Coyotes can be a significant concern for sheep producers
(Photo: California Agriculture)
Conflicts between livestock and predators are perhaps inevitable, especially on extensively managed rangelands (Breck 2004). In many parts of North America, large carnivore populations are increasing due to habitat restoration, reintroduction, and legal protection efforts. In many cases, these single-species conservation successes have increased human-carnivore conflicts and highlighted concerns about ‘whole picture’ tradeoffs across multiple-use, working landscapes. Public perception and legal restriction of lethal predator control makes knowledge and use of nonlethal livestock protection methods critical for California ranchers. Reducing conflicts between predators and livestock is critical for maintaining both viable ecosystems and ranching enterprises (Miller et al. 2016). This publication will help producers evaluate the types of livestock protection tools that may fit their site-specific needs. We should note that much of the research on nonlethal livestock protection tools has been conducted outside California. In addition, experimental studies (as opposed to surveys) regarding the efficacy of nonlethal tools are rare (Eklund et al. 2017). Future research may adapt these tools to California-specific conditions and predators.
A range rider monitoring cattle and wolf activity in Wallowa County. More information. (Photo: Diana Hunter)
In addition to providing forage for livestock, California wildlands provide habitat for mountain lions (Photo: CDFW)
Gray wolves have returned to California (Photo: CDFW)
Predator Impacts
The killing of livestock by predators represents a direct economic loss to ranchers. These direct losses can be quantified using current market prices; however, indirect losses pose greater complexity in assessing the total cost of predator impacts to ranchers. Current research suggests that indirect losses (such as reduced weight gain, reduced reproductive success, and additional labor) may be more substantial than direct predator losses (Ramler et al. 2014). In addition, the loss of an individual animal also represents the loss of that animal’s future genetic potential in a particular herd or flock, as well as the loss of years of investment by the rancher (Naughton-Treves et al. 2003).
Livestock depredation is an emotional issue for ranchers, intertwined with their sense of stewardship and responsible animal husbandry. On the other hand, lethal control of predators is often a contentious issue for the public. While cattle death losses from predators are generally less than losses from other sources (including disease and old age), localized predator impacts can be severe. Not surprisingly, sheep producers typically experience greater impacts from predation. While just 1% of reported death losses of mature cattle in California in 2015 were attributed to predators, 19% of reported death losses in mature sheep in 2014 were caused by predators (Table 1). Similarly, while approximately 6% of reported calf losses in 2015 were due to predators, over 45% of lamb losses were predator-caused.
Table 1: Death losses by cause for cattle and sheep in California (USDA-APHIS)
Non-Lethal Protection methods
USDA-APHIS found only 20 percent of U.S. beef cattle operations used nonlethal predator protection tools in 2015 (USDA-APHIS 2016). Small ruminant producers, who generally face greater predation risks than beef producers, make greater use of these tools – in 2014, 58% and 93% of sheep and goat operations, respectively, used one or more nonlethal tools (USDA-APHIS 2014). Table 2 summarizes types and combinations of tools used by beef cattle, sheep, and goat producers.
Table 2: Nonlethal livestock protection tools used by ranchers (USDA-APHIS)
Success of nonlethal protection tools may be measured on a gradient from reduction to total elimination of predation. Most of the current information on nonlethal tools has been conducted via producer surveys, with limited published experimental data. While Eklund et al. (2017) and others have focused on analyzing peer-reviewed literature, we have included observations and analysis from scientific studies as well as credible, on-the-ground experience. Therefore, Table 3 combines existing experimental research with field-based information (including Shivik 2004; Bangs et al. 2006; Eklund et al. 2017; Stone et al. 2017). This table is intended to assist producers in evaluating a suite of nonlethal tools that may fit their particular operations. Site-specific conditions (like topography, vegetative cover, and other factors) should also be considered.
