It can be hard to get overviews and up-to-date information on key conservation issues. Here are the basics about some of the endangered species and places particularly close to Mark's heart, beginning with sharks (below) and the Great Bear Rainforest, rhinos and kakapo (click on the links above).

Sharks

As many as 100 million sharks are killed each year for their fins, which are used to make shark-fin soup. The main market is China and Chinese communities in Asia and elsewhere. Finning is incredibly cruel - the fins are often removed from the sharks while they are still alive - and it is threatening shark populations around the world. The counter above represents the number of sharks being killed worldwide since 1 January 2011. Find out more at The Shark Trust.