Feather Concentrations Research Articles

An epizootic of common loons in coastal waters of North Carolina: Concentrations of elemental contaminants and results of necropsies

AbstractA 1993 die‐off of common loons (Gavia immer) in the coastal waters of North Carolina was investigated with emphasis on comparing mercury, selenium, arsenic, and lead between birds from the epizootic and reference specimens. Die‐off specimens were emaciated but contained no ingested foreign bodies and no lesions suggestive of infectious disease. Results of bacteriology, virology, parasitology, and botulism testing were unremarkable. The geometric mean concentrations (wet weight) of liver mercury (10.9 ppm), and arsenic (0.96 ppm) did not differ between specimens from the die‐off and reference loons from the same area that died of other causes. The geometric mean liver selenium concentration of die‐off specimens (10.4 ppm) was significantly higher than that of reference loons. Liver lead concentrations were < 0.20 ppm in all but one sample (5.83 ppm). The geometric mean mercury concentration in the primary remiges of die‐off specimens (5.44 ppm dry weight) was significantly lower than in reference birds. Liver mercury significantly correlated with liver selenium on a molar concentration basis. We interpret the range of liver mercury concentrations in birds from the epizootic, similar liver mercury concentrations in reference loons, and higher mercury concentrations in reference loon feathers as evidence that factors other than mercury were primarily responsible for the emaciation diagnosed as the cause of mortality.

Heavy metal, organochlorine pesticide, and PCB residues in eggs and feathers of herons breeding in northern Italy.

We report on organochlorine pesticide and PCB concentrations in eggs of the little egret, Egretta garzetta, and the black-crowned night-heron, Nycticorax nycticorax, collected in 1993-1994, and on mercury, cadmium, and lead concentrations in feathers of 20-day-old nestlings collected from the same nests in 1994, from heronries near Pavia, northern Italy. Organochlorine pesticide and PCB residues were lower than those commonly associated with mortality and reduced reproductive success. As population levels of the species studied are not declining, these contaminants appear to have no significant adverse effect on reproduction in the heronries studied. DDE levels have decreased markedly in heron eggs since 1978. However, the presence of both DDT and beta-HCH, albeit at low levels, is notable, given that these compounds were banned in Italy in 1978 and 1988, respectively. Relatively high levels of Hg, Cd, and Pb in feathers suggest birds in their colonies are exposed to these contaminants, although both Cd and Pb may relate more to external than to internal contamination.

Mercury accumulation in the muscles and feathers of pheasants, Phasianus colchicus (L. 1758)

Mercury concentrations were determined in muscles and feathers of 58 cock pheasants. Birds were collected from seven different polluted sites in southern Poland in 1987. The mercury concentrations in the muscle ranged from 0.010 to 0.026 mug g dry mass. The significantly highest values were found in muscle samples from Przylasek and Przemysl. The levels found in the flight feathers were higher than in breast feathers. Average concentrations in flight feathers ranged from 0.050 mug g (Przemysl) to 0.240 mug g dry mass (Przylasek). © Rapid Science 1998

Seabirds as monitors of the marine environment

Many studies have shown that seabirds are sensitive to changes in food supply, and therefore have potential as monitors of fish stocks. For most seabird species breeding parameters suitable for biomonitoring have yet to be measured over a wide range of prey densities. However, it is clear that responses vary among species and care must be taken when interpreting seabird data as a proxy for fish abundance. For many years seabirds have also been used as monitors of pollution, especially oil pollution. Beached bird surveys provide important evidence of geographical and temporal patterns, and, for example, show consistent declines in oil release into the southern North Sea over the last 15 years. Analysis of oil on birds can now permit fingerprinting of sources, allowing prosecution of polluters. As predators high in marine food webs, seabirds also have potential as monitors of pollutants that accumulate at trophic levels. Recent work on mercury in seabirds has permitted an analysis of spatial patterns and of the rates of increase in mercury contamination of ecosystems over the last 150 years, since mercury concentrations in feathers of museum specimens can be used to assess contamination in the birds when they were alive. Surprisingly, pelagic seabirds show higher increases than most coastal ones, and increases have been greatest in seabirds feeding on mesopelagic prey. This seems to relate to patterns of methylation of mercury in low-oxygen, deeper water. Accurate measurement of long-term trends in mercury contamination depend on the assumption that seabird diet composition has not changed. This can be assessed by analysis of stable isotopes of N and C from the same feathers used for mercury measurement, a technique that also permits the monitoring of trophic status over time or between regions. While high mercury contamination of seabirds in the southern North Sea is unsurprising, we cannot yet explain certain unexpected results, such as high levels in seabirds from north Iceland compared with those from south Iceland or Scotland.

