Citizen Scientists Discover New Population of World's Rarest Fish

Thanks to a discovery by a group of citizen scientists, the world's rarest fish species has doubled in numbers.

A team of divers from IMAS and the citizen science project Reef Life Survey (RLS) have discovered a new population of what is believed to be the world’s rarest fish.

Red Handfish (Thymichthys politus) are found only off south east Tasmania and until last week only one remaining population of around 20-40 individuals had been identified.

The new site, which will not be disclosed until management options can be discussed, also contains an estimated 20-40 individuals and is a number of kilometres away from the previously known population in Frederick Henry Bay.

Each site covers just 50 metres by 20 metres—about the size of two tennis courts—as the range of the handfish is limited by the fact it walks on the seafloor instead of swimming.

The new population was identified after a member of the public reported seeing an individual handfish, with a team of seven divers spending two days searching the area.

IMAS Technical Officer Antonia Cooper spotted the first fish just as the team was about to give up.

Photo: Mark Green/CSIRO/Wikimedia Commons (CC BY 2.0)

To view the Creative Commons license for the image, click here.

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