Blade ploughs as an alternative to tined rippers for rabbit warren destruction in semi-arid areas.

Abstract

A tractor-mounted blade plough was used to control rabbits in semi-arid South Australia by destroying their warrens. This implement was compared with a conventional two-tine ripper on the basis of effectiveness and cost. The blade plough was slightly less effective (overall mean 88% warrens destroyed) than the ripper (91% destroyed) three weeks after treatment but this difference was not significant. Warrens treated with the blade plough also had a slightly higher rate of reopening although the difference between treatments was not significant until 54 weeks after treatment. The blade plough was significantly faster in destroying warrens (mean 6.93 min cf. 9.88 min) despite frequent bogging of the tractor. The choice of a more suitable tractor should overcome this problem. Costs were similar but a small saving can be made by using a blade plough if a suitable tractor is already owned by the landholder. Including one follow-up treatment the cost of destruction per warren was $2.30 with the blade plough compared with $2.61 for the ripper. For properties where stock numbers are restricted, the return on an investment in rabbit control was estimated to be 13% per annum for the blade plough and 12% per annum for the ripper. Where stock numbers can be increased returns should be greater.