Search Results - (Author, Cooperation:R. W. Furness)

2011-12-24

American Association for the Advancement of Science (AAAS)

0036-8075

1095-9203

Biology

Chemistry and Pharmacology

Computer Science

Medicine

Natural Sciences in General

Physics

Animals ; Biomass ; Birds/*physiology ; Charadriiformes/*physiology ; *Ecosystem ; Female ; Fisheries ; *Fishes ; Food ; Food Chain ; Male ; Nonlinear Dynamics ; Population Density ; Population Dynamics ; Predatory Behavior ; *Reproduction ; Seawater ; Statistics, Nonparametric

1432-0703

Springer Online Journal Archives 1860-2000

Energy, Environment Protection, Nuclear Power Engineering

Medicine

Abstract Feathers of Audouin's gull chicks from three Aegean island areas (north Dodecanese, Cyclades, Kythera) Greece, were sampled in 1997 and 1998 and analyzed for mercury. Mean concentrations varied from 0.94 μg/g (Lipsos, Dodecanese, 1998) to 2.14 μg/g (Paros, Cyclades, 1998). Significant differences between years occurred in some regions (Lipsos, Fourni) but not in others (Paros). Within each year, especially in 1998, mean mercury concentrations differed among colonies. Results did not support the prediction that mercury levels would be higher in the north Dodecanese area due to the proximity of the polluted Menderes delta. There was no relationship between estimated chick age and feather mercury contents (r =−0.04, NS). Detected mercury levels do not seem to pose any toxic hazard to the Aegean Audouin's gull populations. However, the ease of sampling from gulls indicates that they may be a useful biomonitor of mercury contamination in this region.

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1432-0800

Springer Online Journal Archives 1860-2000

Energy, Environment Protection, Nuclear Power Engineering

Medicine

Electronic Resource

1432-0703

Springer Online Journal Archives 1860-2000

Energy, Environment Protection, Nuclear Power Engineering

Medicine

Abstract. Mercury concentrations were measured in feathers of little egret and night heron chicks and in their prey in the Axios Delta, Greece. Significantly higher concentrations occurred in night heron than in little egret in 1993. In the night heron the mercury content of feathers was negatively correlated to the size of chicks, possibly due to inhibition of growth. Mercury concentrations were higher than reported for heron feathers in seriously polluted sites in North America and Japan, but the toxic hazard is unclear. Diets differed considerably between the two species due to use of different foraging habitats and this seems responsible for different mercury contents of feathers. Mercury concentrations in the pumpkinseed sunfish Lepomis gibbosus, goldfish Carrassius auratus, and in dragonfly Odonata larvae were the highest among the prey categories. Frogs and water beetles Dytiscidae had moderate concentrations whereas saltwater fish and terrestrial prey had very low mercury concentrations. The implication is that the deltaic marshes are the habitat most polluted with mercury. Night heron chick feathers, freshwater fish and dragonfly larvae could be used to monitor mercury contamination in this region, but use of bird feathers alone could give misleading results if changes in diet occurred.

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1433-2981

Key words:Great skua – Normal haematology – Pollution threat – Seabird

Springer Online Journal Archives 1860-2000

Medicine

Abstract: Routine haematological investigations were carried out on 102 wild adult great skuas Catharacta skua. No sex- or age-related differences were detected in any of the parameters measured. There are very few sets of haematological reference ranges published for seabirds from the northeastern Atlantic. Given the recent pollution threats in this region, the reference ranges presented for this species could be a valuable tool in future conservation efforts.

Electronic Resource

1432-2056

Springer Online Journal Archives 1860-2000

Biology

Abstract Mercury concentrations in albatrosses and some other large procellariiforms are very much higher than found in other groups of seabirds. Analysis of mercury concentrations in feather samples collected prior to 1950 and after this date showed slight, but significant, increases in three out of ten sub-Antarctic procellariiform species. The lack of widespread and pronounced increases in mercury concentrations in procellariiforms between these periods may indicate that industrial and agricultural emissions of mercury in the southern hemisphere have been relatively minor and the high concentrations are predominantly due to natural processes. Mercury concentrations were relatively consistent between body feathers of individuals, and showed no variation related to adult age (in years). Within species, mercury concentrations tended to be highest in New Zealand populations and lowest in Falkland Island and South Georgia populations. Mercury concentrations also varied among species, but not in a way that could be related to diet.

