U.S. Department of Agriculture: Animal and Plant Health Inspection Service


Date of this Version



Published in Wildlife Society Bulletin 2000, 28(1):76-83.


Foraging by forest mammals can be significantly detrimental to reforestation efforts. Repellents may offer a nonlethal solution for some situations. Hot Sauce® animal repellent uses capsaicin, a trigeminal irritant that should be aversive to most mammals. We conducted a series of tests evaluating the impact of Hot Sauce on foraging by 5 species of forest mammals. In our first study, we examined its potential to reduce browsing by black-tailed deer (Odocoileus hemionus). Damage to Western redcedar seedlings (Thuja plicata) was initially reduced with application of a 6.2% Hot Sauce solution, but efficacy began to decline after 2 weeks. Big Game Repellent Powder® reduced deer damage to redcedar for the entire 6-week study (F≥ 143.9, P≤0.01). Two-choice pen tests evaluated 0.06, 0.62, 3.1, and 6.2% Hot Sauce solutions as a repellent for pocket gopher (Thomomys mazama), porcupine (Erethizon dorsatum), and mountain beaver (Aplodontia rufa). Mountain beavers were not repelled by any concentration of Hot Sauce (F≥1.94, P≤0.18). Pocket gophers were repelled moderately by the 0.62, 3.1, and 6.2% concentrations, but even the 6.2% solution rarely reduced consumption below 50% of the food available. Porcupine foraging was reduced >48% by all repellent concentrations (F≥ 7.08, P≤0.04). Beavers (Castor Canadensis) were not repelled consistently by Hot Sauce in multiple-choice tests of the 0.06, 0.62, and 6.2% solutions. Although Hot Sauce effectively repelled some species, at a cost of $12.25/gallon for the 6.2% repellent solution, it may not be cost-effective for most situations. Additionally, our data indicate there may be difficulties with product durability under field conditions.