Our lobsters go through distinct growing cycle stages whilst with us, moulting their exoskeletons as they become bigger. Each area of the Hatchery is dedicated to a part of the process of producing a juvenile lobster from an egg for release back into the Firth of Forth as we hatch, rear and release.
Broodstock Lobsters in Hen Room
Our female lobsters with eggs (called berried hens) are kept in tanks until the eggs hatch. It can take many months for the black eggs to hatch in the wild, with temperature being the main factor. In a hatchery we can speed up or slow down the hatching by heating or cooling the water to manage the supply of larvae. Our hens come to us when their eggs have ripened and are ready to hatch.
Eggs close to hatching change to a brown/red colour from a darker black. The female lobster will help the larvae to hatch by pointing and “fanning” her tail which helps shake off the larvae that are ready. This is normally done at dawn and dusk over a few days until all of the eggs have hatched. We have tanks designed to receive the newly hatched larvae automatically as the water flows directly from the individual female lobster containers.
Larval Lobsters in Production Container
The hatched larvae are collected each morning and transferred to the larval tanks in the production container. In the larval tanks the tiny lobster larvae are kept in a constantly moving gentle flow of water and fed live plankton and a specially formulated diet. The movement of the water helps keeps the larvae suspended and reduces the risk of the larvae settling out on the bottom and fighting. In the wild the larvae would be floating in the top few feet of the ocean where they hatched.
As lobsters grow they shed their skin progressing through each stage until the fourth moult, where it gradually becomes more like a miniature lobster. After their third moult they are known as juveniles and are transferred to the aquahive tanks.
Juvenile lobsters in aquahive
The juvenile lobsters now begin their benthic lifestyle (living on the sea floor) and can be very aggressive towards each other so in the hatchery they are kept in individual pots. They grow rapidly and will moult every few days until they are a size suitable for release. The timing of this is dependant upon temperature and controlled by the hatchery technician, but it is most likely that juvenile lobsters will be about 12 weeks old when they are released into the sea.