Successful trial leads to ambitious expansion plan

by Thomas Jensen

Gints Delme, Director, Mere Shrimp Farms

Aquaculture in Latvia consists primarily of the production of common carp farmed in earthen ponds. The volume of fish produced has remained broadly stable for the last decade at about 500 tonnes. Although carp production still dominates the total output from the aquaculture sector, its relative importance has gradually decreased over the last decade, from about nine tenths of the total production to about three fourths. The reason is the gradual increase in the production of other species including rainbow trout, sturgeon, crucian carp and pike. Production of these species has led to 26% increase in the total farmed fish production in the decade to 2014 to 680 tonnes.

Developments in technology, and support from European funds have contributed to the increase in production. Recirculation systems that use very modest quantities of fresh water relying instead on a system of filters to clean and reuse the water several times are becoming more common. The ability to closely control all the parameters influencing the growing environment makes it easier and more predictable to manage a farm and these systems are therefore increasing in popularity. In Latvia, sturgeon, trout, and most recently, whiteleg shrimp (Penaeus vannamei), a warmwater shrimp, are among the species being cultivated in recirculation systems.

Excess heat from biogas unit is a cheap source of energy

The cultivation of warmwater shrimp was started by Gints Dzelme in 2013 in Riga. The facility was a pilot unit, which operated for about six months during which time the system was tested. Following this the company relocated to Dobele an hour outside Riga, where a dairy farmer offered them space. In addition to the production of milk, the farmer operates a biogas system using the biomass produced on the farm to generate electricity. The excess heat generated by the plant is used to warm the water to the temperature that is needed to grow the shrimp. A cheap source of heat was a compelling argument to move the cultivation to the dairy farm despite the cost and effort of dismantling and rebuilding the system and Mr Dzelme immediately began to consider expanding the operation. The plan is to develop the facility in three stages each of which will result in a production of about 35 tonnes of shrimp. Much of the preliminary work has been completed and now the drawings are being prepared so that building for the first stage will commence around the middle of 2016.

The shrimp is distributed very fresh and can even be delivered to the restaurants live, which is quite unique. Selling live tropical shrimp to restaurants in northern Europe is something not many can emulate.

In contrast, the pilot plant that is currently running has a production of 2 to 2.5 tonnes. This is very small, says Mr Dzelme, and it means that although we are selling the shrimp, we cannot start approaching the retail chains or food service sector as we do not yet have the volumes they need us to supply. We have been surprised by the demand for the product, which despite its high price is very popular. The company has therefore temporarily stopped all marketing activity as it has led to expectations from customers that Mere Shrimp cannot yet meet. The expansion plans include the building of a hatchery as the production of large volumes of shrimp is more economical when the post larvae are produced in-house. Currently, with a much lower level of production, the company is importing the post larvae from the United States. Once the new facility is built and production moved there the existing facility will be repurposed into a hatchery.

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Expertise in waste water treatment is used to grow shrimp

Mr Dzelme has a background in the area of waste water treatment. For more than 15 years he has been supplying aquaculture farmers and others solutions for the treatment of waste water. We are very familiar with how to design and build these systems, he says, but it took a little longer to understand about shrimp production. While finding information about these processes is relatively easy, it is far more complex to actually build these systems, learn how to control them, and decide how automated they should be. Growing shrimp is not just a question of placing the organisms into a tank. A successful commercial enterprise will have to do far more than this, otherwise it would just be a hobby.

Annual production is currently limited to some 2.5 tonnes, but plans to expand this to 35 tonnes are almost finalised.

The shrimp take five to six months to reach a size of around 25 g. While this is an acceptable weight for the market, larger sizes command higher prices. However, the costs of growing the crustaceans to a larger size needs to be weighed against the benefits. As with most aquaculture, feed is the single biggest cost in the production. At Mere Shrimp the feed is specially formulated to reduce the protein content. Mr Dzilme explains that is because the company is using bioflocks which provide a protein-rich source of feed. Bioflocks are agglomerations of microorganisms and waste matter that function both as a source of feed and as water treatment plants. The bacteria, algae and micro-fungi that constitute the flocks feed on the nitrogen, phosphorus and other elements that result from the breakdown of the waste feed and the excretions of the shrimp, thereby cleaning the water in the production tanks. The shrimp in turn feed on the bioflocks and thereby reduce their dependency on the protein content of the regular feed. We only need a protein content of 25% in the feed, says Mr Dzilme.

Freshly harvested shrimp are best consumed raw

The bioflock agglomerations are on the surface of the water. With vannamei shrimp this however is not a problem as they swim throughout the tank at the surface as well as the bottom. The tanks the shrimp are currently being raised in have a depth of 1.7 m and a volume of slightly over 40 cubic m. Three hundred to 350 kg of shrimp can be raised in tanks of this size. The depth of these tanks is greater than that of some of those used when the facility was located in Riga as shallow tanks can sometimes have problems with the levels of oxygen dissolved in the water, an issue that is solved by using deeper tanks. The water used to farm the shrimp is freshwater to which salt is added to give a concentration of 20 ppt. The recirculation system maintains a very stable environment for the shrimp; oxygen, pH, temperature, and salinity are all controlled, and other pollutants are taken care of by the filters so there are no problems with disease. Both the shrimp and the fe
ed are tested at regular intervals at independent laboratories to ensure that no unwanted substances are present. In fact, says Mr Dzelme, we are so confident of the quality that we recommend that they be consumed raw. The shrimp is distributed very fresh and can even be delivered to the restaurants live, which is quite unique. Selling live tropical shrimp to restaurants in northern Europe is something not many can emulate.

The shrimp farm the company has established has given it the experience necessary to participate in shrimp projects in other parts of Europe. Currently, the company has an interest in ventures in Germany, in Italy, England, Russia, and Ukraine, where it’s knowledge and experience about the technology behind farming shrimp is proving very valuable. In addition to farming shrimp itself Mere Shrimp Farms is also a consultant to the European shrimp cultivating industry.

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