Freeze-dried rat did not attract interest of 24 captive stoats in any of 4 matrices more than no lure, but stoats were more likely to enter tunnels with freezedried rat before plain ones, and more likley to re-enter tunnels with fresh dead rat and spend longer inside. Freezedried and “chemical” rat odours (4 volatile substances ID from headspace of real rat and made up from commercially available compounds) presented in PVC stick, lasted longer than casein. Chemicals identified from live rat and purchased to make “chemical rat” cost $8.43 in small quantities whereas freezedried ratsticks contained 0.35 worth of rat. Conclusion: “It is essential to maximise the probability of capturing individual stoats, by developing effective, long-lasting lures” p. 8. Actually 18 of 24 stoats in 1st trial and 14 of 18 in 2nd trial first entered tunnels containing freezedried rat in PVC matrix in preference to tunnel with no lure, and “The lack of statistical significance may simply be a consequence of small sample sizes, and should not override the potential biological significance of the results” p. 9. Chemical rat at least as attractive suggesting process had captured relevant compounds as freezedried rat even though these compounds couldnt be detected from them – maybe freezedried rat gives out a different signal?. Recommends further field trials comparing PVC lures directly with eggs.
|Author||A. Byrom, E. B. Spurr, A. T. Airey, K. M. Borkin, C. E. O'Connor and G. J. Forrester|