Birds as Bio-Indicators of Long-Transported Lead in the Alpine Environment

Abstract

Numerous investigations on mosses and epiphytic lichens have demonstrated that there is a high level of pollution by lead in alpine regions, i.e. the ecosystems which substantially form the national parks and reserves throughout the Europe. Mosses, lichens are very suitable organisms for biological monitoring of air pollution due to their specific physiological features which easily enable to measure the heavy metal deposition. However, in order to establish the temporal and spatial scale of a potential problem, connected with lead, it is necessary to consider its total residence time in all compartments of the environment. As for an example, the accumulation of heavy metals in wildlife tissues in relation to long-range atmospheric transport has not been extensively studied. Furthermore, the studies have not been done by surveying a well orientated transect along an altitudinal gradient. This study’s aim was to find bioindicators of lead pollution using birds. It was performed in the five different habitats of the Tatra Mountains, Slovakia. Along altitudinal gradients 112 bodies of 41 species of dead birds were collected. The transects were mainly on south-eastern slopes. Lead concentration in the bones of the most applicable bioindicator — Alpine Accentor (Prunella collaris) reflected that lead was deposited in the alpine areas of the Tatra Mountains as long-range air pollutants. For granivorous and frugivorous birds which live in forest and rural areas, the high individual variation of lead in the bones probably reflected the local sources of lead polution. Lead was found at higher level in granivorous and frugivorous birds than in birds predominantly eating evertebrates. Concentrations of lead in bones were significantly lower in birds of prey and owls.