385 research outputs found
Heavy metals in Greenland seabirds
From six Greenland districts we report the concentration of Zn, Cd, Hg and Se in muscle (pectoral), liver and kidney for 320 seabirds of the following species: Cepphus grylle, Uria lomvia, Clangula hyemalis, Mergus serrator, Larus glaucoides, L. hyperboreus, Rissa tridactyla, Pagophila eburnea, Fulmarus glacialis, Phalacrocorax carbo and Stercorarius pomarinus.
Concentrations vary widely within species. Yearlings are low in Cd and Hg. Concentrations tend to increase with age. No significant differences between sexes were found.
On a wet weight basis, the Zn concentration in liver and kidney is c. three times that of muscle. Gulls and the fulmar possess significantly more Zn in muscle than do other seabirds. The Cd concentration in liver and kidney is c. 20 and 80 times higher than in muscle, whereas the Hg concentration in liver and kidney is three to five times higher than that of muscle. The Se concentration in liver and kidney is c. five times the muscle concentration. Muscle, liver and kidney concentrations tend to correlate positively for Cd, Hg and Se. For Zn only liver and kidney concentrations correlate mutually.
On a molar basis, the three organs of all species have a large excess of Se over Hg. The intra-organ association of elements is strongest for Zn and Cd in liver and kidney, and for Hg and Se generally. All four elements show consistently higher concentrations in birds from NW and
NE Greenland than in those from S Greenland. For C. grylle from Avanersuaq, NW Greenland, the Cd concentration is twice that of birds from S Greenland, the difference being highly significant. Hg concentrations are not significantly different
Total mercury in hair of polar bears (Ursus maritimus) from Greenland and Svalbard
Concentrations (ppm = ug/g dry weight) of total mercury (Hg) were determined in hair of polar bears (Ursus maritimus) from northwestern Greenland (N = 22; period of sampling: 1978-1989), eastern Greenland (N = 44: 1984-1989) and Svalbard (N = 31; 1980). For subadults (2-6 years of life), adults (7-10 years). and old bears (>10 years), concentrations of total Hg in hair were not found to be dependent on age or sex. A decreasing trend in Hg concentrations was found from west to east. The mean concentrations of total Hg in hair (cubs of the year and yearlings excluded) were: northwestern Greenland, x = 8.38 ppm (min.-max.: 4.71-14.19 ppm. N = 21); eastern Greenland: x = 4.58 ppm (min.-max.: 2.50-8.83 ppm. N = 41); and Svalbard, x = 1.98 ppm (min.-max.: 1.02-4.55 ppm, N = 29). Concentrations found in northwestern Greenland were similar to those reported by others from the hair of polar bears sampled within management zone F of the eastern Canadian High Arctic. Concentrations of total Hg in polar bear hair from eastern Greenland were similar to concentrations found by others in contemporary (1988) material collected during spring in western Svalbard. However, the mean concentration of total Hg in the 1980 Svalbard material, which was collected during July-September, was significantly lower than concentrations found in samples taken during late winter and spring in eastern Greenland and at Svalbard, respectively. Presumably the relatively low concentrations found in the 1980 Svalbard sample arc attributable to the period of moult and hence a larger proportion of newly grown hair in the individual samples. In a subsample consisting of internal tissues from 19 polar bears from eastern Greenland (1984-1987), concentrations of total Hg in hair correlated positively with concentrations of total Hg (wet weight) in muscle (N = 6), liver (N = 19) and kidney (N = 19) tissue. For liver and kidney tissue these relationships were statistically significant
A note on the diet of narwhals (Monodon monoceros) in Inglefield Bredning (NW Greenland)
The contents of 35 narwhal (Monodon monoceros) stomachs were obtained from the Inuit hunt in Inglefield Bredning (NW Greenland) in the open-water seasons of 1984 and I 985. Questions concerning narwhal feeding habits were addressed by relating lengths of otoliths and invertebrate remains to the known lengths and weights of fishes and invertebrate species prior to digestion, and by assessing the number and volume of each prey species represented by the stomach contents. The 48 kg (wet weight) of stomach contents examined consisted of 64% arctic cod (Arctogadus glacialis), 15% polar cod (Boreogadus saida), 19% unidentified gadids and 2% invertebrates
