Hermit crab wood and stone are used by some species). The tip of the hermit crab's abdomen is adapted to clasp strongly onto the columella of the snail shell. Most hermit crabs are nocturnal. Hermit crabs can be divided into two groups: As hermit crabs grow, they require larger shells. Since suitable intact gastropod shells are sometimes a limited resource, vigorous competition often occurs among hermit crabs for shells. The availability of empty shells at any given place depends on the relative abundance of gastropods and hermit crabs, matched for size. An equally important issue is the population of organisms that prey
Saw-billed hermit Saw-billed hermit The saw-billed hermit ("Ramphodon naevius") is a hummingbird from southeastern Brazil, the only member of the genus Ramphodon. It is around 14–16 cm long and is one of the heaviest of the hermits; its straight bill has a hooked tip. It lives in humid forests, where it aggressively defends feeding routes ("trap-lines") from individuals of its own species as well as other hummingbirds. It is currently considered near-threatened, since it has a restricted range in threatened Atlantic forests. The saw-billed hermit is placed in the hermit subfamily Phaethornithinae, but among these birds, it is the species most similar