News & Views
A handbook for hatching lobsters
By Quentin Dodd
By Quentin Dodd
As the NEPHROPS project nears the end of its 36 months, the release of a full-length video and handbook about the Nephrops norvegicus (Norway lobster) are expected early this year. The project, named “Development of new techniques in hatchery rearing, fisher enhancement and aquaculture for Nephrops” started in February 2012. The EU Framework 7 project has been a collaborative venture between SMEs (small to medium enterprises) and RTDs (research, technology and development) across Europe. Nephrops has received €2.4 million.
August of 2014 heralded a breakthrough when scientists at Swansea University in Wales, through the university’s Centre for Sustainable Aquatic Research (CSAR), achieved successful hatching and initial rearing of the lobster, also known as the Dublin Bay prawn, scampi and langoustine. The lobster is one of Europe’s higher-priced and most prized shellfish, with 59,000 tonnes caught commercially each year, with an off-the-boat sale value of close to £200 million.
The Centre has played a key role in developing a pilot scale hatchery for the species, with an overarching goal of testing the feasibility of releasing juvenile animals into the wild to assist restocking and recruitment.
In the hatchery-nursery facility, egg-bearing adult females are allowed to spawn naturally and the resulting larvae are then cultured through the first three successive stages in upwelling tanks designed to simulate the currents of the open ocean.
After roughly 25 days in the facilities, the larvae metamorphose into lobster juveniles and settle to the bottom of the tanks.
Initial research at the centre, which was carried out in association with the Orkney Lobster Hatchery in Scotland, was based on previously-established techniques for the commercial culture of the larger European lobster, Homarus gammarus.
But while the two species share a similar life cycle, langoustine larvae proved notably less robust and are more challenging to culture and there were a couple of difficulties with the feed and larvae-flotation or buoyancy system at one point.
In the wild, states the university, there is known to be very high natural mortality rate. That’s especially the case during larval stages, as discovered in previous efforts to rear langoustine larvae in captivity. At best, says the centre, just 5% of the initial larval population survived.
But after three seasons of effort, the CSAR team working on a pilot commercialization, scaling-up program was able to bring the survival rate to metamorphosis up to over 50%, with hundreds of juveniles predicted during the upcoming season.
The results under project leader Dr. Adam Powell will culminate in a full-length video and hatchery handbook, soon to be available online — www.nephrops.eu
“The project team anticipates these results will be of particular interest to the aquaculture industry, as they demonstrate the potential to successfully rear this species for release,” Powell said.
— Quentin Dodd