New photos show extent of rock lobster walkout on West Coast

Hundreds of West Coast rock lobster and other marine animals washed ashore near Elands Bay following a red tide event last week.

Photographer Steve Benjamin documented the scene early on Wednesday morning, 25 February, after receiving an alert about a rock lobster walkout linked to red tide on Elands Bay point

His images show stretches of coastline scattered with washed-up rock lobster while authorities attempted to move the dying crustaceans to deeper, oxygen-stable water.

Fish and other sea creatures affected by low-oxygen conditions

Benjamin noted how the ocean had appeared very different the night before, as he and his wife had watched the bioluminescence shimmer in the dark.

“The same [algal] bloom that lit up the ocean had revealed its darker side,” he wrote. “Massive bio-load. Oxygen stripped from the water. Nothing left for marine life to breathe.”

The marine photographer proceeded to gather a small cross-section of what had washed up to show that it wasn’t only rock lobster that had been affected.

“There were dark shy sharks, two pyjama sharks, and a heartbreaking number of rock suckers – one of my favourite fish,” he added.

“There were also smaller numbers of jackopever, mullet, juvenile galjoen, Hottentot, plenty of klipfish, sea urchins and octopus.”

Red tide leads to lobster walkout

The Department of Forestry, Fisheries and the Environment (DFFE) confirmed that red tide conditions triggered large-scale marine walkouts and mortalities in and around Elands Bay last week.

The DFFE warned the public that the washed-up rock lobster and fish were not safe for human consumption.

“The time of death of these animals cannot be confirmed, and exposure to algal toxins and bacterial contamination poses a serious health risk,” the DFFE stressed.

In spite of these warnings, Benjamin noted how some locals were collecting lobster tails from the washed-up mass.

The DFFE subsequently activated the West Coast Rock Lobster Walkout Contingency Plan, which included relocating live rock lobsters and conducting scientific assessments of affected stocks.

What causes these events?

Mass walkouts linked to red tides are driven by dense algal blooms, often dinoflagellates (phytoplankton), that build up in the shallows.

“Like land plants, plankton need sunlight to live and grow,” Dr. Lauren De Vos from Save Our Seas told The South African.

Occasionally, these dense blooms discolour the water red or brown. This is what gives them the name ‘red tides,’ while scientists call them Harmful Algal Blooms.

Algal blooms that are non-toxic can still cause death to marine animals when their numbers build up. Some block oxygen uptake by fish, some deplete all the nutrients before dying, and their decay sends oxygen levels plummeting.

“Animals like rock lobsters try to escape the deadly conditions in the shallows, and become stranded on the shore – a lobster ‘walkout’,” De Vos added.

A similar red tide event was reported along parts of the West Coast in January, when large numbers of white mussels, whelks and other shellfish washed ashore near St Helena Bay and Elands Bay.