RV TRAVEL
To be considered for listing as a World Heritage site , a region or property must meet at least one of four criteria of ‘ universal value ’. Shark Bay , sprawling over 23,000 square kilometres , with both land and marine features of great significance , meets all four criteria .
The bay fans out around the end of Peron Peninsula , which is sandwiched between Disappointment Reach and Freycinet Reach . Along the west coast lies another peninsula , and immediately north is Dirk Hartog Island .
Given how much there is to explore , it is helpful to allow plenty of time at Shark Bay .
HAMELIN POOL
Hamelin Pool Marine Nature Reserve makes a good first stop . Here , where tidal flows are restricted and the rate of water evaporation is high , the water salinity is twice that of seawater .
This hyper-saline ecosystem makes it difficult for marine organisms to survive . Still , a few microbes – with a lineage reaching back 1900 million years – have flourished , massing together in dense colonies of 3000 million microbes per square metre .
These are stromatolites which are about 2000 to 3000 years old , growing at a rate of about 5cm each century . Fossilised stromatolites in the Pilbara region of Western Australia are dated to 3500 million years , and the microbes that built them are the first living organisms on earth . Two thousand million years later , evolution began when two microbes merged to form a single cell with an internal organisation .
Hamelin stromatolites .
/ 67