Is selenium affecting body condition and reproduction in boreal breeding scaup, scoters, and ring-necked ducks?
Elevated levels of selenium (Se) have been detected in wintering and spring-staging lesser scaup. Here, we compared spring scaup Se and mercury (Hg) levels to those of ring-necked ducks and white-winged scoters, species exhibiting increasing and decreasing boreal populations, respectively. Mercury concentrations were low in all three species. Geometric mean (95%CI) liver Se concentrations were 6.2 (5.5-7.0), 4.6 (4.0-5.4), and 32.6 (28.4-37.3)mg/kg dry weight (dw) in scaup, ringnecks and scoters, respectively. Only scoter livers (66%) were above 33 mg/kgdw Se. Scaup and ringneck Se levels were unrelated to breeding status or lipid and protein levels; breeding scoters and females with greater lipid mass had higher Se than non-breeders. Egg and follicle concentrations in scaup and scoters were normal (mean [95%CI]=2.3 [1.9-2.6] and 2.4 [2.1-2.7]mg/kgdw, respectively). Overall, we found no support for a relationship between selenium and boreal scaup and scoter declines, and discuss current Se threshold concentrations.
DeVink
Jean-Michel A
JM
Department of Biology, University of Saskatchewan, 112 Science Place, Saskatoon, Saskatchewan S7N 5E2, Canada. jdevink@jacqueswhitford.com
Clark
Robert G
RG
Slattery
Stuart M
SM
Wayland
Mark
M
D000818:Animals; D046090:Anseriformes / Q000502:physiology*; D001947:Breeding; D004781:Environmental Exposure; D004784:Environmental Monitoring / Q000379:methods; D004785:Environmental Pollutants / Q000032:analysis / Q000633:toxicity*; D005260:Female; D008055:Lipids / Q000032:analysis; D008099:Liver / Q000737:chemistry; D008628:Mercury / Q000032:analysis / Q000633:toxicity; D006080:Ovarian Follicle / Q000737:chemistry; D010063:Ovum / Q000737:chemistry; D011506:Proteins / Q000032:analysis; D012621:Seasons; D012643:Selenium / Q000032:analysis / Q000633:toxicity*
D004785:Environmental Pollutants; D008055:Lipids; D011506:Proteins; D008628:Mercury; D012643:Selenium