Today we dove at Astrolabe Reef, a remote coral atoll northeast of New Caledonia. So far its the best place we have explored. In our dives today weve seen everything one hopes to see: sharks, groupers, Napoleon wrasse, bright red old sea fans, and many other gorgeous animals. But the most impressive sight and one that we will remember for a long time was a school of 75 bumphead parrotfish (Bolbometopon muricatum). They are the largest of the parrotfishes, with a maximum length of 130cm and can weigh up to 50kg! The bumphead parrotfish is a vulnerable species, and a great indicator of fishing pressure: they are one of the few species to go away when people start fishing a reef. This is why we are so excited and happy today, because we know that Astrolabe is still a pristine reef full of large animals. This is the most precious jewel we have explored in the last three weeks. Click here to view all New Caledonia expedition blog posts.
Great Barrier Reef in High Resolution Bathymetry from Space
<img src='http://www.hydro-international.com/wosmedia/2382/wreck_island_bathymetry_using_eomap_satellite_techniques.jpg' width='200px' alt='Wreck Island Bathymetry using http://finance.yahoo.com/news/hotels-com-explores-great-barrier-140400448.html EOMAP satellite techniques’ style=’float:left;padding:5px’ />
While these coral reefs are the most ecologically significant, they are also the most difficult to map due to being either too remote or because of their shallow nature, which makes them navigationally dangerous. Germany-based aquatic remote-sensing company EOMAP used space-borne satellites. The 3D water depth maps have a 30m horizontal resolution over approximately 350,000 km2 of the Great Barrier Reef World Heritage Area and Torres Strait, providing detailed individual reef data and a complete picture of Earths largest coral reef ecosystem. The product will aid the big picture assessments of the Great Barrier Reef including water quality modeling, measuring responses to both man-made and natural impacts, such as sediment transportation and tropical cyclones, and helping to predict the impacts of climate change effects, such as sea level rise and increased tropical cyclone frequency. It will also help target priority areas for more detailed data collection, for example with the vast improvements this promises to ocean current modeling, scientists can model crown of thorn starfish larval trajectories to where they are next likely to inhabit the Great Barrier Reef. All of the mapped areas, no matter how small, are available for purchase by anyone via the EOMAP website. A coarser product (500m spatial resolution) is also available, free of charge, together with sample data of the high resolution products.