Efficient sea-lice control remains one of the most important challenges for the salmon farming industry. The use of wrasse (Labridae) as cleaner fish offers an alternative to medicines for sea-lice control, but wrasse tend to become inactive in winter. Lumpfish (Cyclopterus lumpus) continue to feed on sea-lice at low temperatures, and commercial production has escalated from thousands of fish in 2010 to well over 30 million juveniles deployed in 2016. However, production still relies on the capture of wild broodstock, which may not be sustainable. To meet global industry needs, lumpfish production needs to increase to reach c. 50 million fish annually and this can only come from aquaculture. We review current production methods and the use of lumpfish in sea cages and identify some of the main challenges and bottlenecks facing lumpfish intensification. Our gap analysis indicates that the areas in most need of research include better control of maturation for year-round production; formulation of appropriate diets; artificial selection of elite lines with desirable traits; and development of vaccines for certified, disease-free juvenile production. The welfare of farmed lumpfish also needs to be better quantified, and more information is needed on optimal densities and tank design. Finally, the risk of farmed lumpfish escaping from net pens needs to be critically assessed, and we argue that it might be beneficial to recover cleaner fish from salmon cages after the production cycle, perhaps using them as broodstock, for export to the Asian food markets or for the production of animal feeds.

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An algal consortium was isolated from an integrated steelmaking site at TATA Steel Strip Products Ltd. in Port Talbot, UK, and its bioremediation capacity tested. Excellent “bioremediation” was observed when the mixed culture was “applied” to diluted effluent from an enhanced anaerobic digestion plant at Dŵr Cymru Welsh Water at Port Talbot, UK. After 5 days of cultivation in a 600-L photobioreactor, 99% of the total nitrogen (initial level, 4500 μmol L−1) and total phosphorus (initial level, 690.4 μmol L−1) were removed from the waste stream. The consortium was deposited in the Culture Collection of Algae and Protozoa (CCAP), an international depository authority for microalgal patents, as CCAP 293/1. This material has been successfully cryopreserved using a two-step cryopreservation protocol with dimethyl sulphoxide (5% v/v) used as a cryoprotectant. On recovery of samples after 3 months storage at −196 °C, the specific bioremediation activity of the revived consortium was tested. The capacity of the revived culture to bioremediate effluent was not significantly different (p < 0.05) from a non-cryopreserved control, with 99% of total nitrogen and phosphorus remediated by day 4. Although non-axenic algal cultures have previously been cryopreserved, this is the first report of the successful cryopreservation of mixed algal consortium, with validation of its ability to bioremediate after thawing comparing non-cryopreserved cultures with a revived post-thaw algal consortium. The study also highlights the need to ensure the long-term security and the requirement to validate the functionality of conserved inocula with biotechnological/bioremediation potential.

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9Many fishes produce adhesive eggs that confer protection from currents and 1 0 predators in the wild, but that are more difficult to disinfect and aerate under 1 1 aquaculture conditions. Removing egg adhesiveness ('degumming') has proved 1 2 beneficial in the culture of many fish, and a recent gap analysis identified this as a 1 3 potential way of increasing hatching success and minimize the risk of infectious 1 4 diseases in the culture of lumpfish (Cyclopteurs lumpus), a novel species to 1 5 aquaculture. We tested the efficacy of the enzyme alcalase (0.02%, 0.2%, 2%) as a 1 6 degumming agent for lumpfish eggs, and examined its effects on hatching success, 1 7 survival, and larvae size under laboratory and commercial conditions. A five-minute 1 8 exposure to 0.2% and 2% alcalase decreased chorion thickness by 14% and 1 9 resulted in 61-75% degumming rates, without any negative effects on hatching rate, 2 0 3