The effect of concentration on the ingestion of '1080' poisoned baits by the rabbit

Abstract

Cage experiments on the feeding of wild rabbits, Oryctolagus cuniculus (L.), with carrot and oats poisoned with "1080" showed no evidence of any poisonrepellency, and suggest that the poison may even be attractive. Reduction of food intake as compared with previous unpoisoned feeds was due to the onset of toxic symptoms; the delay before this occurred varied with concentration, but even at high levels (0.2 per cent.) feeding continued for at least 10 min. With concentrations between 0.02 per cent, and 0.2 per cent. this latent period was relatively constant and, in consequence, so was the intake of poisoned bait. It is suggested that the normal field strength of "1080" for use with carrot could be reduced to 0.02 per cent. without impairing efficiency or requiring more bait to be laid, since consumption would be substantially the same. This would greatly reduce the hazard to stock and fauna. With oats, however, rabbits eat considerably less and reduction of the present field strength would result in more poisoned bait being consumed by individual rabbits. Therefore more would need to be distributed, and the safety aspect would be relatively unchanged.