The Clarence River cod, eastern cod, is a large freshwater fish with a deep, elongate body, reaching a maximum length of over 1m and a maximum weight between 40 and 50kg. Adults are generally olive-green to yellow-green in colour, with dark, and often reticulated, mottling on the back.

Threats

A number of historical events appear to have significantly contributed to the decline of eastern freshwater cod. These include habitat degradation and fish kills associated with dynamiting during the construction of the north coast railway in the late-1920s and in the late-1930s, residents in the upper Clarence River catchment reported the use of dynamite within the vicinity of Clarence River Gorge as a method for catching fish, but in effect killing thousands of fish. This non-selective technique is likely to have resulted in localised extinction of the eastern freshwater cod.

Quollity Conservation Hub's Vulnerability Score:

22

To help compare the relative vulnerability of different species, we have developed a scoring system based on biological and ecological characteristics that influence a species' ability to survive and recover from environmental change and natural disasters.

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The framework is adapted from assessment methods used by conservation experts following the Black Summer bushfires to help identify species most in need of conservation action, research, and recovery funding.

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Each species is assessed using a range of factors, including its conservation status, lifespan, reproductive rate, habitat and dietary requirements, ability to disperse or recover after fire, and the number and severity of threats it faces.

In general, the higher a species' score, the greater its overall vulnerability and risk of decline or extinction.

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Like all conservation assessments, this scoring system is limited by the information currently available. Many threatened species remain poorly studied and receive limited research funding, meaning some assessments rely on the best available scientific knowledge or information from closely related species. As new research becomes available, scores may be updated to reflect our improved understanding.