Shipud writes: The Dead Sea, that with a 33% salinity is one of the most extreme environments on earth, has been found to be more alive than previously imagined. A groups of Israeli and German scientists have discovered freshwater springs deep in the Dead Sea. The springs are about 30m deep, and lie in of large craters 30m in diameter. Preliminary analyses of samples collected in the craters suggest that the springs’ bacterial communities are very diverse—akin to what you’d find living on rocks in a regular saltwater sea (3.5% salinity). The top of the springs’ rocks are covered with green biofilms, which use both sunlight and sulfide—naturally occurring chemicals from the springs—to survive. Exclusively sulfide-eating bacteria coat the bottoms of the rocks in a white biofilm. Not only have the organisms evolved in such a harsh environment, the scientists speculate that the bacteria can somehow cope with sudden fluxes in fresh water and saltwater that naturally occur as water currents shift around the springs. Link to Original Source
I've never been canoeing before, but I imagine there must be just a few
simple heuristics you have to remember...
Yes, don't fall out, and don't hit rocks.