Table 3: Tool selection guidelines
Effective livestock guardian dogs bond with the livestock they are protecting (Photo: Dan Macon)
Livestock Guardian Dogs
Livestock guardian dog breeds were developed through selective breeding in Europe and Asia to protect livestock from bears and wolves (Andelt 2004). Common breeds in North America include Great Pyrenees (originally from France), Anatolian Shepherd and Akbash (from Turkey), Komondor (from Hungary), and Maremma (from Italy) (USDA-APHIS 2010). Due to increased predation from gray wolves and grizzly bears in the Northern Rocky Mountains, USDA Wildlife Services is currently investigating additional breeds—including Kangal (from Turkey), Karakachan (from Bulgaria), and Cao de Gado Transmontano (from Portugal)—for protective capabilities and docility towards humans (USDA-APHIS 2014). Several studies suggest that livestock guardian dogs lower the risk of sheep predation (Eklund et al. 2017).
Livestock guardian dogs disrupt predatory behavior rather than displace predators, such that predators likely remain present and continue to prey on other wildlife species. While further study is necessary, this suggests that guardian dog use does not result in increased predator pressure on neighboring operations that do not use dogs (Coppinger et al. 1988). Livestock protection behaviors must be induced or enhanced at some level by appropriate rearing conditions, training, and management. Proper rearing of livestock guardian dog puppies is critical; improperly reared dogs cannot be retrained to become successful guardians. Similarly, dogs that come from working (as opposed to pet) lines generally make better guardians. Producers should utilize the natural genetic and behavioral variations in these dogs to match conditions. For example, more athletic and aggressive dogs may be more appropriate where the predators are similarly athletic and aggressive (Coppinger et al. 1988).
Compared with other nonlethal tools (described below), livestock guardian dogs seem to be the most effective across all operation sizes (Gehring et al. 2010). Livestock guardian dogs have been found to increase range of foraging, foraging efficiency, and forage consumption by sheep with previous familiarity with guardian dogs (Webber et al. 2015). Dogs can be bonded with cattle (and other livestock) as well, and have been shown to reduce wolf and coyote visitations in pasture settings (Gehring et al. 2010). Additionally, in a survey of 150 Australian producers, 66% reported no predations and 30% reported decreased predations after introducing livestock guardian dogs to their operations (VanBommel and Johnson 2012). These results were consistent across production scales (7.5 acres to over 300,000 acres) and livestock types (primarily cattle and sheep).
Livestock guardian dogs can create problems. They can be aggressive toward people, harass non-target wildlife or livestock (potentially causing injury or death), injure herding dogs, or destroy property. Livestock guardian dogs are more prone to illness, injury, and premature death than donkeys or llamas. They may roam beyond ranch boundaries causing problems with neighbors; interfere with livestock herding and/or herd dogs; and affect the use of other predator control methods (like traps and snares) (Braithwait 1996). Livestock guardian dogs acquired as puppies require additional expense and management to be developed into effective working dogs; not every puppy will be successful. Most problems are related to the genetic background of individual dogs, as well as inappropriate rearing and/or management techniques (Coppinger et al. 1988). For livestock guardian dogs to be effective in rangeland cattle operations, producers may need to make significant management and production changes (for example, manage cattle in tighter groups, much like sheep).
Donkeys may be effective guardians in open pasture settings (Photo: R. Dawe)
Donkeys
Some ranchers prefer donkeys to livestock guardian dogs due to their relatively low acquisition and maintenance costs, their compatibility with other predator control methods (e.g., traps, poisons, and snares), their greater longevity, and the fact that they are less likely to stray outside fencelines (Walton and Field 1989). When confronting a predator, an effective donkey will bray, bare its teeth, run towards or chase the predator, and possibly kick or bite (Andelt 2004). Donkeys can effectively deter dogs, coyotes, and foxes (Wilbanks 1995). Previous work indicates that donkeys are most effective when used in relatively open pastures less than 600 acres in size, with fewer than 400 head of sheep or goats (Walton and Field 1989; Andelt 2004). Standard or mammoth donkeys work best. Donkeys should be bonded with livestock for 4-6 weeks before being turned out; bonding is most effective when donkeys are 3-6 months of age. A single jenny (female) or gelded jack (male) appears to be most effective. Donkeys should be raised away from ranch dogs, and dogs should not be used to gather or move livestock. Donkeys can be tested with dogs to determine aggressiveness toward canine predators (Wilbanks 1995).
