Crocodile bulks of swallowed prey flesh and bone. Many large crocodilians swallow stones (called gastroliths or stomach stones), which may act as ballast to balance their bodies or assist in crushing food, similar to grit ingested by birds. Herodotus claimed that Nile crocodiles had a symbiotic relationship with certain birds, such as the Egyptian plover, which enter the crocodile's mouth and pick leeches feeding on the crocodile's blood; with no evidence of this interaction actually occurring in any crocodile species, it is most likely mythical or allegorical fiction. Since they feed by grabbing and holding onto their prey, they have evolved
Kentish plover unsustainable harvesting and urbanisation can destroy nesting sites. Plover populations can also be affected by rural human activity, for example fishermen walking through protected plover breeding sites, bringing large numbers of dogs with them- a known predator of plover eggs. Natural predators are also a problem, as many of these predators appear to thrive unnaturally well in the presence of plover breeding grounds, such as the brown-necked raven (Corvus ruficollis) in Maio, Cape Verde, the White-tailed Mongoose (Ichneumia albicauda) in Saudi Arabia, and the Grey Monitors (Varanus griseus) in Al Wathba Wetland Reserve. It is thought that the high amount