Lost Sepik fish rediscovered after 40 years

A freshwater fish found only in Papua New Guinea’s Sepik River has been rediscovered after disappearing from scientific records for more than 40 years.

The Spinach Pipefish, known scientifically as Microphis spinachioides, was last scientifically recorded in 1985.

It was rediscovered during a two-week survey in the Lower Sepik River led by Papua New Guinea researcher Jerrica Agebigo, an MPhil research student with the PNG University of Technology and the New Guinea Binatang Research Centre.

The search involved scientists working closely with local communities, including fishers, village elders, women who catch freshwater prawns and market vendors.

The breakthrough came at Imbando Village along the Main Sepik River, where local woman Helen Asu helped researchers locate the fish.

Helen regularly catches freshwater prawns using a traditional hand net known locally as Umben.

After researchers showed her photographs of pipefish, she recognised the species and agreed to look for it during her next fishing trip.

The following morning, she caught two pipefish while collecting freshwater prawns along a heavily vegetated riverbank and alerted the research team.

Three Spinach Pipefish were observed over two consecutive mornings in the same area.

Two specimens were retained for further scientific examination, while photographs were also taken.

Australian ichthyologist Dr Gerry Allen later confirmed the fish’s identity after examining the photographs and identifying key features of the species.

The rediscovery has raised hope that a population of the rare fish may still survive in parts of the Sepik River system.

Agebigo says the knowledge and support of local communities was critical to the success of the search.

“Without her knowledge, initiative, and willingness to assist, the rediscovery may not have been possible,” she said of Helen Asu.

Researchers say the discovery also highlights the importance of traditional ecological knowledge in scientific research.

However, communities along the Sepik River have raised concerns about declining native fish populations and increasing numbers of introduced species.

They identified sedimentation, logging, mining, habitat damage and the loss of riverbank vegetation as major threats.

Researchers say further surveys are needed across the Sepik-Ramu Basin to determine the fish’s distribution and estimate the size of its remaining population

They also plan to develop a method using environmental DNA from water samples to detect the species without having to catch the fish.