The level of protection I would recommend is simply preventing disturbance of the nest by people or domestic animals, whatever that may entail. Protecting the nest from natural predators would be tampering with nature, which anyone who reads my answers knows I don't endorse. We shouldn't play favorites or God. Life can't happen without death, and some animals and eggs are simply destined to die so that others might live. This is all part of the balance of nature. Some animals depend heavily on turtle eggs at certain times of the year and we shouldn't deprive them of this resource. It doesn't pay to get emotionally invested in the survival of any particular animal or nest; better simply to be an impartial observer of natural interactions and work to protect nature at the level of populations, species, habitats, and ecosystems. If the nest survives, great; there's a batch of baby turtles (the vast majority of which will die very soon anyway). If not, also great; some raccoon or opossum had a nice meal and helped keep Florida from being overrun with softshell turtles. I'm an ardent supporter of minimizing anthropogenic effects on nature, and that includes "protecting" nature from itself! Nature did just fine without our help for a long, long time.