Alternatives ‘not dealt with adequately by pest council’

Press, 26 April 1983, Page 39

Alternatives ‘not dealt with adequately by pest council’

The Nature Conservation Council opposed the reintroduction of myxomatosis to New Zealand, said the chairman, Professor Carolyn Burns, in Wellington. A report commissioned by the council said that while the Agricultural Pest Destruction Council’s assessment covered the reasons why myxomatosis could be reintroduced, it dealt inadequately with alternative views. Zoologists were divided as to the medium-term and long-term effectiveness of myxomatosis in reducing rabbit numbers, said the Nature Conservation Council’s report. Although in the short-term rabbit numbers would be reduced dramatically, experience in Britain and Australia had shown that 20 to 30 years after the introduction of the disease to those countries rabbit numbers were higher there than in most parts of New

Zealand. This was probably caused by the attenuation of the virus in the field and buildup of resistance to the disease in the rabbit population. Rabbit numbers in most parts of New Zealand were low and were being controlled by cats, weasels and stoats, and by pest destruction boards funded, in part, by local farmers. If myxomatosis was reintroduced the farmers might well be reluctant to continue financing the boards and their considerable expertise would be lost. The admittedly serious problem of rabbit numbers in Central Otago was seen as a symptom of land management practices in the area, said the report. The balance between climate, pasture management, and rabbit numbers in a dry area such as Central Otago was particularly fragile.

The report emphasised that once myxomatosis was introduced to New Zealand it was here “for good,” and that any possible long-term problems should be carefully researched before the step was taken. Although the direct cost of rabbit destruction could be reduced in the short term, a continuing and expensive research programme would be needed to monitor and manipulate the effects of the disease. Farmed and pet rabbits could be inoculated against myxomatosis but this would not guarantee their immunity, and there could be heavy losses of caged rabbits. It was also likely that there would be a public aversion to eating rabbits once the disease was established, said the reoort. The symptoms* of advanced myxomatosis were

unsightly and would be disturbing to many people, and it was likely that animal rights groups would strongly oppose the introduction of the disease. “There have been suggestions in the news media that individuals may illegally introduce myxomatosis to New Zealand, probably from Australia. If this happens the consequences could be very serious as the virus would probably be an attenuated field strain which would be unlikely to give good rabbit control even in the short term, and may encourage resistance to the virus to build up quickly in wild rabbits,” the report concluded. The Nature Conservation Council will inform the Agricultural Pest Destruction Council of its opposition to the introduction of myxomatosis.