The Lobster is Ireland ’s largest and fiercest crustacean. Individuals weighing a gargantuan 7.5 kg (17 pounds) have been caught by divers in secluded spots around the British Isles , but intensive fishing over several decades means it is now very rare to come across a Lobster weighing more than 3.5 kg (8 pounds).

Lobsters are shy, solitary creatures, who spend the large part of their day resting in their cave or rocky burrow. They are not aggressive as long as they are left alone, but will use their extremely powerful claws whenever necessary to defend themselves and their territory.

The claws of a Lobster are asymmetrical, and work much like a knife and fork. One claw is fast and sharp, with serrated edges, and this is used for grabbing and holding onto prey. The other claw is blunt and very powerful and this is used for crushing the shell or bones of the prey. The prey is then torn apart using both claws and fed to the mouthparts. The claws of a Lobster can be either way round, so a Lobster can be either left or right “handed”.

Lobsters, like all crustaceans, moult (shed their shell) to grow. When a Lobster is ready to moult, it jack-knifes its shell* between the back and tail, and squeezes out the gap. It leaves behind the shell of the body, legs and antennae, as well as its gills and the coverings of its eyes. The newly moulted Lobster is protected only by a new, very soft, jelly-like shell and must hide amongst weed or in its cave as at this stage is very vulnerable to attack from other Lobsters, Crabs or even fish such as Wrasse. Over the next several hours the new shell begins to absorb water and expands and hardens. During this time the Lobster grows by around 15%. After 2 or 3 days the Lobster has hardened enough to venture from its cave, and it nips out to bury its old shell in the sea-bed. It goes back into hiding again for a further 4 or 5 days, by which time the Lobster has fully hardened. It then returns to dig up the old shell and eat it! It does this to help replace minerals lost during the moult such as Calcium. The Lobster will eat all the old shell except the claws.

Each moult takes longer than the previous one, and an adult Lobster will only moult once every two or three years.

Environmental factors such as depth, habitat, food etc. greatly effect a Lobsters growth, and it is quite possible to have two Lobsters the same size who are many years apart in age. Their diet and habitat also affect their colouration, and Lobsters can range from nearly white to almost black in colour, though always with a blue tint.

*what is commonly referred to as a “shell” is in fact an “exo-skeleton” (external skeleton).