Opening the workshop, Damien Toner of BIM, outlined the importance and potential for perch culture in Ireland. Welcoming the delegates he asked for an open and frank discussion on technical issues within the industry and increased co-operation. The opening session allowed for all attendees to outline their activities and their hopes for the workshop. The workshop was divided into three sessions covering broodstock Management, spawning and larval rearing. The workshop also incorporated a visit to Keywater Fisheries Ltd. which is owned by Mr. Paul Kearney and produces juvenile European perch. The site visit afforded everyone the opportunity to visit a commercial site during spawning and was very informative. A novel split pond production system was also operational and even the Irish weather co-operated!
Sharing knowledge and good practices
The final day saw discussions on areas of future common interest and allowed the opportunity to discuss further co-operation. Areas which may potentially be explored in future concentrated around broodstock management, nutrition and egg quality. For both percid species it was deemed necessary to stop the use of wild broodstock to have a starting point for a breeding program and to secure quality broodstock supply. Furthermore, “stabilising” production was underlined as a key bottleneck to economic success, which relates to standardised operation procedures as well as sharing best practices among practitioners. Cost reduction especially in RAS would be a good indicator for the success of the stabilisation of production. For improvement of larval rearing in both species, workshop participants encouraged the industrial production of live feed and especially alternative live feed species like microalgae and copepods. Participants also pointed out the lack of knowledge in nutritional requirements especially in broodstock and the initial larval start-up phase in pikeperch and a need for better understanding of the interaction between microbiota and nutrition in the larval rearing phase.
Stabilise the reproduction
In Eurasian perch, participants highlighted the recent progress in the industrial application of hormonal induction protocols, especially to improve synchronization of spawning, in order to stabilise the consistency in reproduction. New methods and routines of broodstock induction and cryo-preservation of male gametes are considered relevant fields of future research and development to enable “stabilised” production. A common notion from more experienced industrial producers was to have a greater understanding of the reasons for production being successful or not in reproduction, with suggestions to keep a minute track record of broodstock handling and larval rearing. Furthermore, it was realised that the role of different light regimes in broodstock maintenance and larval rearing is poorly understood and deemed of high relevance for the industry. Good out-of-season reproduction success in July-October is considered a main goal and key to success for every hatchery. The focus amongst Irish producers is also the further development of a profitable Irish organic aquaculture sector.
Ultimately, producers reflected on the current dependency of producers on the market size of currently developed (niche) markets, namely in Switzerland. Even though the current Swiss market situation creates interesting incentives to start up and/or expand production for both species, it is anticipated that access to further markets and diversified product categories need to be developed.
Given the success of the event, the EPFC hope to host additional targeted workshops in the future.