CAPE TOWN, Aug. 30 (Xinhua) -- South African authorities are investigating new reports of sardine deaths along the coast, the Department of Forestry, Fisheries and the Environment (DFFE) said on Sunday.
The reports followed a statement issued on Aug. 23, in which the department said no new mass-mortality incidents had been reported since Aug. 16, suggesting that the acute phase of the event appeared to be easing.
According to a statement issued by the DFFE on Sunday, isolated sightings have since been reported at Bakoven and off Tsitsikamma, while widespread reports emerged on Aug. 27 of sardines washing ashore around Gqeberha, formerly known as Port Elizabeth, as well as floating offshore and inside the harbor.
Sardine strandings have also been reported along the Namibian coast, and Namibian authorities have agreed to provide samples for testing for pilchard herpesvirus (PHV), the department said.
The DFFE previously said testing had detected PHV in all dead sardines examined to date and that the evidence increasingly pointed to the virus as the leading explanation for the sardine deaths.
"PHV remains the leading explanation for the Western Cape mortality event. A link with the Gqeberha event is considered likely, but requires confirmation, and other causes and environmental contributions will also be investigated," it said in the statement.
The department said samples were being collected for further testing, while observers would document the distribution of affected fish and attempt systematic counts at sea.
At the Koeberg nuclear power station, about 27 km north of Cape Town and Africa's only nuclear plant, live and dead sardines have been reported in the cooling-water intake basin, with seals feeding on the fish, the department said.
Eskom, South Africa's state power utility, is managing the incident. The DFFE said it had not had access to the site but had obtained a sardine sample for testing.
The power station last week reduced Unit 1 output to 50 percent because of a buildup of marine material linked to the sardine mortality. Output was later restored to 70 percent before a turbine trip resulted in the unit being taken offline.
An intergovernmental task team met on Aug. 26 and assigned responsibilities under a response plan covering surveillance, testing, disposal of dead fish, public communication and assessment of the impact on the sardine stock.
The DFFE's Small Pelagic Scientific Working Group is due to meet on Sept. 4 to review the latest findings and consider their implications for fisheries management.
The assessment will inform advice on whether additional management measures are warranted, the department said, adding that the scale of the mortality remained uncertain.
"The scale of mortality remains uncertain, and the October/November hydroacoustic survey will provide essential information on the post-event sardine stock status," it said.
The department also urged the public not to collect or eat dead or dying sardines found on beaches or floating at sea, or feed them to pets, because of risks associated with decomposition. ■
