The main food supply for critically endangered African penguins is rapidly disappearing in a mass die-off covering almost 800 miles of coastline in South Africa. Scientists confirmed the presence of pilchard herpesvirus (PHV) in the dead fish. To put these numbers in perspective, millions of dead fish clogged a cooling water intake at the Koeberg nuclear power station near Cape Town, forcing a temporary 50% power reduction.
This mass mortality event is linked to pilchard herpesvirus (PHV), the first time this virus has ever been detected in South Africa. The dead fish on the beach may only be a fraction of the total, as some could be lying on the sea floor. We won’t know the true scale of the damage until DFFE’s (Department of Forestry, Fisheries and the Environment) biomass survey in October/November 2026, yet commercial sardine fishing continues. Scientists are also investigating whether an environmental stressor, such as harmful algae, low oxygen or unusual oceanographic conditions, may have triggered or intensified the event.
The facts: what’s happening
- Mass Mortality & Disease Confirmation: On 14 August 2026, DFFE confirmed pilchard herpesvirus(PHV) genetic material in South African sardines; the first confirmed local detection.
- Coastwide Spread: Die-offs have expanded rapidly from the West Coast to Cape Town, Tsitsikamma, Algoa Bay, and Gqeberha, confirming a coastwide crisis.
- Immunologically Naïve Stock: Local sardines have never encountered PHV, meaning the population lacks built-in resistance and faces a prolonged, multi-year recovery timeline.
- Premature Commercial Fishing: Fishing continues unabated on an unquantified, potentially collapsing stock while scientists await the crucial biomass survey in October/November 2026.
Ecological, social, and economic impact
Sardines are a primary food source for Critically Endangered African Penguins (predicted to become extinct in the wild by 2035 under the current rate of decline), Cape Cormorants and Cape Gannets, as well as important line fish species such as snoek, geelbek, and hake. They’re also the bait and income that small-scale fishing communities rely on, and canned pilchards are one of South Africa’s most affordable sources of protein.
South African law allows for action
South African law already provides for a precautionary approach to managing resources: NEMA requires a risk-averse and cautious approach that takes into account the limits of current knowledge, and Section 16 of the MLRA gives the Minister explicit powers to suspend or restrict fishing when an emergency endangers, or may endanger, fish stocks or aquatic life.
We, along with our partners in South Africa, have called for a temporary pause on commercial purse-seine sardine fishing until the full impact is known thereby protecting both small-scale fishing families and the environment.