Heavy metal and selenium concentrations in feathers of egrets from Bali and Sulawesi, Indonesia.

Herons and egrets are ideal organisms to use asindicators of heavy metal exposure in an ecosystem because different speciesfeed at different levels of the food chain and live in both coastal andinland habitats. This paper reports on the concentration of heavy metals andselenium in the feathers of cattle egrets Bubulcus ibis that wereexamined from nesting and roosting sites in Bali and Sulawesi, Indonesia, andin feathers of little egrets Egretta garzetta and intermediate egretsE. intermedia from the same colony in Bali. Mercury and manganeseconcentrations were significantly higher in cattle egrets from Bali comparedto Sulawesi, but otherwise there were no significant differences. There weresignificant differences in lead, cadmium and mercury among the three egretspecies nesting on Bali: 1) the cadmium and mercury concentrations related tosize and trophic level (insectivorous cattle egrets had the lowestconcentrations, fish-eating intermediate egrets had the highestconcentrations), and 2) cattle egrets had significantly lower concentrationsof lead than the other two species. For cattle egrets, secondary flightfeathers had significantly higher levels of cadmium and mercury, and lowerlevels of manganese, than mixed breast and tertiary feathers, reflectingtemporal differences in exposure.

Locational differences in metal concentrations in feathers of Australasian gannet (Morus serrator) in New Zealand

Levels of lead, cadmium, mercury, selenium, manganese and chromium were examined in breast feathers of Australasian Gannets (Morus serrator) from New Zealand waters, where they breed on coastal rocky stacks, islands, and occasionally coastal headlands. There were significant differences in the concentrations of all metals except mercury, with gannets from Ninety Mile Beach having significantly lower levels of all metals than those from the other beaches. Ninety Mile Beach is on the northern tip of the North Island, away from urbanization and industrialization, whereas the other beaches are closer to Auckland, the largest city in New Zealand. The levels of most metals were similar or lower than those reported for feathers from elsewhere around the world. Mercury, however, was at the high end, being exceeded only by raptors and gulls from industrialized countries. Several metal levels were highly correlated, indicating that gannets were usually exposed to several metals at once.

Heavy metal concentrations in feathers of common loons (Gavia immer) in the Northeastern United States and age differences in mercury levels

Feathers serve as a useful, non-destructive approach for biomonitoring some aspects of environmental quality. Birds can eliminate over 90% of their body burden of mercury by sequestration in growing feathers, and they molt their feathers at least annually. Thus mercury concentrations should not vary in avian feathers as a function of age. We tested the null hypothesis that there are no age differences in the concentrations of mercury, lead, cadmium, selenium, copper, chromium and manganese in the feathers of immature and adult common loons Gavia immer from the Northeastern United States where the species is declining. Adults had significantly higher mean levels of mercury (20245 ppb) than immature loons (9677 ppb), but there were no age-related differences for other elements. Even with the small number of immatures, females had significantly higher levels of mercury than males, although the gender difference was not significant for adults.

Metal concentrations in feathers of birds from Papua New Guinea forests: Evidence of pollution

AbstractWe used the feathers of seven species of birds from New Guinea highland forests to examine concentrations of heavy metals and selenium. We tested the null hypotheses that there were no species, food type, or elevation differences in the concentrations of mercury, lead, cadmium, selenium, chromium, and manganese in the feathers of adults. All species had nondetectable levels of mercury (< 10 ppb). There were significant species differences in cadmium, lead, chromium, selenium, and manganese. Common smokey honeyeaters (Melipotes fumigatus, a fruit and flower feeder) had the lowest levels of all metals; blue‐grey robin (Peneothello cyanus, mainly insectivorous) had the highest cadmium and manganese; and several species of birds of paradise (mainly frugivorous) had the highest lead levels. Lead levels were relatively high compared to those reported from feathers of other birds, attributable to the use of leaded gasoline.

