Author: Paul Humphries. With contributions by Katherine Doyle, Cameron G. Mc Gregor and Minda W. Murray. Illustrations by W. Howard Brandenburg
Publisher: CSIRO Publishing 2023
Reviewed by: Ricki Nash, NPA Environmental Book Club
About the Author: Associate Professor Paul Humphries is a River and Fish Ecologist based with the Gulbali Institute at Charles Sturt University (Albury-Wodonga). His work and research spans 40 years focusing on the early life cycles of freshwater fish, river ecology and flows, with a particular interest in historical ecology associated with the Murray-Darling Basin.
The Life and Times of the Murray Cod is a comprehensive book devoted to one of Australia’s best known freshwater fish, based on not just the author’s experiences, but also information from Fishery Inspectors, scientific research and from First Nations Peoples, the latter who have shared a unique experience with the species for thousands of years.
For ease of reading the book is divided into five parts, covering such aspects as the Murray Cod’s origins, its biology, people and their relationships with the species, the role of fisheries- both commercial companies and recreational fishermen, and finally conservation measures.
Murray Cod description and distribution
Some of the highlights include from Part 1 relating to the Murray Cod’s (Maccullochelia peelii) origins, which is thought by scientists using the fossil record to lie west of the Great Dividing Range during the Miocene period (between 23-5 mya). Today the species is endemic to the Murray-Darling River Basin along with three other distinct species from the genus Maccullochelia which includes the Trout Cod (Macquarie River), the Mary River Cod located north of Brisbane and the Eastern Freshwater Cod, between Northern NSW and the Queensland border.
In Part 2 readers learn that the Murray Cod favours either the main channels of freshwater rivers where the flow is slower or side channels and lagoons in preference to still water such as dams. The advent of GPS tagging and tracking has provided scientists with greater insight as to the distance covered by the species which can be as much as 1,000km.
Another interesting fact relates to the role of the male Murray Cod when caring for young fish. Prior to spawning, it looks up and downstream for the most suitable place for the eggs to be deposited, such as on sandbanks or on submerged logs, with the latter providing protection from predation. In addition, it also looks out for future food resources needed by juveniles such as micro and macro invertebrates.
It takes 5 years for the fish to reach maturity and they continue to grow throughout their lives often attaining a lifespan of 50 years or more, weighing up to 100kg and measuring 1.8m in length.
As adults, the species is characterised by a large gaping mouth allowing them to capture swans, ducks, other Cod and mussels, with shells of the latter being regurgitated after the soft fleshy bits are removed. When recreational and commercial fishing for Murray Cod became popular, special heavy duty fishing lines together with metal aeroplane spinners were developed to catch the fish. However, many anglers still preferred bait fishing and today recreational fishermen are encouraged to observe the “catch and release” rules for conservation purposes.
Stories abound about the Walgett Murray Cod being the largest fish ever caught in 1902, weighing 82.5 kg and measuring 1,830mm in length! Despite exhaustive efforts by the author, he was unable to find any credible information, scientific or otherwise to confirm the truth of this story.
The importance of Murray Cod to First Nations Peoples
In Part 3, the author delves into the relationships which people experienced with the Murray Cod such as First Nations Peoples who view it as sacred and belonging to Country where everything is interconnected. The Murray Cod was (and is) more than just a food source, being thought of as a cultural keystone species, and for some First Nations Peoples, it is their totem and thus seen as a knowledge keeper. For those First Nations Peoples who did partake in fishing, this was done by either spearing the Cod from canoes or when standing on the riverbank, using nets or constructing a system of weirs in a smaller tributary of the main river such as the Fish traps seen today on the Barwon River at Brewarrina. In addition, First Nations Peoples have been crucial for the survival of the Murray Cod and river ecosystems which is evidenced by the ways in which they modified river flows by cutting into the riverbanks to allow water to move into wetlands and billabongs. In this way these ecosystems were sustained and it also made fishing easier.
Early explorers like John Oxley on his journey along the Lachlan River was one of the first to catch and describe the fish as being “speckled with brown, blue and yellow spots, like a leopard’s skin”, weighing 30kg.
However, Charles Sturt and Thomas Mitchell weren’t so successful with fishing, but did record the methods used by First Nations People to catch Murray Cod, and it was these observations together with those made by the early settlers which ultimately led to the establishment of commercial fishing companies along the Murray River.