Donkeys are not effective in large pastures or extensive rangeland settings (Andelt 2004). Additionally, they are not as effective as dogs in guarding against wolves, bears, or mountain lions (Wilbanks 1995). Intact males may be overly aggressive towards livestock, and females in heat may be aggressive towards lambs or kids. Donkeys should be removed from livestock during lambing or kidding because they may disrupt maternal bonding. Donkeys will also bond with other donkeys and equines in adjacent pastures, rather than with the target livestock. Donkeys must not be given access to feeds with ruminant-only feed additives (like Rumensin and other ionophores), which are extremely toxic to all equines (Walton and Field 1989). Additionally, donkeys cannot digest woody forage and therefore require alternative feed sources or supplemental feeding if they are guarding sheep or goats in brush control projects.
llamas can provide protection in smaller scale settings. Since llamas and donkeys share dietary requirements with the livestock they protect, operating costs (including labor) may be lower than for livestock guardian dogs (Photo: C. McDonald)
Llamas
Llamas are South American camelids (a family that includes the domesticated alpaca and the wild guanaco and vicuna). The wild members of the camelid family will chase foxes and flee from mountain lions (Franklin and Powell 2006); similarly, some llamas are naturally aggressive towards dogs and coyotes (Andelt 2004). Typical guarding behaviors include alertness; alarm calling; walking or running toward a predator; chasing, kicking or pawing at a predator; spitting; herding livestock away from a predator; or placing themselves between livestock and a predator. Like donkeys, llamas have similar dietary and management requirements to the livestock they protect. Leadership, alertness, and weight seem to be correlated with aggressiveness. In other words, large and alert llamas make the best guardians (Cavalcanti and Knowlton 1998).
While the research on llamas as livestock guardians is somewhat limited, some literature suggests that llamas can effectively deter dogs, coyotes, and foxes, but not wolves, bears, or mountain lions (Wilbanks 1995). Llamas seem to work best in small- to mid-sized operations (for example, 250-300 sheep or goats in pastures of 250-300 acres). Llamas apparently do not require training to stay with sheep, and single llamas seem to work better than multiple llamas (i.e., they may bond to each other rather than to the livestock they are guarding) (Franklin and Powell 2006).
Electro-net fencing can be highly effective at protecting livestock from feral dogs, coyotes, and other small-to mid-size canine predators (Photo: Dan Macon)
Permanent hard-wire fencing (physical barrier): Conventional 5- or 6-strand barbed wire fences may be effective at containing some livestock (cattle in particular) but are not effective predator barriers. Many producers use permanent steel-wire net fences, augmented by barbed or electrified wires above the net fencing, and occasionally by an electrified trip wire just above ground level on the outside of the net fencing. An adult coyote can squeeze through a 4-by-6 inch opening in woven wire, and can climb or jump fences that are less than 66 inches in height (Thompson 1976). To be a more effective predator deterrent, therefore, conventional woven wire fencing should have electrified top and trip wires (Gates et al. 1978; Acorn and Dorrance 1994).
Permanent electric fencing (psychological and/or physical barrier): Researchers have evaluated a number of configurations of permanent electric fencing. Research from the late 1970s indicates that a 12-wire fence with alternating grounded and electrified wires and an offset electrified trip wire on the outside of the fence is “coyote proof” (Gates et al. 1978). Maintenance of permanent electric fences is the key to continued effectiveness (Wade 1982). Dry soil conditions (combined with improper fence installation), grounding of the fence on vegetation or on itself, and poor construction (especially the fence grounding system) contribute to the failure of electric fences (permanent and temporary alike).
