Randaberg, Norway-based aquatic tech company Harbor has completed a successful share issue, oversubscribed by 30 percent, after tests of its electric stunning fence that aims to prevent pearlside jellyfish attacks showed promising results.
"Millions of fish die every year due to the pearlside jellyfish, and our technology may be the solution to this problem," Harbor COO Bernt Aage Lie said.
Harbor's fence is an electric barrier installed around seawater-immersed fish-farming cages. The company’s trials have shown that the fence’s low-voltage electric shock can trigger pearlside jellyfish to release venom, neutralizing its danger before it comes in contact with fish.
The company said it believes the jellyfish will remain harmless for several days after exposure to the electrical current, which will allow them to pass through fish-farming sites without harming salmon.
“We are the only company to have developed this technology, and interest from the industry is high and growing,” Lie said.
Jellyfish incursions have plagued Norwegian salmon farms in recent years and are responsible for significant financial losses each year. The incursions often provoke disease in farmed salmon populations, and sometimes require the culling of large numbers of fish to prevent the spread of disease.
Warming global waters have also brought jellyfish into contact with farmed salmon more often, causing higher losses.
In Scotland, where the El Niño weather pattern warmed the waters of Loch Seaforth, micro-jellyfish attacks weakened salmon that then suffered from gill disease, resulting ultimately in the death of 1 million salmon at two adjacent Mowi farms.
"Although we have not yet trialed [Harbor's] particular tool, we will watch with interest if this is found to be effective," a Mowi spokesperson told SeafoodSource. “Mowi is always looking to the future and new technology and techniques that could help mitigate the threat posed to salmon by jellyfish.”
The spokesperson added that Mowi had recently tested bubble curtains to protect salmon pens, with promising initial results.
“To combat the threat posed by jellyfish to the salmon in our care, intensive daily monitoring programs are in place at Mowi’s salmon farms, which involve species counts, water sampling, and temperature and oxygen monitoring at various depths to analyse jellyfish,” the spokesperson said.
