Evidence of lead exposure in a free-ranging population of Kea (Nestor notabilis).

Kea (Nestor notabilis) are high country parrots endemic to New Zealand. The foraging behavior and inquisitive nature of Kea have led to incidences of foreign substance ingestion, including lead. Between April 2006 and November 2007, 38 Kea in Aoraki/Mount Cook National Park, New Zealand, were captured, and blood was sampled for blood lead analysis. All birds sampled had detectable blood lead with concentrations ranging from 0.028 mg/l to 3.43 mg/l (mean+/-SE, 0.428+/-0.581 mg/l). A retrospective analysis of necropsy reports and archived samples from 15 wild Kea from various South Island locations also was carried out. Seven of these birds (five from the Aoraki/Mount Cook area) died with clinical signs consistent with lead toxicosis and had liver and/or kidney lead levels reported to cause lead toxicity in other avian species. All seven of these birds also had lead inclusions (Ziehl-Neelson positive intranuclear inclusion bodies) in the renal tubular epithelial cells. These are considered diagnostic of lead toxicity in other species. This study showed that lead exposure is ubiquitous in the sampled population and may be an important contributing factor in Kea morbidity and mortality. As a result of these findings, lead abatement in areas frequented by Kea is being initiated.