Murray Cod

The Murray cod (Maccullochella peelii peelii) is Australia's largest freshwater fish. Growing to a maximum recorded size of 6 feet and 250 lbs, almost every country pub in South Eastern Australia will contain a mounted specimen, and myriad tales of the one that got away.

Description

The Murray cod is robust and barrel-shaped, with a blunt, sloping head, cavernous mouth and small eyes. Colouration varies depending on water clarity - the murkier the water, the more lightly colored the fish. Most Murray cod are olive-green to yellow-green on the back, and creamy-yellow on the belly. The back is covered with darker green mottling. The dorsal fin is spiny.

Habitat

Runs the gamut of Australian waterways, from mountain streams to large, sluggish rivers with deep holes. Cod tend to prefer areas with plenty of cover such as fallen trees, stumps, clay banks and overhanging vegetation. Murray Cod are territorial, and will return to the same place after spawning.

Distribution

Widespread throughout the Murray- Darling river system, although massively reduced in abundance compared to the original population. Murray cod were originally plentiful and supported a substantial commercial fishery in the late 19th century and early 20th century. Prior to European colonisation the Koori population were able to exploit the species as a major source of food using relatively simple technologies due to the piscatorial superabundance.

The plunge in Murray cod numbers is attributed to multiple causes, the most significant of which has been identified has been the damming and canalization of the majority of the rivers in the Murray-Darling basin. This has resulted in substantial changes to the flow of virtually all rivers in the system. In addition, the dams and weirs themselves provide a physical barrier to fish migration. Grazing, soil erosion, salinity and the removal of in stream debris have also resulted in a reduction of suitable habitat for native fish in general and Murray cod in particular. Angling and commercial fishing have had an effect, but it is insignificant next to the other factors and is not considered to be of concern under the present regulatory framework.

Murray cod are a popular sporting fish and have been stocked into reservoirs throughout Queensland, New South Wales and Victoria. Some restocking of river populations has occurred but the most important tool in restoring cod populations to their former glory is environmentally friendly management of the river systems.

Reproduction

Murray Cod have been known to swim upstream 60 miles or more before breeding in spring and return to their original territory afterwards. Breeding is believed to be triggered by a heady combination of increasing daylight hours, changes in water temperature and flooding, but still remains somewhat of an unknown. Provided with appropriate shelter, cod will breed in earthen dams in captivity, but not concrete ponds. This has given rise to a burgeoning aquaculture industry.

Diet

Murray cod eat anything that moves - other fish, freshwater crayfish, yabbies, shrimp, freshwater mussels, frogs, water birds, small marsupials, tortoises and other reptiles. Rumour has it that the largest cod ever caught was lured by a strip of kangaroo meat on a piece of hooked high-tensile wire. There is something vaguely frightening about a freshwater fish with a taste for one of the national emblems.

Angling

Regarded as Australia's premier freshwater angling species, the powerful Murray cod can be a difficult customer. The tendency of Cod to head upstream, and towards the closest snag when hooked lead the compleat angler to use heavy tackle and lines with breaking strains greater than 50lbs.

Cod respond well to large baits, lures, and a well placed fly. Size and bag limits and closed seasons apply in all Australian states, so check your local authority for details. Most angling clubs recommend catch and release when fishing for Murray cod, especially with large fish which are important breeding stock for the species and are less palatable.

Eating

Murray cod make for excellent eating in the smaller legal sizes. Smaller fish can be filleted, and cooked as steaks or whole fish. It has a relatively neutral flavour and firm flesh that is ideal for either Western or Asian cooking. Larger fish tend to be oilier and are better steaked and grilled.

bibliography

• http://www.nativefish.asn.au/cod.html
• http://www.ea.gov.au/water/basins/murray-cod/index.html
• http://www.fisheries.nsw.gov.au/