Trace metals in primary feathers of the Barn Owl ( Tyto alba guttatus) in The Netherlands

The number of Barn Owls in The Netherlands has been reduced substantially over the last few decades. Death as a result of poisoning seems unlikely, but the pathology of all bird species found dead in The Netherlands between 1975 and 1988 ( n = 15 442) shows that 21% of all the birds were contaminated. However, the most important factor responsible for the decline in Barn Owl numbers in The Netherlands has not yet been established. As a part of a new national protection plan for the Barn Owl, the role of heavy metals has been investigated. Concentrations of heavy metals in the primary feathers of the Barn Owl varied according to their position in the wing; especially As, Sb, Fe and Zn whose concentrations depended on the place of the primary feather in the wing and the part of the vane which is used for the monitoring. The HS7 feather vane appears to provide a good estimate, even though the metal concentrations of this feather are always slightly lower than the concentrations in mixed samples of all ten primaries. It is recommended that they are used as a standard. Many factors affect metal concentrations. Increasing levels with age are found, presumably because metals are stored during growth at the end of the feathers as a method of reducing possible harmful effects. No significant correlations were found between the metal concentrations in the organs and those in the feather. Kidney and liver concentrations are always lower than the generally accepted levels for pathological damage of these organs. Even though metal concentrations in Barn Owl feathers are high compared with those reported for other birds in the Netherlands, it is concluded that Barn Owls are not adversely affected by current levels of heavy metal contamination in The Netherlands.

Long-Term Changes in Mercury Concentrations in Herring Gulls Larus argentatus and Common Terns Sterna hirundo from the German North Sea Coast

1. Mercury concentrations in body feathers of herring gulls Larus argentatus Pontoppidan from the German North Sea coast showed no significant variation among seasons or regions. 2. Concentrations were higher in adults than in juveniles and two times higher after 1940 than in earlier years. Among adult herring gulls, concentrations increased abruptly to a peak of 12 μg g −1 during the 1940s, presumed to be due to high discharges of mercury during the Second World War. Concentrations dropped in the 1950s then increased to a second peak in the 1970s (10 μgg −1 ) before falling in the late 1980s

Melanin Concentrations in Feathers from Wild and Domestic Pigeons

Melanin Concentrations in Feathers from Wild and Domestic Pigeons

Mercury Accumulation in Great Skuas Catharacta skua of Known Age and Sex, and Its Effects Upon Breeding and Survival

(1) Great skuas Catharacta skua Brunnich have among the highest tissue mercury concentrations of British seabirds, and many of the birds breeding on Foula, Shetland in 1988 and 1989 had concentrations well in excess of those known to affect reproduction adversely in some terrestrial bird species. Comparison of mercury concentrations in feathers of great skuas collected before 1900 and in 1988-89 indicates a significant increase during this century, which is assumed to be due to anthropogenic activities (Thompson 1989). (2) Mercury in muscle tissues of great skuas was entirely methyl mercury, whereas approximately half the mercury in liver and kidney tissue was inorganic. Feather mercury concentrations correlated with total mercury concentrations in soft tissues of birds culled during incubation. (3) Mercury concentrations in feathers of adult great skuas on Foula, Shetland were found to be higher than those in feathers of chicks, but were independent of adult age and sex. (4) There was no evidence of accumulation of inorganic mercury in soft tissues with age. This suggests that dietary variation and specialization are more important than age as determinants of mercury concentrations in this species. (5) There was no relationship between diet during the breeding season and feather mercury concentration, either comparing mercury concentrations in different years covering a period of major change in diet at the colony, or comparing different birds with markedly different diets in the same year. Great skuas disperse widely during the winter, and differences in exposure to mercury during this period may be more important than differences in diet during the breeding season. (6) Despite evidence of increased mercury pollution (Thompson 1989), there was no evidence of a relationship between the mercury concentrations of individuals and their breeding performance or survival.

Mercury levels in Bonaparte's gulls (Larus Philadelphia) during autumn molt in the Quoddy region, New Brunswick, Canada

No significant between sex differences were detected in Hg concentrations in primary feathers, pectoral muscle, brain, liver, and kidney tissues of fall migrating juvenile and second-year Bonaparte's gulls (Larus Philadelphia) collected in the Quoddy region. Adults showed sexual differences only in the first 5 primary feathers, and in muscle, kidney and brain. Differences in Hg concentrations among age groups were reflected in the primary feathers and body tissues, but as the molt progressed, Hg concentrations decreased as they converged toward a minimum asymptotic Hg level for each tissue. This suggests that the body burden of Hg was reduced through its redistribution from the body tissues into the growing feathers. Mercury concentrations in premolt head feathers (pre-egg-laying) did not vary significantly between adult females and males, whereas Hg concentrations in postmolt feathers (post-egg-laying) were significantly lower in females, suggesting that egg-laying was also a route for Hg elimination. After the completion of the molt, the new feathers contained most of the body burden of Hg (93.0% in adults).

