The “Erika” oil spill has killed more seabirds than any before
in Europe: nearly 70 000 guillemots (Uria aalge) were found dead or alive on beaches,
and many more are thought to have been killed. This unexpectedly high number
highlighted how poor our knowledge was on spatial and temporal patterns in
seabird distribution in the Bay of Biscay. The purpose of our research
project, “ERIKA-Avion”, was to fill this gap, providing the first distribution maps
and abundance estimates of seabirds wintering in the entire shelf of the Bay
of Biscay. In particular, we analysed fine-grained distribution maps for the
wintering auks, comparing their areas of highest density with the oil drift
area, and proposing for the first time (although preliminarily) minimal
abundance estimates for these birds in this area.