Jellyfish attack kills 200,000 fish at Scottish salmon farms.
Two Scottish salmon farms have suffered severe losses following what is believed to be the worst jellyfish attack on record in Scotland. The barbed-wire jellyfish (Apolemia uvaria), also known as ‘string jellyfish,’ killed 200,000 salmon across two sites, prompting emergency harvests and raising alarms within the aquaculture sector.
The affected farms, located in Invertote and Muck, reported significant fish mortality between late October and early November 2024. Data from the Fish Health Inspectorate shows that 32,000 salmon were lost at the Invertote site, while 163,232 fish died at the Muck site. Surviving fish at both locations were harvested under emergency protocols to prevent further losses.
The jellyfish, known for their venomous tentacles, inflict burns on the skin, eyes, and gills of salmon, rendering them vulnerable to infections and diseases that often lead to death. The confined nature of open-net pens exacerbates the impact, as fish cannot escape the attacks.
A Growing Threat
The string of pearls jellyfish has already caused significant damage in Norway, where last winter they killed over 3 million salmon, contributing to the country’s highest-ever mortality rates for sea-phase salmon. In response, Norwegian regulators have issued warnings and advised farmers to cull affected stocks swiftly.
While the Scottish salmon industry assesses the damage, the attack highlights the growing challenges faced by aquaculture in a rapidly changing marine environment. Further details are expected when the affected farms release their next updates.
