FEATHER GROWTH INFLUENCES BLOOD MERCURY LEVEL OF YOUNG SONGBIRDS

摘要: Dynamics of mercury in feathers and blood free-living songbirds is poorly understood. Nestling eastern bluebirds (Sialia sialis) living along the mercury-contaminated South River (Virginia, USA) had levels an order magnitude lower than their parents (nestling: 0.09 +/- 0.06 mg/kg [mean standard deviation], n = 156; adult: 1.21 0.57 mg/kg, 86). To test whether this low was result sequestration rapidly growing feathers, we repeatedly sampled juveniles throughout period feather growth molt. Mean concentrations increased to 0.52 0.36 (n 44) after completion growth. Some individuals reached adult within three months leaving nest, but dropped 0.20 11) once autumn molt begun. Most studies contamination juvenile birds have focused on recently hatched young with thousands feathers. However, highest risk for intoxication may be during vulnerable fledging, when no longer serve as a buffer against dietary mercury. We found that nestling were not indicative extent because large portion ingested ended up The present study demonstrates unequivocally level influenced strongly by