sea turtle eggs are literally encased in a shell, but that doesn't mean that nothing can get in or out. sea turtle embryos can actually drown in their eggs because the embryo breathes through the shell, and a study published in the journal of marine sciences found that more oxygen means more healthy baby turtles which is why turtles go outside of the water to lay their eggs. only for the babies to then just go straight back into the water once they hatch. unfortunately, water can sometimes make its way into their nests, and climate change isn't doing them any favors there. rising sea levels cause more frequent flooding in turtle nests and this flooding raises the possibility of the eggs drowning. now in many cases, it takes a long time for this to be fatal one 2015 study found that if eggs were underwater for one to three hours more than 90 of the eggs survived after six hours. viable eggs only decreased by 30 percent so these little eggs are pretty sturdy, but understanding how sea turtle nests develop and hatch can help us find ways to protect them better.