Variability of cadmium and lead concentrations in bird feathers.

Variability of cadmium and lead concentrations in bird feathers.

Mecury Concentrations in Ten Species of Australian Waterfowl (Family Anatidae)

Total mercury concentrations in wing muscle of 10 species of waterfowl (Anatidae) collected during 1977 and 1978 in south-eastern Australia ranged from 0.08 � 0.04 (mean � SD) g g-1 wet weight in Australian shelduck Tadorna tadornoides and Pacific black duck Anas superciliosa, to 0.17 � 0.08 g g-1 in freckled duck Stictonetta naevosa. No significant differences in concentrations of mercury in muscle were found between sexes or between juvenile and adult birds. Total mercury concentrations in feathers were 3.01 � 0.09 g g-1 dry weight in Pacific black duck and 3.27 � 1.11 g g-1 in grey teal Anas gibberifrons. A significant positive correlation (r= 0.7783; P<0.01) was found between mercury concentrations in wing muscles and feathers of Pacific black duck.

Effects of chronic lead ingestion on reproductive characteristics of ringed turtle doves Streptopelia risoria and on tissue lead concentrations of adults and their progeny

Ringed turtle doves Streptopelia risoria received 0 or 100 μg ml −1 lead in their drinking water for two weeks prior to pairing and throughout a breeding cycle. Lead treatment did not increase the time required to produce eggs, did not disrupt egg production, and disruptions in fertility of eggs were not detected. Testes weights were lower (p < 0·05) in lead treated birds where spermatozoan numbers tended to be lower. Bone lead was higher (p < 0·05) in doves ingesting lead, and females had more than ten times the bone lead concentrations of males. Lead was transmitted from adults to juveniles via the egg and probably by feeding young with crop milk. Progeny of lead-treated parents had higher (p < 0·05) lead concentrations in bones, livers and primary feathers than progeny of controls. Packed cell volumes and body weight gains of juveniles were not disturbed by lead treatment of parents.

Heavy metal concentrations in feathers of ruffed grouse shot by Virginia hunters.

Heavy metal contamination is a continuing problem for populations of wild animals and in environmental management. Those species which inhabit relatively undisturbed environments and are nonmigratory probably present the best opportunities to obtain background concentrations of heavy metals under present day conditions. Work on one such species-the wild turkey (Meleagris gallopava) has been reported earlier. Concentrations of lead, cadmium, nickel, zinc, silver and copper in ruffed grouse (Bonassa umbellus) shot by hunters in Virginia were analyzed.

Status and prospects of eagles in Norway

We investigated the variation in concentrations and profiles of various classes of organohalogenated compounds (OHCs) in different feather types, muscle tissue and preen oil from 15 white-tailed eagle (Haliaeetus albicilla) carcasses from Greenland. The influence of moult patterns and potential external contamination onto the feather surface was examined, while the present study is also the first to investigate the use of body feathers for OHC monitoring. Concentrations of sum polychlorinated biphenyls (PCBs) in feathers from white tailed eagles ranged from 2.3 ng/g in a primary wing feather to 4200 ng/g in body feathers. Using 300 mg of body feathers, almost 50 different OHCs could be quantified and median concentrations in body feathers were 10 fold higher than concentrations in tail feathers (rectrices) or primary wing feathers. Body feathers could be very useful for biomonitoring taking into account their easy sampling, short preparation time and high levels of OHCs. In addition, the effects of confounding variables such as feather size, moult and age are also minimised using body feathers. Correlations with concentrations in muscle tissue and preen oil were high and significant for all feather types (r ranging from 0.81 to 0.87 for sum PCBs). Significant differences in concentrations and profiles of OHCs were found between different primary feathers, indicating that the accumulation of OHCs in feathers varies over the moulting period (maximum three years). Washing of feathers with an organic solvent (acetone) resulted in a significant decrease in the measured concentrations of OHCs in feathers. However, our results indicated that preen oil is probably not the only contributor to the external contamination that can be removed by washing with acetone. Possibly dust and other particles may be of importance and may be sticking to the preened feathers. Rectrices washed only with water showed high and significant correlations with concentrations in muscle and preen oil as well. Washing with acetone therefore does not seem to be of great influence when relating to internal tissue concentrations. We recommend washing feathers only with distilled water in order to remove dirt and dust particles before analysis.