Use repellents to reduce cable gnawing
Overall effectiveness category Evidence not assessed
Number of studies: 1
Background information and definitions
Human-wildlife conflict can arise where animals cause damage to equipment or installations. Damage, such as that caused by gophers to underground cables, can represent substantial financial losses (Ramey & McCann 1997). If repellents can reduce or prevent damage to cables, this might reduce incentives for carrying out lethal control of such animals.
Ramey C.A. & McCann G.R. (1997) Evaluating cable resistance to pocket gopher damage-a review. Great Plains Wildlife Damage Control Workshop, 13, 107–113.
Supporting evidence from individual studies
A randomized, replicated, controlled study (year not stated) in a captive facility in Colorado, USA (Shumake et al. 1999) found that repellents only deterred cable gnawing by northern pocket gophers Thomomys talpoides when encased in shrink-tubing. When repellents were contained within shrink-tubing, there were reductions in all four damage measures (mass loss, chewing depth, chewing width and volume of chewed area – see paper for details) for capsaicin-treated cables but just for two of the measures (mass loss and chewing depth) for denatonium benzoate-treated cables, when compared to cables treated with a non-deterrent substance. However, when applied to cables without shrink tubing, there was no reduction in the four damage measures for either capsaicin or denatonium benzoate-treated cables, compared to cables treated with a non-deterrent substance. Gophers were live-trapped in the wild and transferred to individual enclosures in captivity. Enclosures each had a 1.2-cm-diameter coaxial cable across an opening. Cables were sponged with capsaicin (six gophers) or denatonium benzoate (six gophers), each in solution with Indopol®, or with Indopol® alone (three gophers). The same treatments were applied to cables then encased in a shrink-tube coating (which adhered to the cable upon exposure to heat) with six gophers each offered cables treated with capsaicin, denatonium benzoate or Indopol® alone. In each case, after seven days, cables were assessed for weight and volume loss and for depth and width of gnawing damage.Study and other actions tested