Eastern Freshwater Cod (Maccullochella ikei), also known as Eastern Cod, are a freshwater fish belonging to the family Percichthyidae; they are not a true cod. Scientific classification or biological classification is how biologists group and categorize extinct and living species of organisms. ... Phyla Porifera (sponges) Ctenophora (comb jellies) Cnidaria Placozoa Subregnum Bilateria  Acoelomorpha  Orthonectida  Rhombozoa  Myxozoa  Superphylum Deuterostomia     Chordata (vertebrates, etc. ... Typical Classes Subphylum Urochordata - Tunicates Ascideiacea Thaliacea Larvacea Subphylum Cephalochordata - Lancelets Subphylum Myxini - Hagfishes Subphylum Vertebrata - Vertebrates Petromyzontida - Lampreys Placodermi (extinct) Chondrichthyes - Cartilaginous fishes Acanthodii (extinct) Actinopterygii - Ray-finned fishes Actinistia - Coelacanths Dipnoi - Lungfishes Amphibia - Amphibians Reptilia - Reptiles Aves - Birds Mammalia - Mammals Chordates (phylum Chordata) include the vertebrates, together with... Orders See text The Actinopterygii are the ray-finned fish. ... Families many, see text The Perciformes, also called the Percomorphi or Acanthopteri, include about 40% of all fish and are the largest order of vertebrates. ... Genera Bathysphyraenops (disputed) Bostockia Coreoperca Edelia Gadopsis Guyu Howella Lateolabrax Maccullochella Macquaria Nannatherina Nannoperca Percichthys Siniperca The Family Percichthyidae are known as the Temperate perches. ... The Maccullochella genus is a genus of large Australian predatory freshwater fish within the Percichthyidae family. ... In biology, binomial nomenclature is a standard convention used for naming species. ... Genera Bathysphyraenops (disputed) Bostockia Coreoperca Edelia Gadopsis Guyu Howella Lateolabrax Maccullochella Macquaria Nannatherina Nannoperca Percichthys Siniperca The Family Percichthyidae are known as the Temperate perches. ... Species Gadus morhua Gadus macrocephalus Gadus ogac This article is about codfish; for other meanings, see COD. Cod is the common name for the genus Gadus of fish, belonging to the family Gadidae, and is also used in the common name of a variety of other fishes. ...

Range

Eastern Freshwater Cod are native to the Clarence and Richmond Rivers and their tributaries, which are East Coast drainages found in eastern Australia. They are similar in appearance to Murray Cod, M. peelii peelii. At least three rivers called the Clarence River: Australia The Clarence River flows through Australia Canada/USA The Clarence River rises in the Yukon Territory of Canada and crosses back and forth across the border several times into the U.S. state of Alaska. ... The estuary of the Richmond River at Ballina The Richmond River is a river in the northeastern corner of New South Wales, Australia. ... Trinomial name Maccullochella peelii peelii (Mitchell, 1838) The Murray Cod (Maccullochella peelii peelii) is the largest freshwater fish in Australia. ...

Appearance and Size

Eastern Freshwater Cod are generally a yellow green to golden colour, overlain with a dense pattern of black to very dark green mottling. Eastern Freshwater Cod have been recorded to 41kg.

Habitat, Diet and Spawning

Eastern Freshwater Cod are found in clear, flowing rivers and streams with rocky beds and deep holes within the Clarence River system. The size of the rivers and streams they inhabit range from very small to very large.

