Tasmania - Threatened Species Day fact sheet
Environment Australia, 2002
Lend a hand for the walking fish!
The Spotted Hand Fish
Illustration: Barbara Cameron-Smith
The endangered Spotted Handfish is a small, unusual fish that is slow-moving and prefers to 'walk' on its pectoral and pelvic fins rather than swim. The pectoral or side fins are leg-like and resemble a human hand – hence their common name. Their body is white or cream and is covered in numerous small, closely set orange, brown or blackish spots.
The Spotted Handfish is a bottom dwelling fish that lives in coarse to fine silt and sand at depths of 2–30 metres. They spawn from September to October and lay an interconnected egg mass of 80–250 eggs on objects attached to the sea bottom. The female remains with the egg mass for 7–8 weeks until hatching. Their diet includes small crustacea and worms and they are often found in shallow, shell-filled depressions near low relief rocks projecting from the sand.
Common throughout the lower Derwent estuary and adjoining bays prior to the mid 1980s, the Spotted Handfish has suffered a serious decline in distribution and abundance. Only a handful of populations are now found around the mouth of the Derwent estuary.
Handfish lack a larval stage and hatch as fully formed juveniles (6–7mm in length) which move straight to the sea floor and appear to remain in the vicinity of spawning throughout their lives. This has two important consequences. First, colonies may be relatively isolated (ie mixing between them is restricted) and a reduction in spawning success may seriously impact on a colony. Second, the ability for Handfish to recolonise areas from which they have been displaced is likely to be low.
The cause of the decline of the Spotted Handfish is yet to be accurately determined. Suggested threats include:
- predation on egg masses, or on the food supply of the Handfish by the northern Pacific Seastar Asterias amurensis, an exotic pest;
- loss of the natural sandy habitat through increased siltation caused by land clearing; and
- heavy metal contamination of sediments and urban effluent.
Spotted Handfish are protected under Tasmanian law and the Commonwealth's Environment Protection and Biodiversity Conservation Act 1999. Over the last five years, the Commonwealth Government, through the Natural Heritage Trust, has contributed over $390 000 to help ensure the survival of the Handfish. These projects, which have included researching and monitoring existing populations; public education and awareness raising; and identifying threats, have been undertaken in conjunction with the Tasmanian Department of Primary Industries, Water and the Environment and the CSIRO.
You can help protect Tasmanian threatened species, including the Spotted Handfish by:
- protecting habitat for all our native animals;
- supporting local efforts to conserve threatened species in your area by joining a local conservation organisation, 'friends', Bushcare or Coastcare group, or by volunteering for Conservation Volunteers Australia; and
- participating in special events such as information nights, tree planting days, weed eradication programs, and seastar eradication events.
For more information on helping threatened species in Tasmania, contact the Threatened Species Network Coordinator:
Telephone: (03) 6234 3552
You can also find out more information about Australia's threatened species by calling the Department of the Environment and Heritage's Community Information Unit on free call 1800 803 772 or by visiting the Department of the Environment and Heritage threatened species web site at www.environment.gov.au/biodiversity/threatened
The Border Heath is a critically endangered shrub that is found only in Tasmania and is restricted to an area less than 11 square kilometres. There are currently about 72 000 individual plants; however, it is estimated that over three generations (or 45 years) the population will decline by 84 per cent.
The root rot fungus, Phytophthora cinnamomi, has severely impacted on border heath populations. Only 1 per cent of one sub-population remains fungus free. Fire management and disease mitigation have an extremely important role to play in controlling the spread of the fungus. Other measures that are being undertaken include border protection, scientific research and habitat protection.