2.04.P-Tu081 A complementary approach based on contaminant analysis, biomarker responses and behavioural performances to investigate the toxicological status of Parus major from Veneto region

Pesticides and other classes of anthropogenic contaminants can cause reversible alterations or permanent damage to avian species. Great tit (Parus majoj) is an important model species for environmental studies. Its aptitude for nesting in artificial boxes and territoriality can provide precise toxicological information on a given territory. In the last six years, several nest boxes for great tit were installed in different areas of Veneto region, characterised by different anthropogenic impacts. This study aimed to investigate the effects of environmental contaminants on great tit populations by a non-lethal approach integrating chemical analysis, biochemical/cellular responses, breeding and behavioural traits. In 2021 and 2022, biological materials such as blood, feathers, excreta and unhatched or abandoned eggs were collected from nestlings living in nest boxes installed in different areas of Veneto region. The study areas, subjected to different anthropogenic pressures, were wooded, agricultural and urban environments. Per- and polyfluoroalkyl substances (PFAS) and heavy metal levels were determined on eggs and feathers, respectively and porphyrin concentrations were evaluated on excreta. A set of non-lethal biomarkers capable of providing different toxicological responses was performed on blood. Behavioural traits such as reactivity performances and fitness were also assessed. PFOS was the most abundant compound, and the long-chain perfluorinated carboxylic acids levels were agricultural