Citizen scientists monitor dolphins and water for algal bloom and bird flu signs in Victor Harbor

As a boat full of tourists sets off to see dolphins in Victor Harbor early on Saturday morning, they are joined on board by a group of citizen scientists.

They head out regularly, collecting samples, data and observations that have proven to be invaluable for research into South Australia's harmful algal bloom.

Now, while continuing to monitor the water, they are also watching the wildlife for signs of bird flu, after the first Australian case in a dolphin identified locally at Goolwa Beach, which was followed by a new suspected case in a sea lion at Victor Harbor.

High alert for 'beloved' dolphins

Nedra Haines has been monitoring her beloved dolphins for 14 years, as part of the Victor Harbor Dolphin Watch Group.

She has helped to compile their catalogue of 140 bottlenose dolphins and 50 common dolphins, identifying them through the shape and markings of their dorsal fins.

Information collected on each dolphin and their environment is fed into the state government's biological database of South Australia.

The dolphin watchers were, without realising it at the time, some of the first to see the very early signs of the algal bloom before it blew up spectacularly on local beaches.

Ms Haines said that while the days of the bloom had been depressing, she had watched over the dolphins, diligently recording any signs of irritation to their thick, rubbery skins.

Now she is watching to see if they show any signs of the viral infection.

Today on the boat, there is no behaviour to suggest the dolphins are anything but healthy.

Those sighted display playful antics including tail slapping, a lot of curiosity and even some carrying of seaweed, which apparently can be used to attract a mate.

Building knowledge

Also on board is Samantha Sea from the group Phytoplankton of South Australia, which formed as a response to the lack of data available to the public during the early days of the algal bloom.

She holds a degree in physics, but when the algal bloom appeared, she started attending community-led meetings, asking what could be done to help.

Since then she has pored over hundreds of samples, learning how to identify algae and other phytoplankton.

The information from Ms Sea and the network of volunteers now established across the state is being sent for use by researchers and government.

The group was recently awarded the title of South Australian Citizen Science Champions for 2026.

Even though they now tend to record low levels of the Karenia algal species, which formed the harmful algal bloom, constant monitoring is still important.

"We don't understand the ocean. Not well," she said, noting that before the bloom there was no baseline for normal levels of algae.

Now her samples are helping to build a picture of the recovering marine environment, used by the state government and Shauna Murray, the University of Technology Sydney researcher whose team identified the presence of the toxin-producing Karenia cristata within the bloom.

Buckets of help

Both a scientist in her own field and a citizen scientist with the marine environment, Niko Streiber's water samples from southern Adelaide helped Professor Murray identify the toxic species.

She had studied biology alongside her in the 1990s, and when the bloom entered Gulf St Vincent, her friend, knowing she lived near the beach, reached out to see if she could get samples of the water for her.

Dr Streiber started collecting water samples in nine-litre buckets from three different sites. Taking them home, she filtered them in her kitchen, filled tubes with the water and posted them off to Professor Murray's laboratory.

While she is not currently sampling off the Adelaide coastline, she remains ready to start again when needed, aware that the bloom could recur given the right conditions.

"We can't predict it for certain because Karenia cristata is able to survive on the bottom of the ocean; it forms little cysts, and they can spring back to life," Dr Streiber said.

"That's why the ongoing monitoring is so important."