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Well, on this trip we didn't actually hunt for anything (the signs and route were pretty apparent and no collecting was allowed), there were technically no fossils (though stromatolites predate most other life forms and have been inhabiting the planet for some 3.7 billion years), but you can't deny it was a trip so, though only scoring one out of three, I'm posting this in the Fossil Hunting Trips section. It was quite a trip and one I've had on my bucket list for some years now. I've visited (even dived, surveyed and sampled) the living stromatolites in Lee Stocking Island in the Bahamas and wanted to pay my respects to the other (more) famous modern-day locality in Shark Bay, Western Australia. Some may not know of the larger (up to 2.5 meter) Bahamian variety of stromatolites. These exist not due to hyper-saline conditions (barring other competing life forms) but due to the crazy currents that run through the channels which shift huge amounts of oolitic sands which frequently bury these stromatolites for extended periods of time. The cyanobacterial mats are not only tolerant of this periodic smothering but actually make use of the sand grains in constructing and cementing their layered structures. Other benthic organisms like corals, macroalgae and other invertebrates can't tolerate being buried from time to time and so the stromatolites capitalize on these special circumstances that allow them to proliferate unchallenged. Here are a few quick web links for those who've not heard of the Bahamian forms: http://www.bahamas.com/vendor/stromatolites-exumas https://appliedecology.cals.ncsu.edu/absci/wp-content/uploads/18_Stromatolites-Brochure.pdf http://www.robertriding.com/pdf/riding_etal1991-bahamas.pdf http://fire.biol.wwu.edu/trent/alles/Stromatolites.pdf We had planned the drive up to Shark Bay from Perth as the final leg of our Australian anniversary trip. With some good insight provided by TFF member Dave (@sandgroper) we plotted a course for several days sightseeing along the western coast of Australia to terminate at its northern extent at Shark Bay with the primary goal of paying homage to the life form that terra-formed this planet nearly 2.3 billion years ago by reducing the percentage of atmospheric carbon dioxide (pumped out by all those volcanoes early in earth's story) and increasing the level of oxygen from its initial trace amounts--called the Great Oxygenation Event (GOE) or the Great Oxidation. At first the oxygen released due to the photosynthetic activities of the cyanobacteria apparently was quickly absorbed by huge amounts of elemental iron in the earth's surface and oceans. I've heard that the earth's oceans would have had a green tinge till all of the dissolved iron precipitated out as rusty iron oxide (the source of many of those iron ore deposits today). Once the iron was done consuming all of the oxygen being produced by the cyanobacteria, the atmospheric percentage was finally allowed to climb to today's levels (actually, even higher in the past). This oxygen was one of the factors in allowing multi-cellular life (and eventually even fossil-hunting Homo sapiens) to evolve. It is for this reason that I felt the pilgrimage was in order--a creation story combined with a sort of cautionary tale of a species that so changed the world that it could no longer survive as the dominant species. Sound vaguely familiar? Anyway, enough exposition--onto some photos from the trip. We had started that morning further down the coast at Kalbarri and had left just after breakfast to make the three hour drive north to Hamelin Pool. While there was not really a great change in latitude during those three hours of listening to podcasts while enjoying the changing scenery, the temperature difference was amazing. When we left Kalbarri it was around 16C (61F) and was probably headed to a high of around 26C (79F). We could feel the outback-like temps when we made a stop at the Billabong Roadhouse for a quick break and refuel. By the time we were in the parking lot at the Hamelin Pool Marine Reserve interpretive boardwalk the thermometer in the car was reading an incredible 40C (104F). We lathered on some SPF100 sunscreen, donned our field hats with the long cape in the back, took a long drink of cool water and ambled (slowly) toward the boardwalk. The boardwalk is well illustrated with nice signs providing some good basic information on this special ecosystem for those tourists unfamiliar with these special microbial communities. As we seemed to be visiting Australia outside of the normal tourist season, we had the entire place to ourselves (as we'd experienced in many other places we visited on this trip). The site has a well constructed boardwalk built over the shore and out to a great vantage point to see the stromatolites in all their glory. Truth be told, they are not really impressive structures (probably mostly less than half a meter and mostly a blackish or brownish in color except for those furthest from shore which are exposed to the air for the least amount of time during low tides and were more sand colored). I can understand that most tourists making this stop might not appreciate the uniqueness of this site and I can picture most families would likely stop for a quick selfie while the teenage kids barely look up from their devices to glance at the odd arrangements of mushroom-like blobs arrayed before them. I can say that for Tammy and me it was an odd surreal experience to stand at this spot that I've seen in so many online photos and realize we were actually there--not unlike the powerful feeling of standing in front of a half-buried moai on Easter Island and staring into its unseeing face. Of course, being spring in this part of Australia the flies were fierce. They took special pleasure in investigating every possible inconvenient (and irritating) spot on your head to crawl around and covered us in swarms seemingly immune to any waiving of arms (and it was just too hot to even attempt that). We happily made use of our best purchase during this vacation--an inexpensive A$6 fly net to wear over our hats. It wouldn't keep them from covering us like barnacles on a whale but it did keep them from our ears, eyes, noses and mouths and that was enough to make them tolerable. We got there (by chance) at just around dead-low tide and were able to easily see the field of stromatolites stretched out before us. At the edge of the stromatolites were a small group of Pied Cormorants (Phalacrocorax various) preening themselves and resting in the hot morning sun. I hadn't expected to see fish swimming in the hypersaline waters but some small silvery species (no idea which) seemed to be tolerating the conditions well and thriving.