Water birds covered in oil are a common sight in the aftermath of an oil spill. In this case a volunteer holds a dead Common guillemot covered in oil from the 'Erika' oil spill. The 'Erika' broke in half in rough seas around 70km off the northwest coast of France on 12 December 1999. The 24-year old tanker lost an estimated 10,000 tons of oil into the sea which washed up onto a 400km stretch of the French coastline. Recent studies have concluded that it is more humane to euthanise the birds rather than clean them. After the 'Prestige' oil spill in Spain that killed around 250,000 birds, even the thousands that were cleaned still died.