Helen Stephenson's West Australian Pictures Pages

Stromatolites are an almost unique feature of Shark Bay. Although they look like rocks, they are living organisms. In fact, they are a compound organism like a lichen. (Lichens consist of moss and algae co-operating.) When I find out which two organisms are involved in stromatolites, I will add it to this page. (What a shame my geology notes are probably in Mother's shed in Australia, while I'm in England!) Stromatolites exist in Shark Bay because the shape of the bay has caused it to become a salt trap, and the water in the bay is salty enough to keep out the stomatolites' predators. Once, stromatolites were very common, and played an important part in the evolution of our planet, releasing oxygen into the atmosphere, but with the development of higher life forms, they couldn't compete, and have disappeared from nearly everywhere except this salty environment.

Ærchie, a West Australian I know on the Internet recently told me this about stromatolites: A colony of Stromatolites has been found in Cockburn Sound, just south of Fremantle. The exact location is not being publicised although there are a large group of people who know where they are. This means there are two colonies of them.