Ray of light as scientists, rangers fight to save the sawfish

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A rare sawfish has been recorded on Australia’s east coast for the first time in 29 years using Indigenous rangers’ knowledge of the land and river systems.

The Pristis pristis — freshwater sawfish — was caught and tagged in a waterway in Rinyirru (Lakefield) National Park in far north Queensland.

“You got to do everything so quick … it’s dangerous,” said Christine Musgrave, a Laura Ranger and Traditional Owner.

Laura Rangers train for proficiency catching sawfishLaura Rangers train for proficiency catching sawfish
Laura Rangers Christine Musgrave, Samantha Lowdown and Jason Lowdown practice sawfish capture on a crochet version of the animal.(Supplied: Sharks and Rays Australia)

The conservation group, Sharks and Rays Australia (SARA), teamed up with Rinyirru Land and Sea Rangers and Laura Rangers to combine their cultural knowledge with science and technology.

“[The rangers] have the local knowledge of where the animals are found,” SARA founder Dr Barbara Wueringer said.

“The collaboration between SARA and Aboriginal land and sea ranger groups has just taken everything to the next level.”

Measuring 152 centimetres long, this one was just a tiddler compared to adults which can grow up to three metres long. 

Laura Rangers and SARA tag the first rare Freshwater Sawfish in almost 30 years.Laura Rangers and SARA tag the first rare Freshwater Sawfish in almost 30 years.
Susan Marsh and Robert Ross hold a freshwater sawfish while Barbara Wueringer takes a DNA sample.(Supplied: Sharks and Rays Australia)

It was caught last year, but the group had to wait for confirmation it was a Pristis pristis.

It was found about 99 kilometres inland from Australia’s east coast, but rangers said as recently as two years ago one was sighted 160 kilometres inland, although not officially recorded. 

Threatened status needs review

Dr Wueringer trains rangers how to catch, tag and DNA sample the animal safely.  In turn, they teach her the lay of the land.

As a child, Ms Musgrave recalled seeing sawfish in the waterways in the Laura area regularly, but now they are rare.

Rare freshwater sawfish swings its saw as SARA and Laura Rangers reel it inRare freshwater sawfish swings its saw as SARA and Laura Rangers reel it in
Laura Rangers say that swift action, teamwork and precision are required to capture, tag and test a sawfish.(Supplied: Sharks and Rays Australia)

Fellow ranger Robert Ross said he had only ever seen a sawfish once, a few years ago upstream at Kalpower.

“Never caught one before; it was really exciting, and gave me a shock,” Mr Ross said.

Sawfish are among the world’s most endangered fish, and no one knows how many are left.

The Pristis pristis is listed as ‘vulnerable’, but a review is due in October 2022 and SARA and the rangers believe the species status should be changed to ‘critically endangered’.

Sawfish saws are key species identifiers.Sawfish saws are key species identifiers.
Sharks and Rays Australia teaches the rangers how to identify the different sawfish.(Supplied: Sharks and Rays Australia)

Caring for country

Laura Rangers coordinator Susan Marsh said Elders had long held concerns that the health of the river was deteriorating, but evidence was needed to prove the extent of decline.

She said the sawfish was an exemplary species.

“Their memories of the river was a lot more waterholes, a lot more fish, the river flowed for a longer period during the year,” Ms Marsh said.

Rock art has great cultural significance to tribal groups from the cape who visited that area, and images of crocodiles and sawfish are depicted on the rock walls.

Laura Ranger, Samantha Lowdown pulling in a line at Olive Vale.Laura Ranger, Samantha Lowdown pulling in a line at Olive Vale.
Samantha Lowdown uses a line to check lakes for sawfish and other animals.(Supplied: Sharks and Rays Australia)

Ms Lowdown, 18, was among the crew that caught the rare sawfish and has been with the rangers for two years.

“There’s a very holistic attitude to how they manage country and how they see country,” Ms Marsh said.

“Sawfish are in the Laura Normanby rivers, we just feel that with any water strategy, land use strategy, that they need to be taken into account.”

SARA hopes more Indigenous Land and Sea Ranger groups will join the cause to study and protect the inland river systems.

“It is important to all of us really, you got to look after it, got to look after our river, our art site, our country for the next generation to grow up and learn about this country later on,” Ms Musgrave said.

Samantha Lowdown and Christine Musgrave at Olive Vale.Samantha Lowdown and Christine Musgrave at Olive Vale.
Christine says as a child they would see sawfish frequent Olive Vale.(Supplied: Sharks and Rays Australia)

Science backs traditional knowledge

The tagged sawfish will be tracked over its life, as it moves from its freshwater habitat to the ocean at about 10 years old.

Taking DNA samples helps estimate population sizes and give evidence as to whether a species has declined in some areas.

“We know historically that freshwater sawfish used to be present on the east coast all the way down to Brisbane,” Dr Wueringer said.

“Brisbane was a pupping ground for these animals.”

Sawfish return to the same pupping grounds as adults, but once they become extinct from an area, they never return.

Olive Vale on the Laura RiverOlive Vale on the Laura River
Laura Rangers say that river systems used to flow for longer and there were more waterholes.(Supplied: Sharks and Rays Australia)

Since 1936, they have been recorded four times on the east coast in the Normanby Rivers.

“We know that genetically … the population of freshwater sawfish on the east coast is distinct from the freshwater sawfish found in the gulf of Carpentaria or on the west coast of Australia.

“That by itself means that these animals require protection.”