Fish farmers insist the impact is minimal, Greek scientists now claim the pollution they produce is killing crucial marine ecosystems.
As farming of sea bass and sea bream has grown in Greece and Italy, so have environmental concerns.
"These are the people who threaten our lives": The Ferret goes to Greece to find out about the immigrants assaulted and abused by the far right.
The risk of refugees and migrants drowning in the Mediterranean is increasing, but lifesaving volunteers are being criminalised.
What does the future hold for the millions of people that have fled to Turkey from war-torn Syria?
How the story of mass migration is unfolding in southern Europe, seen through the lens of Scottish photojournalist Vikki McCraw.