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Feathers of Flamingo chicks were sampled in six west Mediterranean wetlands in order to assess bird exposure to metals in their natal areas. This survey, started in 2008, is to date in progress. Here we discuss sample handling and analytical methods, and present first results of Mercury analysis. Our results suggest that Mercury is more concentrated in the feathers of birds growing in the Cagliari surrounding wetlands.

The mallard (Anas platyrhynchos L.), the most abundant waterfowl species, is an important migratory component of the Holartic fauna. In Europe, massive numbers of farm-reared mallards of unknown genetic origin are released into the wild for hunting and in urban areas for ornamental purposes. Human manipulations have caused shifts in range, influenced migration propensity, led to behavioural modifications and altered the genetics of this duck species. With the aim to contribute to knowledge on the genetic consequences of large-scale game releases of mallards in southern Europe, we analysed the relationship among 245 individuals (wild and captive-bred) from eight localities in central and northern Italian regions and four from North America, by using nine microsatellite loci. In most Italian sites, a large admixture of mallard strains were observed, whereas significant genetic differentiation levels were found between urban and wild populations and among the wild population from North America and all European populations.

Assessing trace metal pollution using feathers has long attracted the attention of ecotoxicologists as a cost-effective and non-invasive biomonitoring method. In order to interpret the concentrations in feathers considering the external contamination due to lithic residue particles, we adopted a novel geochemical approach. We analysed 58 element concentrations in feathers of wild Eurasian Greater Flamingo Phoenicopterus roseus fledglings, from 4 colonies in Western Europe (Spain, France, Sardinia, and North-eastern Italy) and one group of adults from zoo. In addition, 53 elements were assessed in soil collected close to the nesting islets. This enabled to compare a wide selection of metals among the colonies, highlighting environmental anomalies and tackling possible causes of misinterpretation of feather results. Most trace elements in feathers (Al, Ce, Co, Cs, Fe, Ga, Li, Mn, Nb, Pb, Rb, Ti, V, Zr, and REEs) were of external origin. Some elements could be constitutive (Cu, Zn) or significantly bioaccumulated (Hg, Se) in flamingos. For As, Cr, and to a lesser extent Pb, it seems that bioaccumulation potentially could be revealed by highly exposed birds, provided feathers are well cleaned. This comprehensive study provides a new dataset and confirms that Hg has been accumulated in feathers in all sites to some extent, with particular concern for the Sardinian colony, which should be studied further including Cr. The Spanish colony appears critical for As pollution and should be urgently investigated in depth. Feathers collected from North-eastern Italy were the hardest to clean, but our methods allowed biological interpretation of Cr and Pb. Our study highlights the importance of external contamination when analysing trace elements in feathers and advances methodological recommendations in order to reduce the presence of residual particles carrying elements of external origin. Geochemical data, when available, can represent a valuable tool for a correct interpretation of the analytical results. © 2015 Elsevier B.V..

The feathers of greater flamingo (Phoenicopterus roseus) fledglings collected from six colonies (Odiel, Delta Ebre, Camargue, Cagliari, Comacchio and Venezia) of the western Mediterranean Sea were used as biomonitors of metal contamination of coastal wetlands, with a particular focus on mercury. We used single and pooled samples, attempting to minimise the critical factors typical of studies on metals in feathers by: sampling birds of the same age, during the same breeding season; sampling the same type of feather; treating the feathers in the same way and at the same time; and analysing the same digested solution as a single batch and in two different laboratories applying different techniques. Flamingos from Cagliari, a site known for its mercury contamination, had maxima and median values greater than any of those from the other sites in terms of both single and composite samples. There were also high concentrations at the other sites, which in the absence of literature evidence of Hg pollution, suggests either the existence of pollution or that adults are foraging in contaminated wetlands. The flamingo population of Odiel had the lowest median and dispersion of Hg, and is possibly a baseline for the western Mediterranean greater flamingo population.