Deadly virus stalks South Africa's sardines

Deadly sardine die-offs have been washing up on South Africa's southern coast, sparking fears of a new virus similar to one that devastated stocks in Australia and New Zealand in the 1990s. Hundreds of thousands of dead sardines and pilchards have been found on beaches in Gqeberha, coinciding with a similar event along the Western Cape coast.

Marine scientists believe the virulent pilchard herpesvirus (PHV) may be to blame, first confirmed in South African waters in July. While the virus has not been definitively linked to the deaths, low sardine numbers, oxygen-depleted waters, and harmful algal blooms may make fish more vulnerable to infection. The outbreak has already impacted the nuclear power plant at Koeberg, which had to reduce output due to clogged cooling-water intake.

Conservationists warn that the loss of sardines, a crucial species in the marine food chain, could have far-reaching consequences for dolphins, seals, seabirds, and the endangered African penguin. Fishing communities are also concerned about the future of their industry. An intergovernmental task team is coordinating efforts to investigate the virus and assess the impact on sardine stocks, with further management measures potentially warranted.