All posts tagged: Cyanobacteria

Stromatolites Cyanobacteria Hamelin Pool Shark Bay Western Australia

The stromatolites of Hamelin Pool

It’s not a very long drive from the Overlander roadhouse to the old telegraph station of Hamelin Pool, but the dry shrub-like vegetation makes it a rather monotonous one. The barren landscape is an indication of the hot, dry and windy weather in this remote part of Western Australia, a place where summer temperatures average between 35 and 37 degrees Celsius. Those high temperatures create a very high evaporation rate that turns the shallow waters of Hamelin Pool extremely saline – twice as much as regular seawater to be precise. Under normal conditions this hyper-saline water would be diluted by the flow of fresh or low salinity waters, but in Hamelin Pool this is restricted by very low rainfall and a limited tidal flow. So what? Is salt water a good reason to stop in such a desolate corner of the world? Well, in Hamelin Pool it is as this environment is rather unique and one of the reasons why Hamelin Pool – and the whole of Shark Bay – is listed as World Heritage. …

Shark Bay Western Australia

Gutharraguda – Colours of Shark Bay

In my previous posts I have written about some of our inspiring encounters with the magnificent wildlife of Shark Bay. The Malgana people used to call this land ‘Two Bays’ or Gutharraguda – referring to the shallow waters of Hamelin Pool between Peron Peninsula and the mainland in the North and Henri Freycinet Harbour between Peron Peninsula and Dirk Hartog Island in the South. The old map of French navigator Henri Freycinet shows this piece of remarkable Australian shoreline best. Shark Bay is a unique area with vast beds of seagrass, forming massive meadows in the shallow and warm waters. Seagrasses provide both food and shelter for the stunning array of marine life, but also bind sediments moved in through tides and currants. Accumulated sediments have formed the numerous banks, sills and channels that have turned some of the bay’s waters hyper saline – the area around Hamelin Pool is twice as salty as the open ocean! Although hostile to many animals, the extreme salinity of Hamelin Pool forms the perfect habitat for Stromatolites – single celled …

Picanniny Creek Purnululu National Park Bungle Bungles Western Australia

Purnululu Dreaming – Return Downunder

The Kija people of the East Kimberly Region in Western Australia are the traditional owners of the mighty Purnululu or Bungle Bungle range. They are the testimony of human presence in this area for at least 20,000 years, following a strong tradition in which ancestral beings, ceremonies and rituals constitute Ngarrangkarni, a complex term popularly known as the Dreaming or Law. The same Ngarrangkarni explains the creation of Purnululu’s sandstone structures, gorges and waterfalls through narrative instead of definition, leaving to our imagination the formation of the landscape by creatures as the rainbow serpent, frogs, crocodiles and fish. According to our Western point of view the sandstone beehive towers of the Purnululu Range were created by twenty million years of weathering by wind, rain and flowing water instead of spiritual creatures. The dark bands that wind horizontally around these structures are formed by cyanobacteria, single-cell photosynthetic organisms that belong to the oldest life-forms on earth. As the dark bands contrast with the lighter sandstone, the myriad of dome-shaped towers form one of the most extraordinary and unique landscapes of this continent. The evocative power of the Australian wilderness is …