Limits...
Properties of blood, porphyrins, and exposure to legacy and emerging persistent organic pollutants in surf scoters (Melanitta perspicillata) overwintering on the south coast of British Columbia, Canada.

Wilson LK, Harris ML, Trudeau S, Ikonomou MG, Elliott JE - Arch. Environ. Contam. Toxicol. (2010)

Bottom Line: In addition, a low proportion of lymphocytes in individuals across locations in early spring samples was associated with poor body condition.The apparent loss of fitness just prior to the onset of northerly migrations to breeding grounds is of particular concern.Compromised health of mature birds at this point in the season might impact negatively on the productivity and survival of some individuals, particularly those overwintering in Howe Sound.

View Article: PubMed Central - PubMed

Affiliation: Canadian Wildlife Service, Pacific Wildlife Research Centre, Environment Canada, 5421 Robertson Rd., RR1, Delta, BC, V4K 3N2, Canada.

ABSTRACT
The surf scoter (Melanitta perspicillata) is a little-studied species of North American sea duck. Estimates suggest it has experienced a precipitous decline in breeding numbers over the latter half of the past century. To investigate the potential role of contaminant uptake and toxicity in the population decline, this study undertook to measure blood chemistry, porphyrin concentrations, EROD, and organic contaminants in mature surf scoters wintering in the Strait of Georgia, BC, Canada. Hepatic organochlorine pesticide, polychlorinated dibenzo-p-dioxin, polychlorinated dibenzofuran, polychlorinated biphenyl (PCB), polybrominated diphenyl ether, and nonylphenol concentrations were relatively low; for example, SigmaTEQs (toxic equivalents) for PCBs, dioxins, and furans combined ranged from 4.7 ng/kg wet weight in reference-site (Baynes Sound) birds to 11.4 ng/kg wet weight in birds from Vancouver Harbour. Nonetheless, elevated EROD activity indicated that birds in Howe Sound were responding to an Ah-receptor-mediated stressor, which was also affecting hematocrit values and possibly vitamin A status. In addition, a low proportion of lymphocytes in individuals across locations in early spring samples was associated with poor body condition. The apparent loss of fitness just prior to the onset of northerly migrations to breeding grounds is of particular concern. Compromised health of mature birds at this point in the season might impact negatively on the productivity and survival of some individuals, particularly those overwintering in Howe Sound.

Show MeSH

Related in: MedlinePlus

The variable composition of hepatic concentrations of total porphyrins, expressed as proportion of protophorphyrin relative to proportion of coproporphyrin, in adult male surf scoters collected during the late fall 1998 (December) and early spring 1999 (2 March) in the Strait of Georgia, BC
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2908456&req=5

Fig1: The variable composition of hepatic concentrations of total porphyrins, expressed as proportion of protophorphyrin relative to proportion of coproporphyrin, in adult male surf scoters collected during the late fall 1998 (December) and early spring 1999 (2 March) in the Strait of Georgia, BC

Mentions: The assessment of seasonal changes in hepatic porphyrin concentrations was impeded by the existence of significant interactions between collection date and the relevant covariate (protoporphyrin, p = 0.02, or uroporphyrin, p = 0.0003). This suggested that the metabolism of porphyrin changed between fall and spring. A graphic examination of the proportionality of single porphyrins to total porphyrins (Σ[uroporphyrin + hepta- + hexa- + penta-carboxylic porphyrins + coproporphyrin + protoporphyrin]) supported and expanded upon this statistical finding, as it indicated that a number of spring samples showed greater relative concentrations of coproporphyrin (Fig. 1). This made the examination of seasonal changes in absolute concentrations of single porphyrins irrelevant.Fig. 1


Properties of blood, porphyrins, and exposure to legacy and emerging persistent organic pollutants in surf scoters (Melanitta perspicillata) overwintering on the south coast of British Columbia, Canada.

Wilson LK, Harris ML, Trudeau S, Ikonomou MG, Elliott JE - Arch. Environ. Contam. Toxicol. (2010)

The variable composition of hepatic concentrations of total porphyrins, expressed as proportion of protophorphyrin relative to proportion of coproporphyrin, in adult male surf scoters collected during the late fall 1998 (December) and early spring 1999 (2 March) in the Strait of Georgia, BC
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2908456&req=5

Fig1: The variable composition of hepatic concentrations of total porphyrins, expressed as proportion of protophorphyrin relative to proportion of coproporphyrin, in adult male surf scoters collected during the late fall 1998 (December) and early spring 1999 (2 March) in the Strait of Georgia, BC
Mentions: The assessment of seasonal changes in hepatic porphyrin concentrations was impeded by the existence of significant interactions between collection date and the relevant covariate (protoporphyrin, p = 0.02, or uroporphyrin, p = 0.0003). This suggested that the metabolism of porphyrin changed between fall and spring. A graphic examination of the proportionality of single porphyrins to total porphyrins (Σ[uroporphyrin + hepta- + hexa- + penta-carboxylic porphyrins + coproporphyrin + protoporphyrin]) supported and expanded upon this statistical finding, as it indicated that a number of spring samples showed greater relative concentrations of coproporphyrin (Fig. 1). This made the examination of seasonal changes in absolute concentrations of single porphyrins irrelevant.Fig. 1

Bottom Line: In addition, a low proportion of lymphocytes in individuals across locations in early spring samples was associated with poor body condition.The apparent loss of fitness just prior to the onset of northerly migrations to breeding grounds is of particular concern.Compromised health of mature birds at this point in the season might impact negatively on the productivity and survival of some individuals, particularly those overwintering in Howe Sound.

View Article: PubMed Central - PubMed

Affiliation: Canadian Wildlife Service, Pacific Wildlife Research Centre, Environment Canada, 5421 Robertson Rd., RR1, Delta, BC, V4K 3N2, Canada.

ABSTRACT
The surf scoter (Melanitta perspicillata) is a little-studied species of North American sea duck. Estimates suggest it has experienced a precipitous decline in breeding numbers over the latter half of the past century. To investigate the potential role of contaminant uptake and toxicity in the population decline, this study undertook to measure blood chemistry, porphyrin concentrations, EROD, and organic contaminants in mature surf scoters wintering in the Strait of Georgia, BC, Canada. Hepatic organochlorine pesticide, polychlorinated dibenzo-p-dioxin, polychlorinated dibenzofuran, polychlorinated biphenyl (PCB), polybrominated diphenyl ether, and nonylphenol concentrations were relatively low; for example, SigmaTEQs (toxic equivalents) for PCBs, dioxins, and furans combined ranged from 4.7 ng/kg wet weight in reference-site (Baynes Sound) birds to 11.4 ng/kg wet weight in birds from Vancouver Harbour. Nonetheless, elevated EROD activity indicated that birds in Howe Sound were responding to an Ah-receptor-mediated stressor, which was also affecting hematocrit values and possibly vitamin A status. In addition, a low proportion of lymphocytes in individuals across locations in early spring samples was associated with poor body condition. The apparent loss of fitness just prior to the onset of northerly migrations to breeding grounds is of particular concern. Compromised health of mature birds at this point in the season might impact negatively on the productivity and survival of some individuals, particularly those overwintering in Howe Sound.

Show MeSH
Related in: MedlinePlus