Eastern Freshwater Cod are territorial and aggressive. They are known to prey upon other fishes, frogs, crustaceans and snakes. A long-lived, slow-growing species, they are gravely threatened by overfishing, habitat degredation and catastrophic natural events such as bushfires. Original populations in the Richmond River system are extinct, but have been re-established with fingerlings produced from broodfish from the Clarence River system. The term territory is also used in politics. ... Genera Afrana Amietia Amnirana Amolops Aubria Batrachylodes Ceratobatrachus Chaparana Conraua Discodeles Euphlyctis Fejervarya Hildebrandtia Hoplobatrachus Huia Indirana Ingerana Lankanectes Lanzarana Limnonectes Meristogenys Micrixalus Minervarya Nannophrys Nanorana Nyctibatrachus Occidozyga Paa Palmatorappia Platymantis Pseudoamolops Pterorana Ptychadena Pyxicephalus Rana Sphaerotheca Staurois Strongylopus Tomopterna Frogs are amphibians in the Order Anura, which includes true... Classes Class Branchiopoda Subclass Phyllopoda Subclass Sarsostraca Class Remipedia Order Enantiopoda Order Nectiopoda Class Cephalocarida Order Brachypoda Class Maxillopoda Subclass Mystacocarida Subclass Copepoda Subclass Branchiura Subclass Pentastomida Subclass Tantulocarida Subclass Thecostraca Infraclass Cirripedia Class Ostracoda Order Metacopina Subclass Myodocopa Subclass Podocopa Class Malacostraca Subclass Eumalacostraca Subclass Hoplocarida Subclass Phyllocarida The... Superfamilies and Families Henophidia Aniliidae Anomochilidae Boidae Bolyeriidae Cylindrophiidae Loxocemidae Pythonidae Tropidophiidae Uropeltidae Xenopeltidae Typhlopoidea Anomalepididae Leptotyphlopidae Typhlopidae Xenophidia Acrochordidae Atractaspididae Colubridae Elapidae Hydrophiidae Viperidae Snakes are cold blooded legless reptiles closely related to lizards, which share the order Squamata. ...

Eastern Freshwater Cod are now protected by law.

Eastern Freshwater Cod are sexually mature at 4 or 5 years old, and at sizes as small as 700 grams, the latter being markedly different to Murray Cod. This far smaller size at sexual maturity may be an adaptation to small, food-impoverished waterways. Eastern Freshwater Cod spawn in early spring when water temperatures reach 16 degrees, using rock structures as sites for the adhesive eggs. Most other aspects of their spawning, including the guarding of eggs and newly hatched larvae by the male fish, are similar to Murray Cod. It is important for anglers to avoid any accidental captures of Eastern Freshwater Cod in winter when they are developing their roe, or in early spring when spawning is occurring, as research indicates this results in resorbed roe or abandoned nests and a failed spawning effort. Anglers are not allowed to deliberately target Eastern Freshwater Cod. Trinomial name Maccullochella peelii peelii (Mitchell, 1838) The Murray Cod (Maccullochella peelii peelii) is the largest freshwater fish in Australia. ... Trinomial name Maccullochella peelii peelii (Mitchell, 1838) The Murray Cod (Maccullochella peelii peelii) is the largest freshwater fish in Australia. ...

Origins

Eastern Freshwater Cod are a separate species of Cod that originated from the Murray Cod (Maccullochella peelii peelii) that are present in tributaries of the Murray-Darling Basin on the western side of the Great Dividing Range. Murray Cod entered the headwaters of the Clarence River system through a natural river capture event somewhere between 0.8 and 1.7 million years ago, as estimated by DNA divergence rates. Subsequent isolation from Murray Cod populations, the founder effect, genetic drift and natural selection all led Eastern Freshwater Cod to diverge from and become a separate species to Murray Cod. (See allopatric speciation.) Trinomial name Maccullochella peelii peelii (Mitchell, 1838) The Murray Cod (Maccullochella peelii peelii) is the largest freshwater fish in Australia. ... Semi-arid grazing country near Burra Creek, South Australia The Murray-Darling Basin drains one-seventh of Australia and is by far the most significant agricultural area on that continent. ... The Great Divide runs around the entire eastern and south-eastern edge of Australia The Great Dividing Range (a. ... In geology, river capture is an event in which one river or stream captures or intercepts part of another. ... Space-filling model of a section of DNA molecule Deoxyribonucleic acid (DNA) is a nucleic acid that contains the genetic instructions specifying the biological development of all cellular forms of life (and many viruses). ... Trinomial name Maccullochella peelii peelii (Mitchell, 1838) The Murray Cod (Maccullochella peelii peelii) is the largest freshwater fish in Australia. ... The founder effect is an evolutionary phenomenon. ... Genetic drift is a mechanism of evolution that acts in concert with natural selection to change the characteristics of species over time. ... Natural selection is a process by which biological populations are altered over time, as a result of the propagation of heritable traits that affect the capacity of individual organisms to survive and reproduce. ... Trinomial name Maccullochella peelii peelii (Mitchell, 1838) The Murray Cod (Maccullochella peelii peelii) is the largest freshwater fish in Australia. ... Allopatric speciation (also known as Allopatry) is speciation by geographical isolation. ...

