EVALUATION OF IOPHENOXIC ACID AND RHODAMINE-B FOR MARKING FERAL FERRETS (MUSTELA-FURO)

The blood marker iophenoxic acid, and the fluorescent dye rhodamine B, were evaluated as means of assessing bait consumption in the ferret, Mustela furo. Iophenoxic acid was elevated above baseline concentratio ns for a minimum of 28 days after dosing, indicating that it is a suit able medium-term marker. Rhodamine B marked ferrets for a maximum of 7 days, and would therefore have limited operational use with feral fer rets. Iophenoxic acid was used in a field trial to assess the effectiv eness of a newly developed baiting strategy for control of wild ferret s. All 21 ferrets captured after field baiting with iophenoxic acid ha d elevated levels of serum iodine, indicating that the newly developed baiting strategy is highly effective for marking ferrets.