New population of world's rarest fish discovered off Tasmanian coast

January 25, 2018, University of Tasmania
Credit: University of Tasmania

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.

"We were diving for approximately three and a half hours and at about the two hour mark we were all looking at each other thinking this is not looking promising," Ms Cooper said.

Credit: University of Tasmania

"My dive partner went to tell the other divers that we were going to start heading in and I was half-heartedly flicking algae around when, lo and behold, I found a red handfish.

"Finding a new population that is definitely distinct from the existing one is very exciting. It means there's potentially a bigger gene pool and also that there are potentially other populations out there that we're yet to find, so it's very exciting indeed," Ms Cooper said.

IMAS scientist Dr. Rick Stuart-Smith, who co-founded Reef Life Survey in 2007 with Professor Graham Edgar to collect data on global marine life, said eight individuals in the new group were identified.

"Finding this second population is a huge relief as it effectively doubles how many we think are left on the planet," Dr. Stuart-Smith said.

"We've already learned a lot from finding this second population because their habitat isn't identical to that of the first , so we can take some heart from knowing Red Handfish are not as critically dependent on that particular set of local conditions."

Credit: University of Tasmania

Dr. Stuart-Smith said that Tasmania is a global hotspot for this family of rare and endangered species.

The Spotted Handfish is still observed around Hobart, but it may be too late to find Ziebell's Handfish, a third species listed as endangered.

"The only thing that would have been more exciting last week would have been finding the Ziebell's and finding out that they're not extinct.

"Ziebell's Handfish hasn't been seen in over a decade, and there is a feeling that it's quite possibly extinct, or at least very close to being so," Dr. Stuart-Smith said.

Explore further: Nine new species for disappearing handfish family

Related Stories

Nine new species for disappearing handfish family

May 21, 2010

(PhysOrg.com) -- Nine new species of handfish have been described by CSIRO in research that highlights an urgent need to better understand and protect the diversity of life in Australia's oceans.

Global study reveals new hotspots of fish biodiversity

September 25, 2013

Teeming with millions of species, tropical coral reefs have been long thought to be the areas of greatest biodiversity for fishes and other marine life—and thus most deserving of resources for conservation.

Recommended for you

How quinoa plants shed excess salt and thrive in saline soils

September 21, 2018

Barely heard of a couple of years ago, quinoa today is common on European supermarket shelves. The hardy plant thrives even in saline soils. Researchers from the University of Würzburg have now determined how the plant gets ...

Basking sharks can jump as high and as fast as great whites

September 20, 2018

A collaborative team of marine biologists has discovered that basking sharks, hundreds of which are found off the shores of Ireland, Cornwall, the Isle of Man and Scotland, can jump as fast and as high out of the water as ...

Decoding the structure of an RNA-based CRISPR system

September 20, 2018

Over the past several years, CRISPR-Cas9 has moved beyond the lab bench and into the public zeitgeist. This gene-editing tool CRISPR-Cas9 holds promise for correcting defects inside individual cells and potentially healing ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.