Beachgoers urged to report dead seals

PLETTENBERG BAY NEWS - Dead seal pups have started washing up on Plettenberg Bay beaches following rough sea conditions over the past few days.

This takes place every year during the Cape fur seal pupping season which starts in November.

Local beach authorities are, however, urging beachgoers to report dead seals to the Plett Stranding Network.

Experts from local conservation organisation, Wild Ocean, explained that up to 45% of Cape fur seal pups born on the Robberg Peninsula drown within the first month of their lives as a result of large ocean swells.

"Such high rates of mortality prior to weaning are not unusual in fur seal pups," the team said. "Displacement and drowning due to rough weather have been identified as the main natural factors causing high levels in Cape fur seal pup mortality at other breeding colonies along the south coast of South Africa, and have also been recorded in a number of seal species in other parts of the world."

They explained that young Cape fur seal pups cannot not swim well and are born with a black coat, not yet insulated for survival in the ocean.

"They spend the first three months of their lives in a rookery among the rocks and boulders of the Robberg Peninsula north shore, while suckling rich milk from their mothers. While waiting for their mothers to return during short foraging trips to sea, they form large crèches close to the water's edge. Here, many get swept away from their rookeries - particularly during periods of high easterly winds and swell, notoriously common in summer."

They further explained that most drown and wash up on the mainland, especially on Robberg Beach, but a few are rescued and then later returned to the colony by local tourism operators.

Adult deaths
"During previous seasons up to 600 newborn pup carcasses were recovered along Plett beaches. In contrast, only about 50 carcasses from older age classes (yearlings, sub-adults and adults) wash up each year, mostly from November to May, with a peak in January.

"Although the majority of these carcasses wash up in an advanced state of decay, there are necropsy (animal autopsy) records for a number of fresh carcasses which report on various usual and unusual causes of mortality and secondary symptoms.

"These include shark-inflicted bite wounds, stingray-inflicted spine wounds, parasitic infestations, entanglement in fishing gear and plastics and shot seals."

The team said breeding season is a highly stressful time for adult seals, especially older males, that lose body condition as they spend much energy fighting one another to establish and maintain breeding territories.

"It comes as no surprise that more than 90% of adult carcasses recovered along Plett beaches during past breeding seasons were large males. Recently weaned yearlings are also known to struggle at this time as they learn to find their own food in order to make the transition to adulthood."

Beachgoers are urged to report seals on beaches to the Plett Stranding Network on 079 463 4837. The network includes seal researchers, voluntary rescuers and local rehabilitation and carcass disposal authorities.