Fishers, tourism operators and councils updated on the ongoing algal bloom

State Government agencies have met with commercial fishers, tourism operators and local councils today to provide an update on the Karenia mikimotoi algal bloom.

The meeting at the Pullman Hotel in Adelaide provided industry and local government updates on the current situation with the bloom, ongoing public health information and the impacts it’s having on the marine environment.

The meeting has also addressed future research priorities associated with the bloom to better understand how to mitigate future outbreaks. This comes after a meeting hosted by PIRSA with around 80 national and state-based marine scientists on the research occurring into the causes and effects of this bloom.

A cross government working group including SA Health, PIRSA, EPA, SARDI and DEW has been meeting weekly for the last several months to monitor the bloom and to begin preparations for interventions to assist recovery. Briefings for local government and local members of parliament have also been held as needed.

The State Government is preparing a recovery plan to enact as the bloom recedes to assist the environment to recover as quickly as possible. The Commonwealth Government will be kept informed of this plan and its assistance will likely be sought to fund some interventions. State Cabinet will be briefed about the bloom and the recovery plan next week.

State Government agencies are taking weekly water samples at 14 sites across West Lakes, the Port River and from the end of four jetties at Largs Bay, Grange, Glenelg and Port Noarlunga.

Preliminary water samples from West Lakes have confirmed the presence of Karenia mikimotoi, the species of algae first detected on the Fleurieu Peninsula in March.

Test results indicate that Karenia has been found in low numbers near the West Lakes inlet but has not been detected at the three other testing sites within West Lakes.

There have been multiple reports of fish deaths along the metropolitan coastline – North Haven between the river mouth and marina breakwater, Tennyson Beach, north of Grange jetty and south of Christies Beach Surf Life Saving Club – and Port Broughton after the June 24 storm.

Testing of water in the Coorong North Lagoon has confirmed the presence of Karenia between Seven Mile Basin and Long Point.

Experts believe the algae flowed through the Murray Mouth and into the lagoon during a strong cold front, including a storm on May 26 and high tide on May 27.

Satellite imagery of chlorophyll-a, which provide an indicator of algae concentrations but not necessarily concentrations of harmful algae, show increased levels across most of Gulf St Vincent.

These elevated levels have been recorded across the gulf as far south-west as Troubridge Point on Yorke Peninsula to West Lakes in the east. Other regions include Coobowie to Port Wakefield, Port Lincoln to Arno Bay on Eyre Peninsula, Hardwicke Bay to Wallaroo on Yorke Peninsula and along the Limestone coast from Meningie to Robe.

Latest statewide observations show sea surface temperatures have continued to decrease in shallow coastal and gulf waters.

However, deeper continental shelf waters, including around Kangaroo Island and southern Yorke Peninsula, continue to experience moderate to strong marine heatwave conditions of 1-2C above average.

For latest updates, visit: https://www.environment.sa.gov.au/news-hub/news/articles/2025/06/sa-harmful-algal-bloom-update

Quotes

Attributable to Susan Close

State Government agencies are working together to monitor the algal bloom and provide updates and information to the public, as well as to businesses impacted by the bloom.

Today’s update for commercial fishers, tourism operators and councils ensures those impacted by the bloom have the most up to date information available.

The algal bloom is a dynamic situation. Its movement depends on weather and water conditions, and therefore makes the effect on people and wildlife unpredictable.

Latest observations show increased levels of chlorophyll-a – an indicator of algae concentrations but not necessarily concentrations of harmful algae – between Port Adelaide and Aldinga.

High levels also have been detected along the eastern and western coastlines of Spencer Gulf, Investigator Strait near North Cape on Kangaroo Island, Troubridge Point on Yorke Peninsula and along the coastline from Victor Harbor to Robe.