It is not clear whether Murray Cod only crossed the Great Dividing Range once or several times to found the four coastal cod populations present in four coastl river systems at the time of European settlement. Eastern Freshwater Cod may be the parent species of all coastal cod populations including Mary River Cod (Maccullochella peelii mariensis), another coastal cod species occurring in the Mary River in central Queensland, although this is not currently reflected in the taxonomy. See Mary River Cod for details. Trinomial name Maccullochella peelii peelii (Mitchell, 1838) The Murray Cod (Maccullochella peelii peelii) is the largest freshwater fish in Australia. ... The Great Divide runs around the entire eastern and south-eastern edge of Australia The Great Dividing Range (a. ... Trinomial name Maccullochella peelii mariensis Rowland, 1993 Mary River Cod (Maccullochella peelii mariensis) are a Maccullochella cod found in the coastal Mary River system of central Queensland, Australia. ... Trinomial name Maccullochella peelii mariensis Rowland, 1993 Mary River Cod (Maccullochella peelii mariensis) are a Maccullochella cod found in the coastal Mary River system of central Queensland, Australia. ...

Conservation

At the time of the first European settlement of the Australia in the 18th century, naturally occuring cod populations were present in four East Coast river systems: the Clarence and Richmond Rivers in northern New South Wales and the Brisbane and Mary Rivers in southern/central Queensland. The original cod populations of the Richmond and Brisbane River systems are unfortunately extinct due to the same factors that have endangered extant cod populations in the Clarence River (Eastern Freshwater Cod) and the Mary River (Mary River Cod): gross overfishing including with nets and explosives, gross habitat destruction and siltation, and whole-of-catchment scale bushfires and subsequent ash fish kills in the 1930s. (17th century - 18th century - 19th century - more centuries) As a means of recording the passage of time, the 18th century refers to the century that lasted from 1701 through 1800. ... Motto: Orta Recens Quam Pura Nites (Newly Risen, How Brightly You Shine) Nickname: First State, Premier State Other Australian states and territories Capital Sydney Government Governor Premier Const. ... Motto: Audax at Fidelis (Bold but Faithful) Nickname: Sunshine State/Smart State Other Australian states and territories Capital Brisbane Government Governor Premier Const. ... Trinomial name Maccullochella peelii mariensis Rowland, 1993 Mary River Cod (Maccullochella peelii mariensis) are a Maccullochella cod found in the coastal Mary River system of central Queensland, Australia. ...

Eastern Freshwater Cod were recognised as a potentially separate and endangered species of Cod in 1984, and were declared a protected species in that year. Subsequent research confirmed they are indeed a separate and endangered species of Cod; they remain a protected species.

A restocking programme was undertaken by the government of New South Wales in from 1984 to 1989. The government-run stocking programme was ill-advisedly closed after 1989 and contracted to a private operation, which produced and stocked fingerlings until the late 1990s. The Eastern Freshwater Cod stocking programme was then suspended after genetic research indicated inbred fingerlings with extremely poor genetic diversity, that could threaten the genetics of remnant wild populations, were being produced and stocked. Motto: Orta Recens Quam Pura Nites (Newly Risen, How Brightly You Shine) Nickname: First State, Premier State Other Australian states and territories Capital Sydney Government Governor Premier Const. ...

No Eastern Freshwater Cod are currently being bred or stocked.

The NSW fisheries department has allowed the private operation that produced Eastern Freshwater Cod fingerlings to retain broodfish and produce captive-reared Eastern Freshwater Cod for the table fish market - a decision that most people involved in conservation of Australian native freshwater fish consider indefencable and vehemently object to.

There are grave concerns over the future of all Eastern Freshwater cod stocks in the Clarence River system after the NSW Fisheries department allowed a foolhardy stocking of Australian Bass fingerlings from a completely different bio-region to proceed. The fingerlings were contaminated with and introduced the Banded Grunter (Amniataba percoides) to the lower reaches of the river. The Banded Grunter is an extremely aggressive small native fish species. It is feared Banded Grunter may yet invade the main freshwater reaches of the Clarence River system with devestating impacts on Eastern Freshwater Cod. Binomial name Macquaria novemaculeata (Steindachner, 1866) The Australian Bass, Macquaria novemaculeata is a species of fish in the family Percichthyidae that occurs in coastal waterways along the east coast of Australia, from east of Wilsons Promontory in Victoria east and north along the eastern seaboard to the rivers and...

References

Rowland, S.J. 1993. Maccullochella ikei, an endangered species of freshwater cod (Pisces: Percichthyidae) from the Clarence River System, NSW, and M.peelii mariensis, a new subspecies from the Mary River System, QLD. Records of the Australian Musuem 45: 121-145.