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1432-0703

Springer Online Journal Archives 1860-2000

Energy, Environment Protection, Nuclear Power Engineering

Medicine

Abstract Distribution of mercury between tissues was investigated in black-headed gull (Larus ridibundus) chicks fed doses of methyl mercury. Mercury accumulated differentially in the internal tissues, concentrations in the kidney exceeding those in the liver, which in turn exceeded those in the muscle. All feather types contained higher mercury concentrations than internal tissues. For each dose group, there was a progressive and pronounced reduction in the concentrations of mercury found in the primary feathers as the growth sequence progressed. The amount of mercury given to the birds affected the proportion of mercury deposited in the kidney, carcass, and primaries. The amount of mercury administered had no effect on the proportion of mercury excreted either in the faeces or the feathers. 71% of the doses given was excreted over the fledging period, and 49% of the dose was found in the plumage. These figures allow a more quantitative approach to measuring mercury pollution.

Electronic Resource

1432-0703

Springer Online Journal Archives 1860-2000

Energy, Environment Protection, Nuclear Power Engineering

Medicine

Abstract Eggs, feathers (down, body feathers from side/shoulder and back) and some dead chicks (liver) from broods of three species, herring gull (Larus argentatus), black-headed gull (Larus ridibundus), and common tern (Sterna hirundo) from the German North Sea coast were collected to study intersibling differences in mercury contamination and elimination into the growing feathers. The mercury contamination in eggs, feathers, and liver of the terns was about four times that of the gulls; black-headed gulls had lowest mercury concentrations. The body feathers grown when the chicks became older had lower mercury levels than down in the more contaminated species (11% lower in herring gulls, 49% in common terns), indicating the advancing decontamination of the body by the plumage development. The elimination of mercury was greater in chicks with higher mercury levels. Down of the first hatched herring gull and common tern chick contained more mercury than down of the siblings hatched later, because of its higher burden derived from the first laid egg.

Electronic Resource

1432-0703

Springer Online Journal Archives 1860-2000

Energy, Environment Protection, Nuclear Power Engineering

Medicine

Abstract Levels of total mercury were determined in body feathers of 257 seabirds belonging to seven species from the Azores Archipelago, Mid-North Atlantic Ocean. Mercury levels in adult birds showed highly significant inter-specific variations. Median levels were higher in small petrels (Madeiran storm petrel=12.5 μg/g; Bulwer's petrel=22.1 μg/g) than in shearwaters (Little shearwater=2.1 μg/g; Cory's shearwater=6.0 μg/g) and terns (Roseate tern=2.0 μg/g; Common tern=2.3 μg/g). Such inter-specific variability is discussed in relation to biological factors that may influence mercury dynamics in birds. Intra-specific variations in mercury levels were also found. Mercury levels were significantly lower in chicks than in adults of Cory's shearwater, Roseate tern and Common tern. The levels in chick feathers were 60–70% of those in adult feathers. In Cory's shearwater and the terns (Roseate and Common combined), mercury levels decreased significantly with increasing age of chicks. Mercury levels in adult Madeiran storm petrel showed pronounced seasonal variation, being about 50% lower in Spring breeders than in Autumn breeders. Mercury levels are compared with levels reported for seabird populations of the same or related species, from a variety of regions. The use of bird feathers to monitor mercury in the marine environment is briefly discussed.

Electronic Resource

1432-0703

Springer Online Journal Archives 1860-2000

Energy, Environment Protection, Nuclear Power Engineering

Medicine

Abstract. Metallothionein, cadmium, zinc, copper, and mercury concentrations were measured in adult lesser black-backed gulls, Larus fuscus; and metallothionein, cadmium, zinc, and copper concentrations were measured in fledgling Cory's shearwaters, Calonectris diomedea. In gulls, metallothionein was positively correlated with cadmium (kidney r=0.83, liver r=0.46), zinc (kidney r=0.46, liver r=0.37), and copper (kidney r=0.28, liver r=0.34). Mercury levels in lesser black-backed gulls showed no correlations with metallothionein or with any other metal. In shearwaters metallothionein was positively correlated with cadmium in the kidney (r=0.41) but not in liver, zinc in kidney (r=0.43) and liver (r=0.52), and copper in kidney (r=0.55) but not in liver. Cadmium levels were the most important factor determining tissue metallothionein concentrations in adult lesser black-backed gulls demonstrating the role of metallothionein in heavy metal detoxification. In fledgling Cory's shearwaters, the most important factor in determining metallothionein concentrations in kidney was copper concentrations, and in liver, zinc concentrations. During the latter phases of chick growth high levels of zinc are required for feather development, and at this time the binding of cadmium may be masked by the presence of a large amount of zinc- and copper-bound metallothionein. These results illustrate disparate roles of metallothionein, the levels of which will be in a state of flux both seasonally and annually.

