Climbing galaxias
Encyclopedia
The Climbing galaxias or the Koaro (Galaxias brevipinnis), is a fish of the family
Galaxiidae found in Australia
, New Zealand
and nearby islands. The name Climbing galaxias is used in Australia, and Koaro in New Zealand. Further vernacular names include Short-finned galaxias, Broad-finned galaxias, Cox's mountain galaxias, and Pieman galaxias.
species because of its shape. It is elongate and slender, shaped almost like a tube. The sides and back are covered in a variable pattern of golden blotches and bands that gleam and glitter in the sun, making the Climbing galaxias a very attractive fish indeed.
, a closely related galaxiid. They inhabit mainly clear streams, often deeply shaded and relatively fast-flowing, although it sometimes occurs in lakes, particularly in Tasmania. Climbing galaxias also have the ability to penetrate well inland in many river systems, and thus have a more widespread distribution than the other whitebait species.
A major distinguishing feature of this species is its ability to climb up very steep surfaces such as waterfall
s, wet rocks and the sluices of hydro dam
s, and this gives rise to one of its common names. Even juveniles of the species are capable of climbing up and over the sides of buckets after being trapped in whitebait nets.
Climbing ability is not unique among galaxias species, but it reaches its greatest expression in the Climbing galaxias which have special features that enhance their climbing abilities. The downward orientation of their fins and the strong, backward-facing ridges on the front part of their fins possibly contribute to this ability.
are believed to be washed downstream to the sea
where the young live for about 6 months before returning to freshwater
as part of the large mixed species schools known as whitebait. They were once part of a commercial whitebait fishery in Tasmania, but now fishing for them has been restricted to recreational anglers with significant restrictions on allowable tackle and methods. Land-locked populations have a similar lifestyle except that the young spend the first part of their life in inland lake
s and backwaters etc.
s of invertebrate
s including aquatic and terrestrial insect
s, mayfly
, caddisfly larva
e, and amphipods.
and Kangaroo Island
in South Australia
, through coastal Victoria
including Wilsons Promontory
, Tasmania
, Flinders
and King Islands and up the New South Wales
coast to around Sydney
, as well as New Zealand
including the Chatham
, Auckland
and Campbell Islands.
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Galaxiidae found in Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
, New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
and nearby islands. The name Climbing galaxias is used in Australia, and Koaro in New Zealand. Further vernacular names include Short-finned galaxias, Broad-finned galaxias, Cox's mountain galaxias, and Pieman galaxias.
Appearance
The Climbing galaxias is unlikely to be confused with the other diadromous whitebaitWhitebait
Whitebait is a collective term for the immature fry of fish, typically between 25 and 50 millimetres long. Such young fish often travel together in schools along the coast, and move into estuaries and sometimes up rivers where they can be easily caught with fine meshed fishing nets...
species because of its shape. It is elongate and slender, shaped almost like a tube. The sides and back are covered in a variable pattern of golden blotches and bands that gleam and glitter in the sun, making the Climbing galaxias a very attractive fish indeed.
Lifestyle
These fish live a basically benthic lifestyle and in most respects behave like the common galaxiasCommon galaxias
The common galaxias or the inanga , is a species of fish from the galaxiid family that is very widespread in the southern hemisphere. It is a slim narrow fish with a forked tail and as an adult it lives in freshwater rivers and lakes. Common galaxias grows to a length of 40 to 120 mm, but can grow...
, a closely related galaxiid. They inhabit mainly clear streams, often deeply shaded and relatively fast-flowing, although it sometimes occurs in lakes, particularly in Tasmania. Climbing galaxias also have the ability to penetrate well inland in many river systems, and thus have a more widespread distribution than the other whitebait species.
A major distinguishing feature of this species is its ability to climb up very steep surfaces such as waterfall
Waterfall
A waterfall is a place where flowing water rapidly drops in elevation as it flows over a steep region or a cliff.-Formation:Waterfalls are commonly formed when a river is young. At these times the channel is often narrow and deep. When the river courses over resistant bedrock, erosion happens...
s, wet rocks and the sluices of hydro dam
Dam
A dam is a barrier that impounds water or underground streams. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees are used to manage or prevent water flow into specific land regions. Hydropower and pumped-storage hydroelectricity are...
s, and this gives rise to one of its common names. Even juveniles of the species are capable of climbing up and over the sides of buckets after being trapped in whitebait nets.
Climbing ability is not unique among galaxias species, but it reaches its greatest expression in the Climbing galaxias which have special features that enhance their climbing abilities. The downward orientation of their fins and the strong, backward-facing ridges on the front part of their fins possibly contribute to this ability.
