Here are some useful web resources on identifying and conserving fish and marine life…
South Africa
Southern Underwater Research Group (SURG) – if you send them a picture of the creature you can’t identify, they will help! They have also published several books on identification of marine species.
The South African Saltwater and Offshore Fish Species List has a list of species, with information about some of them.
Global
Census of Marine Life – this project occasionally makes the news with the discovery of new species.
FishBase – incredibly comprehensive database search of fish species.
World Register of Marine Species (WORMS) aims to be the most authoritative list of marine species’ names ever published.
Project GloBAL assesses the impact of fisheries’ bycatch on populations of long-lived marine species such as turtles, seabirds and ocean mammals such as dolphins.
The International Whaling Commission attempts to provide for the proper conservation of whale stocks.
The Southwest Fisheries Science Center has a list of the species they monitor, plus good information, on their Species page.