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Freshwater Fish of Victoria - Hardyheads | FN0062 |
Charles Barnham PSM
April, 1998 |  |
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Family:
Atherinidae
General characteristics:
Two separate dorsal fins, the first rather small. A silvery band along the sides. No lateral line. Marine sub-species are c confused with small mullet, but are readily distinguished by the single spine in the anal fin.)
Common Name:
Small-mouthed Hardyhead
Other Name/s:
Greyback
Scientific Name:
Atherinosoma microstoma (Gunther, 1861)
Status:
Native
Description
Slender, long body, almost flat on top. Pointed or slightly rounded snout. Large eye, high on the side of the head. Small upturned mouth, which does not quite reach the front of the eye. Translucent body, pale olive-greenish above, light green, white or silvery below. Broad silvery stripe along the sides. Yellowish fins with black spots at the fin bases. Dark line along the base of the anal fin and the lower tail.
Distribution
Widespread and abundant along the Victorian coast.
Habitat
Essentially an estuarine species, but found in coastal lagoons and lakes and associated streams, near aquatic vegetation, and in streams connected to estuaries and the sea.
Brief Biology
Can be found to 8 cm in length. Spawning occurs in Victoria from late spring through summer. Little is known of the life history. Maximum life span believed to be 1.5-2 years. Appears to be tolerant of a wide range of salinities. Primarily a carnivore, eating small crustaceans, insects and worms.
Other Notes
Important part of the diet of larger estuarine fish and water birds.
Common name:
Unspecked Hardyhead
Other Name/s:
Freshwater silverside, Fly-specked hardyhead
Scientific Name:
Craterocephalus stercusmuscarum fulvus (Ivantsoff, Crowley, Allen, 1987)
Status:
Native
The Unspecked hardyhead is listed under the Flora and Fauna Guarantee Act 1988. Under this legislation, the taking, possession or trading of the species is prohibited without a permit, licence or Governor-in-Council Order issued under the Act. A Recreational Fishing Licence is not a permit under the Act.
Description
Slender body. Small mouth with thick lips often not reaching the eye. Back colour is golden yellow to deep green. Upper sides and lower body light to white. No spots on sides. Conspicuous black, silvery band runs horizontally from the tip of the snout to the base of the tail.
Distribution
Most widely distributed of the Australian freshwater hardyheads. Occurs in Victorian waters connected and close to the Murray River. Widespread but patchy distribution; generally not common, though locally abundant.
Habitat
Found in a wide variety of habitats, including lagoons, swamps, lakes and slow-flowing reaches of river and creeks, usually in shallow, vegetated areas, but it may congregate where streams flow into still water.
Brief Biology
Known to reach 10 cm. Able to adapt to water temperatures from 9 to 28oC, and salinities between 3,000 and 9,000 p.p.m. Breeding season, from October to mid February. Eggs are laid at random over rocks, crevices and gravel.
Other Notes
Reported as good at mosquito control.
Common Name:
Murray Hardyhead
Other Name/s:
Mitchellian Freshwater Hardyhead
Scientific Name:
Craterocephalus auriatilis (McCulloch, 1913)
Status:
Native
The Murray hardyhead is listed under the Flora and Fauna Guarantee Act 1988. Under this legislation, the taking, possession or trading of the species is prohibited without a permit, licence or Governor-in-Council Order issued under the Act. A Recreational Fishing Licence is not a permit under the Act.
Description
Small eyes. Small oblique mouth with fleshy lips. Body colour varies, ranging from light brown to bright yellow with a distinct silvery to golden mid-body horizontal line. Belly may be iridescent green and gill covers silvery. The back and upper sides are darker because of fine speckling.
Distribution
Distribution in Victoria is limited to the Murray River system and within that system to the Robinvale - Kerang Lakes area. Not uncommon.
Habitat
Variety of habitats including slow-flowing lowland streams, lakes, billabongs and swamps, most frequently in weedy areas or over gravel bottoms.
Brief Biology
Known to exceed 9 cm, but most commonly found up to 7 cm. Can withstand a wide range of salinities, up to 100,000 p.p.m., or three times that of sea-water. Little is known of the life cycle, but ripe females have been collected from January to March. Believed to be omnivorous, taking both invertebrates and plant material.
Other Notes
An inconspicuous and shy fish, remaining near the bottom, known to congregate in large numbers where streams flow into still waters. Good at mosquito control.
Freshwater Fish of Victoria
is a series of brief information material on the native and introduced freshwater fish of Victoria's inland waters. Further, detailed reading on Hardyheads is contained in:
Freshwater Fishes of South-Eastern Australia
R M McDowall (Ed.)
A Guide to the Freshwater Fish of Victoria
Phillip Cadwallader & Gary Backhouse,
Department of Conservation and Environment
Australian Freshwater Fishes
John R. Merrick & Gunther E. Schmida
Biological Information for Management of Native Freshwater Fish in Victoria
J D Koehn, W G O'ConnorVFN #22 - Hardyheads
Prepared with the assistance of Gary Backhouse, Phillip Cadwallader and Tarmo Raadik
This publication may be of assistance to you but the State of Victoria and its officers do not guarantee that the publication is without flaw of any kind or is wholly appropriate for your particular purposes and therefore disclaims all liability for any error, loss or other consequence which may arise from you relying on any information in this publication.
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