Native Fish

The Service is responsible for the conservation and management of all native Tasmanian freshwater fish and invertebrates. This includes not only native fish such as galaxias species, whitebait and blackfish, but all freshwater invertebrates such as insects, shrimps and crayfish.

Diversity

There are 25 species of native freshwater fish, 12 of which are endemic, being found only in Tasmania. Fifteen species are in the family Galaxiidae, two are eels (family Anguillidae) and the other six species are each in a different family.

Native Fish Species List

Endemic Species

Endemic species, those found only in Tasmania, are denoted by a * in the species list. Several of these endemic species of galaxiids are confined to highland lakes, namely the golden galaxias (lakes Sorell and Crescent), saddled galaxias, Arthurs paragalaxias (Woods and Arthurs lakes only) and the Great Lake paragalaxias (Great Lake, Shannon and Penstock lagoons). In addition, there are several other species that migrate between fresh and salt water at different stages of their life cycle, and are usually widespread at least in coastal streams.

Habitat and Distribution

The native species can be divided into 3 groups with regard to their habitat and breeding pattern.

• River-dwelling freshwater species spend their entire life cycle in streams and rivers. They are the blackfish, pygmy perch and Swan galaxias. Blackfish are widepread across the north of Tasmania and have been introduced into other areas including the Huon River in the south-east and the Clyde River in central Tasmania. Pygmy perch occur in northern Tasmania including the Flinders and King Islands. The Swan galaxias has a very restricted distribution in the upper reaches of some streams in the eastern tiers.
• Lake-dwelling freshwater species spend their entire life cycle in lakes and their tributaries. They include many of the Tasmanian endemic species with restricted distributions, such as the golden galaxias and paragalaxias species.
• Migratory species move between the sea and freshwater streams at different stages of their life cycles. These include the species in whitebait runs and eels.

These species are widespread around Tasmania in coastal streams. Some species (spotted and climbing galaxias) also occur in land-locked lake populations in the highlands.

Freshwater Ecosystems

Survival of all aquatic life including fish, depends on having a healthy environment. The surrounding environment interacts with the freshwater ecosystem in several vital ways.

Bankside (riparian) vegetation acts as a filter, and provides wood and leaves for nutrients and habitat. Insects that fall into the water from vegetation provide food. Shade keeps the water cool and reduces the growth of algae. Roots stabilise banks and provide shelter for fish. Plants, rocks and wood in the water provide shelter, spawning substrate and sources of food.

Conservation Management

Trout can have a negative impact on some native fish, either directly through predation or indirectly, by competing for food and habitat.

Only a few waters within Tasmania remain trout free, and the Service is committed to maintaining this status for the conservation of native species. It is a serious offence, therefore, to transfer any fish from one water body to another, even to a different section of the same stream.

A permit is required to catch any native fish species by methods other than a bush pole, except those covered by an angling licence (blackfish, eels). Threatened species may not be caught or otherwise disturbed.