First Confirmed Record of Grey Seals in Greenland
The presence of grey seals has never before been confirmed in Greenland, but on 30 August 2009 a grey seal was photographed near shore in Southeast Greenland (59˚53′ N, 43˚28′ W). The seal was observed within a small group of islands that hosts a harbour seal colony. The following day, a seal that might be a young grey seal was photographed at the same location. Information from Inuit hunters suggests that grey seals periodically visit Greenland, but the pictures taken in summer 2009 are the first solid proof of this seal species in Greenland.La présence de phoques gris n’avait jamais été confirmée au Groenland, mais le 30 août 2009, un phoque gris a été photographié près de la côte sud-est du Groenland (59˚53′ N, 43˚28′ O). Le phoque a été observé au sein d’un petit groupement d’îles où se tient une colonie de phoques communs. Le lendemain, un phoque qui était peut-être un jeune phoque gris a été photographié au même endroit. D’après les chasseurs inuits, les phoques gris se rendraient périodiquement au Groenland, mais les photographies prises à l’été 2009 constituent les premières preuves tangibles de la présence de cette espèce de phoque au Groenland
Occurrence of narwhals (Monodon monoceros) and white whales (Delphiapterus leucas) in East Greenland
Narwhals (Monodon monoceros) have been observed along the east coast of Greenland from Umiiviip Kangertiva (64°10'N, 41 °W) to Kilen (81°N, 13°W). The fjord complexes of Sermilik, Kangerlussuaq and Scoresby Sund are important inshore summering areas. Narwhals occur in these fjords from ice breakup in May-July until new ice forms in September-November. Narwhals also occur at the entrances to these fjords during winter.
Historical information from whalers indicates that narwhals are present in the pack ice of the Greenland Sea between May and September. Narwhals are believed to be widely scattered in the pack ice between eastern Greenland and Svalbard during winter, and the narwhals in this area may comprise a single population
Are liver and renal lesions in East Greenland polar bears (Ursus maritimus) associated with high mercury levels?
BACKGROUND: In the Arctic, polar bears (Ursus maritimus) bio-accumulate mercury as they prey on polluted ringed seals (Phoca hispida) and bearded seals (Erignathus barbatus). Studies have shown that polar bears from East Greenland are among the most mercury polluted species in the Arctic. It is unknown whether these levels are toxic to liver and kidney tissue. METHODS: We investigated the histopathological impact from anthropogenic long-range transported mercury on East Greenland polar bear liver (n = 59) and kidney (n = 57) tissues. RESULTS: Liver mercury levels ranged from 1.1–35.6 μg/g wet weight and renal levels ranged from 1–50 μg/g wet weight, of which 2 liver values and 9 kidney values were above known toxic threshold level of 30 μg/g wet weight in terrestrial mammals. Evaluated from age-correcting ANCOVA analyses, liver mercury levels were significantly higher in individuals with visible Ito cells (p < 0.02) and a similar trend was found for lipid granulomas (p = 0.07). Liver mercury levels were significantly lower in individuals with portal bile duct proliferation/fibrosis (p = 0.007) and a similar trend was found for proximal convoluted tubular hyalinisation in renal tissue (p = 0.07). CONCLUSION: Based on these relationships and the nature of the chronic inflammation we conclude that the lesions were likely a result of recurrent infections and ageing but that long-term exposure to mercury could not be excluded as a co-factor. The information is important as it is likely that tropospheric mercury depletion events will continue to increase the concentrations of this toxic heavy metal in the Sub Arctic and Arctic marine food webs
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