The very short answer to what caused the decline in eating rabbits in Australia is"Myxomatosis and Calicivirus".

For a more detailed answer you need some background on why eating rabbit became widespread in Australia to the extent that it is commonly called "underground mutton". Rabbit is not native to Australia and is considered one of Australia's most serious invasive pest species.

Although there were rabbits brought for food with the First Fleet in 1788, they were caged and did not prosper. In 1859 Thomas Austin released a small group of wild rabbits (between 7 and 24) on Barwon Park near Geelong to provide sport shooting. In 1866 14,253 rabbits were shot on Barwon Park.

Rabbits are prolific, they dig underground warrens, and they disperse rapidly. A doe rabbit matures at 3-4 months produces 7 litters a year with each litter of about 5 kits. Rabbits prefer well watered country and green feed (the best arable land) but will still heavily colonise arid land, and they have few natural predators in Australia. Once introduced, they spread like a plague stripping the ground of vegetation. They spread at 10-15 kms per year in wet forested country and 100 kms per year in open rangeland.

By 1879, 20 years after the initial release, the infestation covered Victoria, The Eastern half of South Australia and Southern New South Wales and the N.S.W. government was offering a large reward for any new method of eradication. By 1901 there was a Royal Commission to investigate the problem and Western Australia had commenced building the 1,139 mile long Rabbit-Proof Fence (completed 1907 and still maintained) to protect the western part of the state from the rest of Australia, There are also two more connected rabbit proof fences further subdividing W.A. for a total length of 2,023 miles. By the 1920s, about 60 years after their initial release, rabbits were present in extremely high numbers through most of the southern part of Australia and presented a high cost to the Australian economy which was largely agricultural.

Rabbit as food was not considered a delicacy. It was “poor man’s tucker”. They were available in high numbers, easy to kill by trapping, shooting or using ferrets, so anyone who lived outside of a major city could get their own or kill them commercially for sale to a butcher. Many baby boomers would have eaten it.

The Myxoma virus was first suggested as a biological control for rabbits in 1919, followed by laboratory testing in 1926. In 1934 and 1936 further laboratory testing was carried out to ensure the virus did not effect humans, native animals or domestic stock. And field trials were commenced in the arid areas of South Australia. The field trials were considered unsuccessful as the virus would wipe out individual warrens but not spread from warren to warren. It was recommended for use only in special conditions In late 1949 further field trials were held in the Murray Valley in the area around Albury and after heavy rains in 1950 Myxomatosis began spreading in epidemic rates, killing rabbits all along the wet areas of the Murray valley, the Lachlan, the Murrumbidgee and up the Darling. It was found that the virus was heavily dependant on insect vectors to spread and the heavy mosquito growth after the rains was carrying it from warren to warren while rabbit fleas were spreading it within warrens. By 1953, rabbit numbers in Australia had crashed and Australian wool and meat production soared.. The initial death rate was 99% of infected rabbits although the reliance on insects meant that the infection did not spread well in arid areas so there was always going to be a pool of uninfected rabbits. The scientists in the myxomatosis project predicted that surviving rabbits would develop immunity to the virus and once the death rate dropped to 90% we could expect a resurgence in rabbit numbers. By 1995 rabbit numbers had climbed back to 300 million.

By then, the Commonwealth Scientific and Industrial Research Organisation (CSIRO) was investigating Rabbit Calicivirus Disease, a disease that only effects European rabbits. It had first been reported in China in 1984 and soon after in other countries. In 1991 the CSIRO started testing it in a quarantine laboratory near Geelong. In 1995 a quarantine facility was set up for field testing the virus on Wardung Island off the coast of South Australia with an expected release in 1998 however after 6 months the Calicivirus “escaped” quarantine and rapidly spread on the mainland. It is expected that it will lose effectiveness over time as did the myxoma virus and to extend the effectiveness of the calicivirus a new variant (K5) was released in 2017.

So there are much fewer wild rabbits than there were in the 1920s. You rarely see children hunting them. There isn’t all that much meat on one compared with a battery chicken. They are no longer cheap meat. You can still buy wild rabbit from some butchers but you would have to search for it.

• McKay A, 1976, ‘Myxomatosis’, In: Surprise and Enterprise, Fifty Years of Science for Australia, White F, Kimpton D (eds), CSIRO Publishing, pp.38-39.

• Blythe M, 1992 and 1993, Interviews with Australian Scientists: Professor Frank Fenner ‘ Microbiologist and virologist (Australian Academy of Science)