A nocturnal crustacean that hides under rocks or in crevices most of the day, the lobster is generally found in waters less than 50 metres in depth, but have been observed at depths greater than 500 metres. It has a hard exoskeleton, or shell and is brown to olive green and may be flecked with red, orange or black. The largest populations are found in the Gulf of Maine and, in Canada, around Nova Scotia and the southern Gulf of St. Lawrence.