Use predator scent to deter crop damage by mammals to reduce human-wildlife conflict
Overall effectiveness category Likely to be beneficial
Number of studies: 3
Background information and definitions
Wild herbivores may be sensitive to scents from predators and may alter their behaviour or visitation rates to a site accordingly (Wikenros et al. 2015). If scents can be deployed artificially, they could reduce crop damage caused by wild herbivores and, hence, reduce motivations for carrying out lethal control of these animals.
Wikenros C., Kuijper D.P.J., Behnke R. & Schmidt K. (2015) Behavioural responses of ungulates to indirect cues of an ambush predator. Behaviour, 152, 1019–1040.
Supporting evidence from individual studies
A replicated, randomized, controlled study (year not stated) on captive animals from Washington State, USA (Epple et al. 1995) found that coyote Canis latrans urine was more effective at deterring food consumption by mountain beavers Aplodontia rufa than were four synthetic compounds. In two-choice feeding trials, the quantity of coyote urine-soaked food removed by male beavers (7 g) was lower than that of water-soaked food removed (14 g). The same pattern held for females (coyote urine: 1 g; water: 7 g). A3-Isopentenyl methyl sulfide (IMS) did not affect food choice when compared to an untreated “blank” (IMS: 8–11 g; blank: 7 g), nor did 2,2-dimethylthietane (DMT) (DMT: 7–13 g; blank: 10–14 g). A mix of 2-propylthietane and 3-propyl-l,2-dithiolane (PT/PDT) reduced food retrieval (PT/PDT: 14 g; blank: 18 g) but the response was not apparent during longer (5 day) exposure (PT/PDT: 31 g; blank: 35 g). Twelve wild-caught mountain beavers (six male and six female) were held in captivity for several months prior to the experiment. Trials were run as choice tests between bowls 25 cm apart. Food remaining after one or two hours was weighed. Each beaver was used twice for each choice experiment.Study and other actions tested
A replicated, randomized, controlled, before-and-after study in 2000–2001 in a forest in Ohio, USA (Seamans et al. 2002) found that coyote Canis latrans hair reduced feeding at troughs by white-tailed deer Odocoileus virginianus. With one bag of coyote hair/trough, deer consumed less corn (103 kg) than before bag placement (246 kg). With three bags of coyote hair/trough, deer consumed less corn (46–108 kg/week) than in the week before bag placement (323 kg). At control toughs with empty bags, operated concurrently to experimental troughs, consumption (284–425 kg/week) did not differ to that in the week before bag placement (247–265 kg/week). Ten troughs (≥1 km apart) were fenced on three sides and stocked with whole kernel corn. Five were treatment troughs and five were controls. Stage I (January–February 2000) entailed one week with unprotected troughs. The following week, a nylon mesh bag containing 17 g of coyote hair was placed touching the back of treatment troughs. An empty bag was placed at control troughs. Stage II (January–March 2001) had a similar pre-treatment week, then five weeks with three bags, each containing 16 g of coyote hair, in front of each treatment trough. Three empty bags were placed at each control trough.Study and other actions tested
A replicated, randomized, controlled, before-and-after study in 2000 in a forest in Ohio, USA (Seamans et al. 2002) found that hanging bags of coyote Canis latrans hair did not reduce use of established trails by white-tailed deer Odocoileus virginianus. The number of deer using treatment trails did not differ significantly before (2.6 deer/day) or after (3.1 deer/day) placement of coyote hair bags. Similarly, the number of deer using non-treatment trails was not significantly different before (3.4 deer/day) or after (5.1 deer/day) placement of empty bags. Deer passes along 10 active trails (around 1 km apart) were recorded for three weeks (18 August to 8 September 2000) using infra-red monitors. A nylon mesh bag containing 16 g of coyote hair, was then suspended 2 m high from a tree along five randomly selected trails. Empty bags were hung at the other five trails. Monitoring continued for three further weeks (8–29 September 2000).Study and other actions tested