Electronic Resource

1432-0703

Springer Online Journal Archives 1860-2000

Energy, Environment Protection, Nuclear Power Engineering

Medicine

Abstract Metallothionein, cadmium, zinc, copper, and mercury concentrations were measured in adult lesser black-backed gulls, Larus fuscus; and metallothionein, cadmium, zinc, and copper concentrations were measured in fledgling Cory's shearwaters, Calonectris diomedea. In gulls, metallothionein was positively correlated with cadmium (kidney r=0.83, liver r=0.46), zinc (kidney r=0.46, liver r=0.37), and copper (kidney r=0.28, liver r=0.34). Mercury levels in lesser black-backed gulls showed no correlations with metallothionein or with any other metal. In shearwaters metallothionein was positively correlated with cadmium in the kidney (r=0.41) but not in liver, zinc in kidney (r=0.43) and liver (r=0.52), and copper in kidney (r=0.55) but not in liver. Cadmium levels were the most important factor determining tissue metallothionein concentrations in adult lesser black-backed gulls demonstrating the role of metallothionein in heavy metal detoxification. In fledgling Cory's shearwaters, the most important factor in determining metallothionein concentrations in kidney was copper concentrations, and in liver, zinc concentrations. During the latter phases of chick growth high levels of zinc are required for feather development, and at this time the binding of cadmium may be masked by the presence of a large amount of zinc- and copper-bound metallothionein. These results illustrate disparate roles of metallothionein, the levels of which will be in a state of flux both seasonally and annually.

Electronic Resource

1432-0703

Springer Online Journal Archives 1860-2000

Energy, Environment Protection, Nuclear Power Engineering

Medicine

Abstract Total mercury concentrations were determined in samples of body feathers from a range of common seabird species breeding at L»trabjarg, northwest Iceland, St. Kilda, Foula and the Firth of Forth, Scotland and Bleiksøy, Syltefjord, and Hornøy, Norway. Seabirds from L»trabjarg generally exhibited the highest mercury concentrations, with a trend of decreasing mercury concentrations in a southwest to northeast direction in seabirds at the other colonies; seabirds at Hornøy were generally found to have the lowest mercury concentrations. Some species at the Firth of Forth exhibited relatively elevated mercury concentrations compared to those at Foula and Norwegian sites. Inter-colony differences in diet were thought to be relatively small for most species and unlikely to account for the range of mercury concentrations measured in the seabirds (L»trabjarg: lowest arithmetic mean mercury concentration in common guillemots Uria aalge, 1.6 μg/g, s.d.=0.6, n=45; highest arithmetic mean mercury concentration in kittiwakes Rissa tridactyla, 5.5 μg/g, s.d.=1.7, n=36). The oceanic transport of mercury, together with the effects of anthropogenic inputs of mercury to the northeast Atlantic, and the removal of mercury from the water column via biological activity are discussed as influential factors determining the observed patterns of mercury concentration in seabirds.

Electronic Resource

1432-0703

Springer Online Journal Archives 1860-2000

Energy, Environment Protection, Nuclear Power Engineering

Medicine

Abstract Mercury, cadmium, zinc, and copper concentrations were analyzed in three samples of common guillemot (in April, June, and November). Levels measured were uniformly low, and not enough to have any toxic effects. Adult guillemots had significantly more cadmium in their livers and kidneys than juveniles, with juvenile levels ranging from 25% to 89% of adult levels. Mercury concentrations in liver and kidney were also higher in adults. Juvenile levels represented from 80% to 94% of adults, but there were no age differences in feather and muscle mercury. Mercury levels declined throughout the year in internal tissues from April through June to November. There was a strong seasonal fluctuation in cadmium levels in liver and kidney, rising significantly between April and June and declining again from June to November. These changes were apparent in both adult and juvenile birds. The influences of seasonal processes (namely breeding and moult) and seasonal dietary differences as causative factors in the changes in metal burdens are discussed. These findings have implications for the use of seabirds as monitors of heavy metals in the marine environment.

Electronic Resource

1476-4687

Nature Archives 1869 - 2009

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

[Auszug] We tested the idea of prey depeletion by considering spatial distribution and sizes of seabird colonies, as a direct demonstration would require an expensive marine sampling programme. If Ashmole's model is correct, then in an area of uniform mean productivity, colony size should be strongly and ...

