Imagine large pods of mighty blue whales and orcas darkening the waters off Cornwall, England, while closer to shore blue sharks and thresher sharks chase herds of harbour porpoise and dolphins.
Pure fantasy? No, in fact that extraordinary abundance of marine life off the English coast was the norm for oceans around the world not so long ago, researchers have now documented.
And then humans began to mine the seas of anything worth eating.
"The impact of fishing over the centuries is far larger than anyone thought," said Poul Holm, a professor at Trinity College in Dublin and global chair of the History of Marine Animals Population (HMAP) project which part of the 10-year Census of Marine Life.