Lobster restocking shows potential for managing resources

It could be a scene from the science fiction film, Jurassic Park

It could be a scene from the science fiction film, Jurassic Park. In a remote building - little more than a large shed - beside the shore on the south-east corner of Ireland, complex predatory creatures are being hatched and nurtured to the stage of viability before being released to the wild. There they will slowly develop and grow to maturity over a number of years, eventually to be hunted and harvested by the universal predator - man.

The lobster hatchery of the South Wexford Lobster Co-op at Carne, is an object lesson in how scientific research and co-operative education can set about restoring sustainability to an endangered fishery resource.

The hatchery is the mainstay of a long-term restocking programme which should preserve the livelihoods of more than 100 lobster fishermen between Hook Head and Rosslare - and is also helping to replenish stocks in other coastal areas.

The technology used in the project was perfected for Irish conditions at University College Galway's Shellfish Research Laboratory in Carna, Co Galway, where the first prototype lobster hatchery in the country was constructed.

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The entire project is modelled on a scientific restocking programme implemented in Nova Scotia, Canada, where seriously depleted lobster stocks have now been replenished.

The organisational initiative came from a partnership between BIM and the Wexford Organisation for Rural Development (WORD), a plc development company with broad representation of the various voluntary, commercial and community bodies in the county.

The first step was to convince the fishermen themselves, who were being asked to put their money into the project through a general levy. An expert from the Nova Scotia project was invited and his account of the success of the programme there clinched the Wexford fishermen's support. They are now enthusiastic participants. The Carne hatchery, developed since 1994, is producing some 15,000 young lobsters this year - double last year's yield - for release into the sea.

It might be described as a sophisticated lobster incubator facility. The female or "hen" lobsters are provided by the fishermen of the co-op as they turn up in pots during the hatching period between May and the end of August.

In the "hen room" - effectively a labour ward - the females produce thousands of eggs, or larvae, as they lie quiescent in their barrels of circulating seawater. As they normally hatch at night, timer switches are used to control the light for maximum production.

The microscopic larvae are then transferred to special tanks where the water is kept at a temperature of 21C and changed regularly. Each tank contains up to 1,000 larvae and the water must be vigorously aerated to keep them in suspension and constantly moving - otherwise they would eat each other.

They are fed on a mixture of natural algae and tiny shrimps. The algae are cultivated at Carne, and the shrimps are hatched there from batches of dried shrimp eggs imported at the larval stage from the Great Salt Lakes in Utah, USA.

One gram of shrimp eggs will produce 80,000 shrimps as food for the young lobsters, but the process of reconstituting and hatching them is delicate and time-consuming.

The hatchery manager, Mr John Hickey, explains the subsequent development process of the lobster larvae. They moult three times in a 14-day cycle, eating their discarded shells each time which helps them renew the calcium they need.

By the fourth stage, they can be recognised as baby lobsters. They are nurtured for up to two months more before they are ready to be moved out to sea.

The yield of viable young lobsters from the hatchery process is many times that which the larvae experience in the wild - about 3040 per cent compared to less than 1 per cent if they were born in the sea.

The system of release, again developed after extensive experimentation, involves placing the young lobsters individually in the compartments of a plastic ice cube tray. They are covered by a layer of paper tissue - which has been found, by trial and error, to dissolve in 20 minutes after it has entered the sea.

Each tray is lowered in a lobster pot - to repel predators - from the side of a boat to the sea floor, usually in a rocky environment where the young lobsters can find a safe shelter after they emerge.

They will hibernate for the first four years of their life in the wild. As they grow they can add as much as an inch to their length every year.

One of two legislative measures in force for the conservation of stocks protects the lobsters from being harvested too young. Each fisherman carries a standard plastic measuring device, and any lobster which does not exceed the set minimum body size which it defines must be returned to the sea.

The second conservation order implements the "V notch" scheme.

When a female lobster is caught, a co-op representative puts a notch in the tail in the shape of a v. The fisherman is paid the going price for the fish, which is returned to the sea, and if it is subsequently caught it must again be returned.

The restocking project is a seven-year programme which is being financed in large measure by the fishermen themselves, who pay their co-op a 2 per cent levy on the market value of their catch.

The fishermen are now pressing the Department of the Marine to introduce a management plan and licensing system, both to protect their investment and to ensure long-term conservation of stocks.

Meanwhile, the output of the Carne hatchery is so buoyant that the South Wexford Co-op has been able to sell on some stocks to neighbouring fisheries, such as the East Waterford Lobster Co-Op.

The project is supported in various ways by BIM, WORD, FAS and Forbairt. It is a futuristic and imaginative initiative.