Shark Bay, Western Australia - (World Heritage Natural Site in Australia)

Shark Bay, Western Australia

Short Report

On the most western point of the Australian mainland, Shark Bay, with its islands and the country around it, has three special natural characteristics: the large sea-grass beds, the largest of which (4,800 km2) and richest in the world; the dugong ( 'sea cow') population; and the stromatolites (colonies of algae which hard, Domed deposits and are among the oldest forms of life on earth).  Shark Bay is also the home of five types of endangered mammals.

Wide Report

At the most westerly point of the Australian continent, Shark Bay, with the remarkable coastline and islands, has three special natural characteristics: a large seagrass carpeting adds beds, The largest of which (4,800 km2) and the most species-rich in the world; the dugong population (estimated at 11,000 ); and the stromatolites (colonies of algae which hard, Domed deposits and are among the oldest forms of life on earth).

The inland terrestrial landscape of Shark Bay is predominantly of low hills interspersed with birridas inland salt pans. Shark Bay is a large shallow embayment, approximately 13,000 km2 in area with an average depth of 9m, enclosed by a number of islands. Inflow of oceanic water through channels: Naturaliste Channel in the north and south Passage in the south. The striking feature of the bay is the steep slope in salinities. The ranges of oceanic in the northern and western part of the bay via metahaline to hypersaline. The salinity slope has three biotic zones that have a significant effect on the distribution of marine organisms in the bay. For almost 3,000 million years (i.e. 85% Of the history of the life) only microbes populated the Earth. The only macroscopic evidence of their activities is preserved in stromatolites, which are the largest variety 850 million years ago. The stromatolites encrypt evidence of the biology of the microbial communities that created them and the nature of the environments in which they are grown. They dominated the shallow seas and made extensive reef tracts are comparable with modern coral reefs.

Although microbes have not declined in importance, their activity in building organo-sedimentary structures is the more efficient market niches in reefs composed by faster growing organisms, or even occupy positions of power in the organisms themselves. Consequently stromatolites and other microbialites have declined in importance in this period, even though they remained locally important in environments such as Hamelin Pool in Shark bay, where biotic diversity is limited for one or other reason. The stromatolites and microbial mats of Hamelin Pool were the first modern, vivid examples to be recognized as comparable to those which the early seas.

Modern analogues such as arise in great diversity and wealth in Hamelin Pool significantly help in the understanding of the nature and the evolution of the Earth biosphere to the early Cambrian. The Hamelin Pool stromatolites is considered a 'classic' site for the study and classification of stromatolitic microbiolites, morphology, and the biology of different types of living can be examined by means of a series of environments.

The Shark Bay region is an area of great zoological importance, mainly due to the isolation habitats on peninsulas and islands should be isolated from the disturbance occurred elsewhere. Of the 26 species endangered Australian mammals, five are on/Bernier and Desert Islands. These are the boodie (burrowing bettong), rufous hare-wallaby hunting, banded hare-wallaby hunting, the Shark Bay mouse and the western blocked bandicoot. The Shark Bay region has a rich avifauna with more than 230 species, or 35 %, of the Australian bird species are recorded. The site is known for the marine fauna, the population of about 11,000 dugong, for example, is one of the largest ski resorts in the world. Humpback and looking use the bay as a migratory hangout. Bottlenose dolphin occurs in the bay and the green turtle and the loggerhead turtle nest on the beaches. Large numbers of sharks including bay whaler, tiger shark and hammerhead sharks are easily detected. There is also a population of rays, including the manta ray.

The recording of aboriginal occupation of Shark Bay stretches over 22,000 years BP. At that time the most space was dry country, rising sea levels flooding Shark Bay between 8000 BP and 6000 BP. A large number of indigenous center sites are found, in particular on Peron Peninsula and Dirk Hartog Island which evidence of foodstuffs of the waters and the nearby areas. Shark Bay is named for the English buccaneer William Dampier in the late 17th century. It is the site of the first recorded European landing in Western Australia, with the visit of Dirk Hartog in 1616, followed by William Dampier in 1699.

Source:whc/unesco