Any early grey nomad arrivals in the WA town of Coral Bay would have had a bit of a shock in recent weeks if they’d headed down to one of the local beaches.
Last month, a massive fish-kill event left an estimated 16,000 dead fish along affected beaches on the Ningaloo Coast, including Turquoise Bay, Bill’s Bay and Yardie Creek.
It sparked an epic effort to clean up the beaches before peak tourist season, with piles of fish skeletons scattered around.
The Department of Primary Industries and Regional Development (DPIRD) quickly warned people not the enter into or fish from the putrid water, which contained high levels of bacteria.
The ABC reports that Bill’s Bay – Coral Bay’s most popular swimming beach – was the most severely impacted.
According to the analysis of water samples from Bill’s Bay, there were no harmful algae present but ammonia, nitrates and phosphates were detected, probably the result of decaying coral spawn and fish.
Marion Massam, from DPIRD, told the ABC that the department believed the mass fish-kill event was caused by coral spawning.
“Coral spawn itself can use up oxygen in the water and when it breaks down, more oxygen is used up as part of the breakdown process,” Ms Massam said. “That reduces oxygen in the water for the fish. They can end up dying as a result.”
DPIRD said another factor which could have contributed was local marine heatwave conditions that occurred along the Ningaloo coastline in late March.
Late last week, DPIRD removed the fish-kill alert from beaches but reminded visitors to exercise caution in the area and not to enter or fish from any water that appears smelly and putrid, as it could contain high levels of bacteria.
