The new torus incubator
The new lobster incubator
The first 4 stages of development from newly hatched (stage 1) to metamorphosed post larvae (stage IV) take approximately 24 to 30 days in the wild and only about 1 in 20,000 hatched larvae will make it to reproductive age. In a hatchery survival to stage VI-VII (when they can safely be released in the fishery) can be increased to about 12 in 100. The time spent in the Larval Incubator is reduced to reach stage IV in around 10 to 12 days depending on temperature and feed.
Between stage I and stage III they do not have the appearance of a lobster as they are in their pelagic (shrimp-like) form and display the typical front claws at stage IV. At this stage, they swim and can be netted-out from the earlier stages which sink down after the aeration is turned off. This is the transitional phase between a free-swimming animal and a settled juvenile lobster (stage V and later) that would naturally seek shelter on the substrate and hide. The reason we don’t release lobsters at stage IV is that they are extremely vulnerable during this time to predation.
The role of an incubator in the lobster hatchery
The larval incubator has a very important role as it keeps the lobster larvae in suspension within the water column and gives them access to food. In the wild, encounters between juvenile larvae are uncommon but in an incubator encounters are a significant factor. This is why we look very carefully at the way water moves within an incubator to minimise encounters. The stocking level in an incubator is typically between 25 and 45 lobster larvae (stage I) per litre.
One important factor in designing a hatchery is the number of incubators, regardless of size, which is required due to the requirement to only fill an incubator with that day’s larval hatch. It is recommended for a hatchery where the aim is to have continuous production through the season, that they have a minimum of 12 incubators – as this represents enough to fill one each day in a 12-day cycle. Smaller numbers of incubators mean that a proportion of hatched larvae will be wasted.
Finding the solution
The torus crustacea incubator has been designed from a background of 20 year’s experience in aquaculture technology to provide the best versatility and survival of larvae. We have redesigned the outflow screen to minimise encounters and eliminated air stones at the base of the vessels which can move around and can damage a significant number of larvae. Specifications are as follows.
Working Water volume 120 L (at mode 3) – dimensions 900 mm high 600 mm deep and 400 mm wide.
There are three modes of operating volumes:
Mode 1 capacity 1500 stage I
Mode 2 capacity 3000 stage I
Mode 3 capacity 5500 stage 1 Switching between modes – at fill – is very simple and involves minimal operator effort.
The Torus Incubator is designed to be cost and space-effective. The productive use of space in the Torus Incubator is 56% compared with 18% in more conventional, round, incubators. The units are freestanding so require no base. They are also made to make life easier for the operator as the system can be drained back into the filter system or a drain plug removed at the bottom to enable sterilisation cleaning without contamination of the system.
The Torus Incubator, when used with the air system, is suitable for the European and American lobster.
Designed with versatility for other species
With a small alteration to the incubator, the air input can be configured for water to drive a gentle circulation and larger gentler vortexes within the volume of water which makes it suitable for the following species.
European spiny lobster (Palinurus elephas)
Caribbean spiny lobster (Panulirus argus)
Norwegian lobster (Nephrops norvegicus)
