Lead Exposure of Waterfowl Ingesting Coeur d'Alene River Basin Sediments

Abstract

Feces from tundra swans [Cygnus columbianus (Ord)], Canada geese [Branta canadensis (L.)], and mallards [Arias platyrhynchos (L.)] were collected from the Coeur d'Alene River Basin and two reference areas in Idaho to estimate exposure to lead from mining activities and relate that exposure to the ingestion of contaminated sediments. The average acid‐insoluble ash content of the feces, a measure of sediment ingestion, was 18% for Canada geese and tundra swans, and 12% for ducks. The 18% value corresponded to an estimated 9% sediment ingestion rate (dry weight). The 90th percentile for acid‐insoluble ash in feces of tundra swans corresponded to an estimated 22% sediment in the diet. The average lead concentration (dry weight) of tundra swan feces from all Coeur d'Alene River Basin wetlands sampled was 880 mg/kg, compared to 2.1 mg kg−1 from reference areas. The 90th percentile of lead in tundra swan feces from the Coeur d'Alene River Basin sites was 2700 mg kg−1. Fecal lead concentrations of tundra swans were correlated (Spearman's rho = 0.74, P < 0.05) with the acid‐insoluble ash content of the feces. The very low lead concentrations in feces having low acid‐insoluble ash contents established that the sediment was the primary source of the lead ingested by waterfowl. Sediment lead concentrations at 11 wetland sites were closely correlated (r = 0.91, P < 0.05) with average fecal lead concentrations for all waterfowl, corrected for the average percent acid‐insoluble ash in the feces.

Lead exposure and poisoning of songbirds using the Coeur d'Alene River Basin, Idaho, USA

“…Blood Pb concentrations were lower in osprey (Pandion haliaetus), with a mean of 0.20 mg/kg, wet weight (Henny et al 1991), and in terrestrial raptors in general (Henny et al 1994). Geese and tundra swans ingest an average of about 9% sediment in their diet (Beyer et al 1998), much more than osprey would be expected to ingest. Average blood Pb concentrations detected in songbirds from the most contaminated sites in this study were about 2 mg/kg dw, which is equivalent to about 0.4 mg/kg wet weight (Table 2).…”

“…Consequently, soils within the floodplain have been contaminated with heavy metals (Stratus 2000). The contamination has caused widespread poisoning of waterfowl (Audet 1997;Beyer et al 1998;USEPA 2001USEPA , 2002.…”

Lesser White-fronted (Anser erythropus) and Greater White-fronted (A. albifrons) Geese wintering in Greek wetlands are not threatened by Pb through shot ingestion

“…An additional important source of Pb for waterfowl is the incidental ingestion of Pb-contaminated soil and sediment while feeding (Beyer et al, 1997(Beyer et al, , 1999(Beyer et al, , 2000Heinz et al, 1999;Martinez-Haro et al, 2010. Especially in cases of heavily contaminated sediments such as in the Coeur d'Alene River Basin (Beyer et al, 1998a(Beyer et al, , 2000(Beyer et al, , 2008Sileo et al, 2001) or in the Guadalquivir marshes affected by the Aznalcóllar mine accident (Martinez-Haro et al, 2013), sediment ingestion was attested as the main source of exposure of waterfowl to Pb. Pb in soils and sediments is not readily available to plants (Beyer et al, 1997) and since most waterfowl are chiefly herbivorous, dietary Pb is not an important source of Pb intake (Behan et al, 1979).…”

Determination of porphyrins and biliverdin in bile and excreta of birds by a single liquid chromatography–ultraviolet detection analysis

“…Fecal porphyrins can be interesting biomarkers of exposure to porphyrinogenic compounds in wild animals, because their sampling is completely non-invasive and permits the easy collection of a large sample size without disturbances to protected species [2,5]. Moreover, the exposure to porphyrinogenic contaminants such as halogenated hydrocarbons and heavy metals can be also monitored in feces [6,7], which in some cases permits linkage of cause and effect within the same non-invasive sample.…”