Accumulation of selenium and lack of effects on American dippers and spotted sandpipers

We compared selenium concentrations in the eggs of 2 riverine waterbirds, American dippers (Cinclus mexicanus) and spotted sandpipers (Actitis macularia), with measures of productivity: clutch size, brood size, and health status of eggs and young. In American dippers, the mean egg selenium concentration from the exposed areas was slightly higher (1.08 μg/g ww) than in the reference areas (0.95 μg/g ww), but this difference was not significant. For spotted sandpipers, the mean egg selenium concentration in the exposed areas was 2.2 ± 0.5 μg/g ww and in the reference areas, 1.2 ± 0.14 μg/g ww. This difference was significant, and was close to published toxicity thresholds. There were no significant differences between reference areas and exposed groups for clutch size, hatching success, or fledging success in either species. There was also no correlation between selenium concentrations and eggs laid, eggs hatched or hatchlings fledged in either species. There was no significant difference in health status of eggs (viable, inviable, or dead embryo) between the exposed and reference sites, and no relationship between selenium concentrations and the eggs’ health status. Although selenium was being taken up in spotted sandpipers, it was below levels that would affect reproduction or productivity.Non UBCUnreviewedOthe