Electronic Resource

1573-2932

Springer Online Journal Archives 1860-2000

Energy, Environment Protection, Nuclear Power Engineering

Abstract The oceans play a major role in global cycling of mercury and widespread contamination of marine ecosystems has been demonstrated in recent years. Monitoring mercury in the marine environment is a priority and biomonitoring has featured prominently in this respect. Seabirds, as top predators, present high mercury levels due to food chain amplification and thus will reflect slight variations in environmental mercury and its hazards to humans better than do most invertebrates and cold blood vertebrates. There is experimental evidence that levels of mercury in seabirds show a dose-response relationship, so that increased contamination of the environment causes a corresponding increase in the level in birds. This coupled with current knowledge on the dynamics of mercury in birds gives a good basis for the use of seabird as monitors of mercury. Internal tissues, blood, eggs, feathers and chicks have been used as monitoring units. Feathers are the most attractive amongst them. They are both chemically and physically stable, accumulate higher mercury levels than other tissues and their sampling is non-destructive. However, it is essential to sample a consistent feather area from all birds to minimise the effects of moult and body feathers are the most adequate. Feathers from birds in museum collections offer a great potential for the study of synoptic geographical and historical of changes in mercury levels on a global scale with large sample sizes. For example, studies with time series of feather samples from seabirds provide evidence of a 3-fold increase of mercury contamination in the marine ecosystem of North-eastern Atlantic over the last 100 years and little increase in mercury contamination in the Southern hemisphere during the same period.

Electronic Resource

1573-2959

age ; biomonitoring ; heavy metals ; seabirds

Springer Online Journal Archives 1860-2000

Energy, Environment Protection, Nuclear Power Engineering

Abstract The effects of age on cadmium concentrations was investigated in Cory's shearwater, Calonectris diomedea, Lesser black-backed gull, Larus fuscus, and great skuas, Catharacta skua. There was no evidence for the continued accumulation of cadmium with increasing adult age. Adult shearwaters did have higher concentrations of cadmium compared to young fledglings, but there was no significant difference between cadmium concentrations in adult and sub-adult gulls. In addition, the sample of great skuas were of known age (3–22 yrs old) and showed no evidence of increasing cadmium concentrations with adult age in liver or kidney. However, it is possible that age accumulation of cadmium in great skuas was masked by individual dietary preferences overriding the effects of increasing age. It is often assumed that cadmium concentrations continue to accumulate with increasing adult age, but seabirds may have evolved some as yet unknown mechanism for excretion or more rapid turnover of cadmium than previously thought. The implications of this for the use of seabirds as biomonitors is discussed.

Electronic Resource

1432-0762

Springer Online Journal Archives 1860-2000

Biology

Summary Many birds accumulate fat reserves prior to departure on long distance migration. Since there will be an increased food requirement during the pre-migratory period, it is to be expected that more time will be invested in foraging, at the expense of other activities. The allocation of time to anti-predatory behavior in migratory ruddy turnstones (adults) was found to decrease prior to migration (Fig. 1); non-migratory individuals (juveniles) showed no decrease over the same time period (Fig. 2). This is interpreted as a change in the optimal adult behavior, the cost of a reduced rate of resource accumulation outweighing the additional risk of predation which results from the decrease in vigilance.

Electronic Resource

1438-3888

Springer Online Journal Archives 1860-2000

Biology

Abstract Once the moult patterns have been taken into account, feather methylmercury levels can be used to accurately measure the mercury burdens of seabirds. We used body feathers from live seabirds and from museum collections to examine geographical and temporal patterns of mercury contamination in the North Sea. This approach identifies an increase in mercury concentrations in seabirds of the German North Sea coast during the last 100 years, especially high levels during the 1940s, and reduced contamination in the last few years. Comparisons among populations suggest that some increases in mercury levels are predominantly due to local pollution inputs, as on the German coast, while in other areas deposition from jet stream circulation of global contamination may be the major contributor. Mercury levels are far higher in seabirds from the German North Sea coast than in populations from the north and west North Sea or from most areas of the North Atlantic. We advocate the use of museum collections of birds for studies of long-term changes in levels of mercury contamination.

Electronic Resource

1573-3017

mercury ; eggs ; feathers ; quail ; dose-response

Springer Online Journal Archives 1860-2000

Energy, Environment Protection, Nuclear Power Engineering

This paper describes differences in the excretion of methyl mercury between male and female Quail Coturnix coturnix after a single dose. Since feathers are often used to monitor mercury pollution it is important to take into account biases in feather mercury levels that may arise as a result of mercury loss through egg-laying. Evidence is presented to support the use of bird eggs to sample for environmental mercury contamination. Birds were monitored up to twelve weeks after administration. Mercury concentrations in the kidney exceeded those in the liver which exceeded those in the pectoral muscle. Significant differences in mercury levels between male and female birds were found up to eight weeks after administration. Mercury was initially distributed through most of the internal tissues and was lost relatively slowly in a negative exponential manner. Mercury loss through excretion differed between the sexes for the first eight weeks after mercury administration. Initial mercury concentration in eggs was 3.5 μg g-1 but no mercury was detected in eggs five weeks after the dose was administered. At this point over 40% of the females' intake had been lost into the eggs.

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