| Common Name: |
|---|
| grayling |
| Species Name: |
|---|
| Prototroctes maraena |
| Other Names: |
|---|
| Cucumber mullet, cucumber herring |
|
|
| Credits: |
|---|
| Photo: R. H. Kuiter |
|
|
| Conservation Status: |
|---|
| Listed as ' Vulnerable' under the Tasmanian Threatened Species Protection Act 1995. |
| Commonwealth Conservation Status: |
|---|
Listed as 'Vulnerable' under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999 |
| Fishing Status: |
|---|
| This species is totally protected and may not be taken without a permit |
| Distingushing Features: |
|---|
| The dorsal fin starts high on the back just behind the pelvic fin origin, they have an adipose fin, thin scales and no lateral line. They have a strong cucumber smell when caught and first taken from the water. |
| Colour: |
|---|
| Usually dark greenish to greyish olive along the back, with a dark mid-lateral streak separating lighter sides and a whitish belly. |
| Size: |
|---|
| Commonly 170 to 180 mm, but up to 300 mm |
| General: |
|---|
They are native to Tasmania and south east mainland Australia. It is thought that overfishing and habitat loss has caused a reduction in numbers to the point of being uncommon, although they are still quite widespread. They are closely related to the Tasmanian smelt. |
| Life Cycle: |
|---|
Spawning is believed to occur in late spring to early summer in fresh water. Larval fish are swept downstream by the river current to the sea. Juveniles return to the rivers from the sea at about 6 months of age, where they spend the rest of their lives. They have a life expectancy of up to three years, and mature during their second year. They are believed to spawn in the same portion of the river that they inhabit. |
| Habitat: |
|---|
| It is a mid-water species, that occurs most commonly in clear, gravelly streams with a moderate flow. Prefers deep, slow flowing pools. Occurs in fast moving schools and seems a shy fish that flees when disturbed |
| Diet: |
|---|
| It is an opportunistic omnivore, feeding on a mixed diet of aquatic algae and insects as well as terrestrial insects |
| Why is it Threatened?: |
|---|
| Loss of riparian and instream habitat; In-stream barriers preventing dispersal; High temperatures during low flows; River regulation with loss of dry weather flow and suppression of minor flooding; Extensive stream siltation from erosion; Stream channel damage from sand and gravel extraction; Possible predation by salmonids on the whitebait stage of their life cycle. |
| Tasmanian Distribution: |
|---|
| Occurs widely in Tasmania, although uncommon. Mainly in northern and eastern rivers, at lower elevations |
Fact Sheet for grayling
