Technological development, planning and construction of a pilot plant for the organic rearing of giant tiger prawns (Penaeus monodon)
BMWI – ZIM – KOOP KF
01.02.2010 – 31.05.2012
Organic prawns are a delicacy. A delicacy in harmony with nature and the environment.
Whilst conventional prawn farming even today often still endangers nature and mankind (clearing of ecologically important mangrove forests, pollution of water through use of antibiotics, chemical residue in the final product, taste, etc.), top-quality prawns, which are in harmony with nature and the environment, are produced in ecological aquaculture operated according to organic standards.
WAB Trading International GmbH is an enterprise which since 2007 has been running the Organic Shrimp Project (OSP) in Bangladesh, within the framework of which 3.600 smallholders are currently involved in the organic production of giant tiger prawns (Penaeus monodon) in accordance with Naturland criteria. The prawns are produced in two stages: 1. Cultivation of the so-called larvae in hatcheries and 2. Raising of the young prawns in pools until they are ready for the market.
There are various areas where there is the potential to improve production in the breeding of larvae in the hatcheries.
Reduction of transport costs and CO2 emissions: Hatcheries and pools are often far apart since the parent stock and larvae live in seawater but the young prawns in brackish water. Long transport routes lead to higher mortality of the larvae and the transport costs raise the price of the larvae significantly. In addition, CO2 emissions (transport by air and truck) endanger the climate. A sustainable solution is the production of the larvae in the same region as the breeding of the prawns. What is needed for this is an energy-efficient increase in the salinity of brackish water from the breeding grounds.
Improvement of water quality: The water quality in the hatchery is critical for successful larvae breeding. It is particularly important to prevent an accumulation of metabolites because these curb the prawns’ growth and can lead to diseases. For this reason, the water is constantly renewed. Through appropriate water treatment, water consumption can be reduced and the impact on nature reduced.
Larvae reproduction: The sustainable reproduction of P. monodon in captivity has so far been unsuccessful. The females are to date taken from wild stock. To start the spawning process, it is common practice for one of the eyestalks of the female to be surgically removed (so-called eye ablation). There is an urgent need for a species-appropriate process for controlled artificial reproduction of this type.
In order to find a solution for these issues, ttz Bremerhaven, WAB Trading International GmbH and the Gesellschaft für Marine Aquakultur (GMA) mbH are developing a pilot plant within the BIOHATCH project for a hatchery for the organic rearing of larvae of this type of prawn. In the framework of three sub-projects, the individual components of a promising technology, comprising a customised salt water supply on the basis of electrodialysis and photovoltaics (ttz), water treatment via biofiltration (WAB), as well as sustainable induction of spawning and egg maturation through light and temperature protocols (GMA), is being developed.
After the integration of these three individual components on a pilot scale in the target region (Kaliganj, Bangladesh), the ai is for the new technology to be further developed to production scale and rapidly marketed after the end of the project.