Introduction to Australia's Fishes

Fishes are the largest and most diverse group of vertebrate animals, with more than 32,500 valid described species (Eschmeyer & Fong 2013). This is many, many more than the combined total of all other vertebrates (amphibians, reptiles, birds and mammals). 

Under the term "fishes" we include the primitive jawless hagfishes and lampreys, sharks, rays and chimaeras, and the many and diverse groups of bony fishes.

White (1790) described the first Australian fishes that were actually collected in Australia. Although some wide-ranging species with distributions that include Australia had already been described, White's eight species came from Botany Bay, rather than from elsewhere. Our diverse and often unique fish fauna now numbers more than 5000 species, and we're still counting.

For those interested in reading more about the discovery of Australia's fishes, find a copy of Brian Saunders beautifully written and illustrated Discovery of Australia's fishes : a history of Australian ichthyology to 1930.

Australia’s marine environment is enormous, covering an area of about 9 million km2 with more than 36,000 km of coastline (including external territories outside Antarctica). That figure actually needs updating as Australia recently extended its maritime boundaries.

Habitats range from the coral reefs and tropical estuaries of the north, to cold temperate rocky reefs along the southern coast, plus oceanic and deep sea habitats beyond the continental slope. As a result, Australia has one of the largest and most diverse marine fish faunas in the world.

Fishes not only come in an impressive array of shapes and sizes – they live in almost all aquatic environments in Australia. These include the hot desert springs, freshwater rivers, streams and lakes found on land, to mangrove swamps, coral reefs, seagrass meadows, turbulent coastal kelp forests, and the twilight zone and abyss of the deep-sea.

The freshwater component of the fauna is very small relative to the numbers of freshwater fishes elsewhere in the world (Merrick 2006). Although small in number however, our fauna is diverse and unique, and includes jawless lampreys, sharks, sawfishes, the iconic lungfish, eels, galaxiids, hardyheads, rainbowfishes, cods, grunters, gobies, gudgeons and soles. What's more - recent molecular studies have 'uncovered' a many new freshwater species, including galaxiids, river blackfish, pygmy perch among others.

Like fishes everywhere, the distributions of Australia’s fishes are determined by their biology, behaviour and historical origins. Most (nearly 75%) live in tropical marine environments. Northern Australia sits on the edge of the ‘Coral Triangle’, the Indo-Australian Archipelago, which has the highest biodiversity of marine fishes in the world.

Almost a quarter of Australia's fishes are endemic, meaning that they are found nowhere else in the world - and most of these (60%) live in cooler southern waters (Hoese et al. 2006).

The total number of Australian fishes continues to rise each year when new species are discovered or when species known to occur elsewhere are found in our waters.


References

Eschmeyer, W.N. & Fong, J.D. 2013. Species of Fishes by family/subfamily. On-line version, Updated 4 January 2013.http://research.calacademy.org/research/ichthyology/catalog/SpeciesByFamily.asp

Hoese, D.F., Bray, D.J., Paxton, J.R. & Allen, G.R. 2006. Introduction, pp 1-27. In Beesley, P.A. & A. Wells (eds) Zoological Catalogue of Australia, Volume 35. Australia : ABRS & CSIRO Publishing Parts 1-3, 2178 pp.

Merrick, J.R. 2006. Australasian freshwater fish faunas: diversity, interrelationships, radiations and conservation, pp.195-224. In Merrick, J.R., M. Archer, G.M. Hickey and M.S.Y. Lee (eds) Evolution and Biogeography of Australasian Vertebrates. Oatlands, NSW: Auscipub Pty Ltd, pp. xxvii + 942.

Paxton, J.R., G.R. Allen & D.F. Hoese. 2006. Australian marine fishes: zoogeography, endemics and conservation, pp. 185-194. In Merrick, J.R., M. Archer, G.M. Hickey & M.S.Y. Lee (eds) Evolution and Biogeography of Australasian Vertebrates. Oatlands, NSW: Auscipub Pty Ltd, pp. xxvii + 942.

Saunders, B.G. 2012. Discovery of Australia's Fishes. A History of Australian Ichthyology to 1930. CSIRO Publishing, Collingwood, Victoria : 570pp.

White, J. 1790. Journal of a voyage to New South Wales. Debrett, London. 299pp.


Author: Dianne J. Bray