Naturally high heavy metal concentrations in feathers of the flightless KaguRhynochetos jubatus

Abstract

We assessed heavy metal concentrations in feathers of 38 Kagus Rhynochetos jubatus living on ultramafic soils in New Caledonia. Concentrations of heavy metals in down feathers were similar to concentrations in shafts of primary or secondary feathers, whereas the concentrations in vanes were much higher, indicating that concentrations in down feathers were not due to external contamination but rather to ingestion. Although there was no anthropogenic pollution in our study area, concentrations of iron (Fe), zinc (Zn), manganese (Mn), chromium (Cr), selenium (Se), strontium (Sr) and cobalt (Co) in feathers were 1.2–21 times higher in Kagu than the average in other bird species studied, the majority of those from polluted environments. Kagus may have specific adaptations that enable them to live in environments with naturally high heavy metal concentrations.