Hermit crab gives rise to the popular name "hermit crab", by analogy to a hermit who lives alone. Several hermit crab species, both terrestrial and marine, have been observed forming a vacancy chain to exchange shells. When an individual crab finds a new empty shell it will leave its own shell and inspect the vacant shell for size. If the shell is found to be too large, the crab goes back to its own shell and then waits by the vacant shell for up to 8 hours. As new crabs arrive they also inspect the shell and, if it is too big,
Fiddler ray Fiddler rays are harmless and easily approached by divers. Southern fiddler rays are taken as bycatch by commercial trawlers and by recreational fishers; the flesh is of good quality and sold in small quantities. The Magpie fiddler ray (previously "Trygonorrhina melaleuca") is now considered a variant of "Trygonorrhina dumerilii". There are currently 2 recognized species in this genus: Fiddler ray Trygonorrhina, also known as the fiddler rays or banjo rays, is a genus of guitarfish, family Rhinobatidae. The two species are found along the eastern and southern coasts of Australia. They are benthic in nature, favoring shallow, sandy bays, rocky