocean health, in general.