Nine new species of threatened handfish

STEPPING OUT: The endangered Spotted Handfish s found on sandy sediments at the bottom of Tasmania's Derwent estuary and adjoinging bays Picture: CSIRO

June 2010: The discovery of nine new species of the bizarre but beautiful handfish has nearly trebled the number of known species. However, there are worries that the fish, which ‘walk' Australia's ocean floor, are disappearing almost as quickly as they are found.

The new species are described in a review of the handfish family by Hobart-based fish taxonomists from the CSIRO Wealth from Oceans Flagship, Daniel Gledhill and Peter Last.

Supported by funding from the Department of the Environment, Water, Heritage and the Arts, the review of the handfish brings the family to 14 known species - six found only in Tasmania and one known from only one specimen possibly collected in Tasmania by early European explorers, yet not recorded since. It also deepens concerns about declining populations of some handfish.

Fifty million years ago they walked the world's oceans

‘Handfish are small, often strikingly patterned or colourful, sedentary fish that tend to ‘walk' on the seabed on hand-like fins, rather than swim. Fifty million years ago, they ‘walked' the world's oceans, but now they exist only off eastern and southern Australia,' said Mr Gledhill.

VULNERABLE: The Red Handfish is under pressure from habitat degradation and collection. Picture: CSIRO

Dr Peter Last warned: ‘There is evidence of shallow-water species disappearing quickly, from being common in certain areas a few decades ago, to apparently being locally extinct in some areas. They are of great importance to understanding the origins of Australian marine life, the role of Australia as a refuge during previous periods of change, and the effects on living species of habitat alteration and rapid climate change.'

He added that handfish were extremely vulnerable to environmental change - such as introduced species, pollution, siltation, fishing, sea-temperature rise and coastal development - due to their scarcity, patchy distribution, life history strategy, low breeding rates and poor dispersal ability.

Still 95 per cent of the ocean to explore

RARE:The Pink Handfish is featured in a new hotographic exhibition Picture: Karen Gowlett-Holmes

‘It's not just two or three handfish species of concern,' said Dr Last. ‘Our work has described nine new species, each with its own environmental niches and needs, and several of these appear to have very restricted distributions, and/or occur in very low abundance.'

Mr Gledhill said the handfish had proven difficult to classify due to their rarity and a lack of specimens. One of the newly named species, the Pink Handfish, is known from only four specimens and was last recorded off the Tasman Peninsula in 1999. It is now featuring in a photographic exhibition of Australia's marine biodiversity being held in Canberra to coincide with United Nations' International Year of Biodiversity.

Professor Nic Bax of CSIRO and the University of Tasmania, director of the Marine Biodiversity Hub, which mounted the exhibition, says it offers a wonderful opportunity to acquaint people with the beauty and challenges presented by Australia's vast ocean realm. ‘More than half of Australia's territory is ocean, and some 95 per cent of this world is yet to be explored,' he said.