31.   A man in a tweed blazer and a white sun hat walks slowly through a patch of sea grass on the coast of northern Japan, searching.

32.   Sediment and nutrients damage sea grass beds and create algae growth, while pesticides and herbicides stop the growth of plankton and sea grass, the report said.

33.   Silt can bury reefs or sea grasses that protect juvenile fish, commercial species such as snapper or green sea turtles.