Where there's mud, there's wealth if you're an eider duck or an avocet. And there's more mud in the Wadden Sea (the shallow edge of the North Sea fringing Holland, Germany and Denmark) than anywhere else in Europe. Millions of birds, sea farmers and jet setters are competing for the black treasure.
The 'wealth' is the hoard of plants and tiny creatures that live within the mud, and are food for their bigger neighbours. How do worms that build snares of sand, blizzards of probing avocets, and the technology of fishermen make the rich economy work? How are tourism and pollution from the distant factories along the Rhine interfering with the balance?

(from Bristol)
(Colour)