Nephrops occurs in the North Atlantic Ocean from Iceland in the north to Morocco in the south and into the Mediterranean. It lives at depths of between 10 and 500 metres (33 and 1,640 feet) wherever the seabed consists of soft substrate that it can burrow into. The animals spends most of its time in the burrow, emerging only to feed and to mate, and therefore shows a preference for soft, cohesive mud that's capable of supporting its unlined burrow without the need for constant excavation and maintenance.

Like all crabs and lobsters Nephrops belongs to a group of crustaceans known as decopods (ten-legged). It is pale orange in colour, and its elongated, pincer-like claws with their spiny ridges, which can be almost as long as the body, make it an easy species to identify. The hard external shell, or exoskeleton, provides support for the soft tissue beneath and affords some protection from predators. This exoskeleton does not grow with the body, and in common with other crustaceans Nephrops must periodically shed it to accommodate growth. The largest recorded Nephrops are around 24 cm (9.4 inches) long, including the fanned tail and the long front claws - although lengths of between 18-20 cm (7-8 inches) are more common.

Nephrops is a scavenger and will feed on just about anything edible it can find... including other Nephrops if the opportunity arises. Emergence from the burrow to feed seems to be affected by a variety of environmental factors such as light, tide, time of day, depth and water clarity. This makes it difficult to predict when most Nephrops will be out-and-about, and, because burrows provide a safe-haven from the trawlers, catches of Nephrops can vary significantly.

Around Ireland Nephrops typically exhibits an annual reproductive cycle. Mating takes place in early summer, and eggs are then spawned in late summer. Females carry the clump of fertilised green eggs around under their tails until they hatch out the following spring. Egg-bearing females, often described as being "berried", rarely leave their burrows, and generally avoid being caught in fishing trawls. Once hatched larvae go through various stages of their life-cycle in the plankton - a sort of organic soup of tiny plants and animals in the surface layer of the ocean - before settling to the sea bed some six to eight weeks later and taking up residence in their own burrows.

Because of the commercial importance of the species and a growing demand for fresh Nephrops in the marketplace there is danger that the population around Ireland could be exposed to the dangers of over fishing. Nephrops is the only shellfish species in Irish waters that is subject to externally imposed quotas, with the EU setting a Total Allowable Catch (TAC) for Nephrops landings each year in an attempt to manage the fishery. If Nephrops populations are to remain healthy around our coasts it is vital that the fishing and scientific community work closely together to ensure that stocks are fished responsibly within mutually agreed limits.