Lifecycle
G. brevipinnis eggsEgg (biology)
An egg is an organic vessel in which an embryo first begins to develop. In most birds, reptiles, insects, molluscs, fish, and monotremes, an egg is the zygote, resulting from fertilization of the ovum, which is expelled from the body and permitted to develop outside the body until the developing...
are believed to be washed downstream to the sea
Sea
A sea generally refers to a large body of salt water, but the term is used in other contexts as well. Most commonly, it means a large expanse of saline water connected with an ocean, and is commonly used as a synonym for ocean...
where the young live for about 6 months before returning to freshwater
Freshwater
Fresh water is naturally occurring water on the Earth's surface in ice sheets, ice caps, glaciers, bogs, ponds, lakes, rivers and streams, and underground as groundwater in aquifers and underground streams. Fresh water is generally characterized by having low concentrations of dissolved salts and...
as part of the large mixed species schools known as whitebait. They were once part of a commercial whitebait fishery in Tasmania, but now fishing for them has been restricted to recreational anglers with significant restrictions on allowable tackle and methods. Land-locked populations have a similar lifestyle except that the young spend the first part of their life in inland lake
Lake
A lake is a body of relatively still fresh or salt water of considerable size, localized in a basin, that is surrounded by land. Lakes are inland and not part of the ocean and therefore are distinct from lagoons, and are larger and deeper than ponds. Lakes can be contrasted with rivers or streams,...
s and backwaters etc.
Diet
These fish are generalised carnivoreCarnivore
A carnivore meaning 'meat eater' is an organism that derives its energy and nutrient requirements from a diet consisting mainly or exclusively of animal tissue, whether through predation or scavenging...
s of invertebrate
Invertebrate
An invertebrate is an animal without a backbone. The group includes 97% of all animal species – all animals except those in the chordate subphylum Vertebrata .Invertebrates form a paraphyletic group...
s including aquatic and terrestrial insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
s, mayfly
Mayfly
Mayflies are insects which belong to the Order Ephemeroptera . They have been placed into an ancient group of insects termed the Palaeoptera, which also contains dragonflies and damselflies...
, caddisfly larva
Larva
A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...
e, and amphipods.
Distribution
Their distribution extends to coastal streams in southeastern Australia from AdelaideAdelaide
Adelaide is the capital city of South Australia and the fifth-largest city in Australia. Adelaide has an estimated population of more than 1.2 million...
and Kangaroo Island
Kangaroo Island
Kangaroo Island is Australia's third-largest island after Tasmania and Melville Island. It is southwest of Adelaide at the entrance of Gulf St Vincent. Its closest point to the mainland is off Cape Jervis, on the tip of the Fleurieu Peninsula in the state of South Australia. The island is long...
in South Australia
South Australia
South Australia is a state of Australia in the southern central part of the country. It covers some of the most arid parts of the continent; with a total land area of , it is the fourth largest of Australia's six states and two territories.South Australia shares borders with all of the mainland...
, through coastal Victoria
Victoria (Australia)
Victoria is the second most populous state in Australia. Geographically the smallest mainland state, Victoria is bordered by New South Wales, South Australia, and Tasmania on Boundary Islet to the north, west and south respectively....
including Wilsons Promontory
Wilsons Promontory
Wilsons Promontory is a peninsula that forms the southernmost part of the Australian mainland and is located at . South Point at is the southernmost tip of Wilsons Promontory and hence of mainland Australia...
, Tasmania
Tasmania
Tasmania is an Australian island and state. It is south of the continent, separated by Bass Strait. The state includes the island of Tasmania—the 26th largest island in the world—and the surrounding islands. The state has a population of 507,626 , of whom almost half reside in the greater Hobart...
, Flinders
Flinders Island
Flinders Island may refer to:In Australia:* Flinders Island , in the Furneaux Group, is the largest and best known* Flinders Island * Flinders Island , in the Investigator Group* Flinders Island...
and King Islands and up the New South Wales
New South Wales
New South Wales is a state of :Australia, located in the east of the country. It is bordered by Queensland, Victoria and South Australia to the north, south and west respectively. To the east, the state is bordered by the Tasman Sea, which forms part of the Pacific Ocean. New South Wales...
coast to around Sydney
Sydney
Sydney is the most populous city in Australia and the state capital of New South Wales. Sydney is located on Australia's south-east coast of the Tasman Sea. As of June 2010, the greater metropolitan area had an approximate population of 4.6 million people...
, as well as New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
including the Chatham
Chatham Islands
The Chatham Islands are an archipelago and New Zealand territory in the Pacific Ocean consisting of about ten islands within a radius, the largest of which are Chatham Island and Pitt Island. Their name in the indigenous language, Moriori, means Misty Sun...
, Auckland
Auckland Islands
The Auckland Islands are an archipelago of the New Zealand Sub-Antarctic Islands and include Auckland Island, Adams Island, Enderby Island, Disappointment Island, Ewing Island, Rose Island, Dundas Island and Green Island, with a combined area of...
and Campbell Islands.
External links
- Koaro NIWA June 2010
- Climbing galaxias Native Fish Australia