A study on the concentration of heavy metals in Little Egrets from Izaro island has been published this year in the prestigious scientific journal Ecotoxicology

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The colonial ardeid Little Egret (Egretta garzetta), which is protected under the European Birds Directive (2009/147/EC), can be a reliable bioindicator of aquatic environmental pollution.

Concentrations of the heavy metals Cd, Cr, Cu, Hg, Ni, Pb and Zn in nestling feathers were assessed for three different breeding colonies of Little Egret on the Spanish coast. There were no significant differences in mean tissue residues of Cd, Ni, Pb and Zn between the colonies; however, mean concentration of Mercury (Hg) in Odiel nestlings was approximately three times lower than that of the other colonies, while Chrome (Cr) and Cupper (Cu) were significantly higher. In general, Little Egret nestlings from the three study sites had low levels of most of the measured metals, and thus the breeding populations did not appear to be at risk due to heavy metal pollution. Baseline metal concentration in feathers derived from this study and calculated and will be useful for assessment of the species with other study areas and future studies in the same colonies.

Rubio, I., Martínez-Madrid, M., Méndez-Fernández. L., Galarza, A. and Rodriguez, P. 2016. Heavy metal concentration in feathers of Little Egret (Egretta garzetta) nestlings in three coastal breeding colonies in Spain. Ecotoxicoloy 25: 30-40.