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Step some 30 years back in time. Rabbits had been a problem but appeared to be under control after years of astute use of rabbiters and dogs. One of the last batches of possums was being released into our forests for fun and fur. Deer were in numbers only sufficient to accommodate the hunters; there was the odd goat shoot, with organised culling in some areas; but by and large we were not overrun with animal pests. I do not recall that feral cats were a problem back then either.
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P. Loague (1993) studied this question.
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