The rise of commercial and recreational fishing
In Part 4 an American, named Joseph Waldo Rice seized on the opportunity in 1856 to develop an inland fishery company to support the local people and the goldminers in Bendigo. His Fishery was based on a model developed by someone, according to the author, who worked for the “The Argus” and possibly lived on the Murray River or at Echuca, but who also knew about the methods deployed by First Nations Peoples to catch freshwater organisms such as fish, yabbies, crayfish etc.
Rice’s Company was initially established on an island in the middle of Lake Moira and became known as the Lake Moira Fishing Company, but because it was prone to being flooded, it eventually moved to the Victorian side of the Murray and was renamed the Murray River Fishing Company. During the early years, Rice employed First Nations Peoples because he knew of their fishing prowess, especially with Murray Cod. By 1862 the Company employed 6 men, and 2-3 tonnes of fish were being transported to Bendigo and the Melbourne markets overnight as refrigeration had not yet been invented.
Such was the popularity and what seemed like a never-ending supply of Murray Cod and other fish, Commercial Fishing Companies were also established in South Australia and Lake George just north of Canberra. During the 1850s, a local landowner stocked one end of the Lake with Murray Cod, as well as Silver and Golden Perch with anglers allowed to take as much as they wanted. However, the drought of 1890-1900 saw Lake George become dry, resulting in a large fish kill and the demise of the Fishing Company.
During the early 1920s European Carp and Perch became a major problem in the river systems and concerns were expressed about overfishing especially with the use of bag-netting, which captured all manner of aquatic life. This resulted in several Royal Commissions between 1892-96 which saw bag-nets banned.
As colonisation expanded along the Murray and other major river systems, the traditional owners, the Yorta-Yorta Peoples, were displaced from Country with many forced to live at Malaga Aboriginal Mission Station, not far from Moama.
During the 1960s fishing publications proliferated, with much press given to the benefits of recreational fishing for everyone, along with advances in fishing accessories including nylon lines. The aluminium boat, frequently used by fishermen, was replaced by a flat-bottomed version, to afford fishermen easier access to the more difficult parts of the river.
Long-term impacts of river management on Murray Cod
However, in Part 5 we learn that by 1996 Murray Cod populations had fallen dramatically from overfishing, with the species listed as Critically Endangered on the IUCN list. In the early 2000s commercial fishing on inland rivers ceased in Victoria, South Australia and NSW, apart from the Coorong in the lower reaches of the Murray River. By 2012, it was listed as of “least concern”.
Some of the reasons for the Cod’s decline can firstly be attributed to First Nations Peoples’ removal from their river country, where for thousands of years they had practiced sustainable fishing methods and cared for Country. Secondly, as colonial settlements expanded, so too did land clearing which saw sediment washed into creeks and onto the river’s floodplains with gold mining adding to sediment runoff. Thirdly, past practice saw submerged logs removed from rivers, but today it is recognised the important role these play in providing fish habitat. Fourthly, the introduction of common carp into the river systems resulted in damage to the aquatic areas by increasing the turbidity, and together with the construction of weirs and locks along the Murray, resulted in alterations to the river’s flows. Today with the effects of climate change, there have been more blackwater incidents resulting in large fish kills, including that of the Murray Cod.
According to the author, the answers for all of the above lies in the fact that firstly, First Nations Peoples should be involved with the conservation of the Murray Cod because of its cultural importance to them, along with the river ecosystems. Secondly, in order to facilitate better movement of the fish throughout the rivers, weirs and locks need to be dismantled. And finally, work with the natural climate systems by making use of events such as flooding, as this aids in the cleansing of the river by flushing out the accumulated silt, and allows juvenile fish to be moved to other parts of the system.
In conclusion
The Life and Times of the Murray Cod is a fascinating story, bringing the reader to a greater understanding of a truly remarkable species. Although it was nearly brought to the brink of extinction, it is a reminder to all of us who care enough about nature, whether it be birds, koalas or a particular landscape which supports unique biodiversity, the importance of being vigilant and to stand up against those who seek to destroy it for their own vested interests.
Footnote: It was a pleasure to be given the opportunity to write a review because in 2023 I was an undergraduate student in Paul’s class studying Animal Diversity. Fish were one of the topics including a practical session which involved a dissection! His passion about all the subject material was unwavering and an inspiration for all students.