Temporary electric fencing (psychological and/or physical barrier): Temporary electric fences are increasingly utilized to control grazing on crop residues and rented, unfenced land (Ontario Ministry of Agriculture 2016). In some cases, these fences may be effective at protecting livestock from predators as well. Temporary electric fences consist of one or more strands of poly-wire or tape woven with steel wire for electrical conductivity. Several manufacturers make an electrified netting fence (36-48 inches height) in which the horizontal poly-wires may be electrified or alternating hot and grounded. While temporary electric fencing systems typically have a shorter expected life (5 to 7 years) compared to permanent fencing (Ontario Ministry of Agriculture 2016), the initial capital cost is significantly lower. These fences can be energized with portable, battery-powered (and solar charged) low-impedance energizers that deliver a powerful shock (as high as 10 kV). Temporary fences can be configured similarly to the high-tensile electric fences described above to provide predator protection. More frequently, producers utilize electrified netting for predator protection (especially for sheep and goats). Electrified netting has been shown to reduce coyote intrusions from 47% to 6% (Matchett et al. 2013).
Fladry and Turbo (electrified) Fladry (psychological barrier): Fladry is a series of cloth or plastic flags attached to a rope or wire that creates a novel visual stimulus wolves find uniquely frightening (Bangs et al. 2006). Studies in several regions have reported fladry deters wolves (Musiani et al. 2003; Davidson-Nelson and Gehring 2010); however, over time, wolves have been found to become habituated to fladry, willingly crossing fladry barriers to kill livestock (Musiani et al. 2003). Musiani et al. also found that fladry may push wolves to neighboring ranches or unprotected pastures. Turbo fladry (electrified with a standard electric fence energizer) may be as much as 2 to 10 times more effective than non-electrified barriers (Lance et al. 2010). However, hunger increases the likelihood that a wolf will test any fladry barrier. New designs that reduce or eliminate coiling of flags improve effectiveness and reduce maintenance (Young et al. 2015a). Fladry may be a useful tool in smaller-scale pasture settings (e.g., heifer calving pastures or sheep bedding grounds), but are not particularly useful or effective on large-scale grazing allotments (Parks 2015). Fladry may not be an effective deterrent for predators other than wolves (Davidson-Nelson and Gehring 2010), although one study has suggested fladry may deter coyotes as well (Young et al. 2015a).
Human Presence and Stockmanship
Range riders can increase the efficacy of other nonlethal tools (by facilitating timely carcass removal and increased human presence on rangelands (Photo: Dan Macon)
In some situations, human presence has been shown to deter predation. Additionally, active hazing with less-than-lethal munitions may modify carnivore hunting patterns and dietary preferences (Bangs et al. 2006). We should note that in California, the use of less-than-lethal munitions on some species (notably wolves) is not permitted. Many large-scale open range sheep and goat operations in the Western U.S. utilize herders to manage their day-to-day grazing operations. These herders are typically on site with flocks 24 hours per day, 7 days per week. In 2014, 34% of large-scale sheep operations (>1,000 head) that used nonlethal tools reported using herders (USDA-APHIS 2015). Within all sheep operations, just over 6% used herders (see Table 2). More than half of the large-scale sheep producers who use herders indicated they checked sheep more frequently when they were in high predation areas or seasons (USDA-APHIS 2015). Nearly one-third of U.S. sheep production is managed using guest worker (H-2A) herders, most of whom come from Peru or Bolivia; therefore, changes in U.S. immigration policy may affect access to herders (American Sheep Industry Association 2015).
Individual ranchers, rancher associations, or nonprofit organizations may employ range riders. Range riders have mostly been deployed in areas with potential wolf-livestock conflicts, often with the specific task of disrupting predatory behavior. It has been suggested that low-stress stockmanship techniques can re-instill herd instinct in cattle. While there is little empirical evidence regarding effectiveness, ranchers perceive the benefits of range rider programs to include depredation mitigation, increased management and information on livestock, rapid carcass identification, and a variety of social benefits (including reduced stress, reduced trespass and littering, improved public perception, and trust building). Range riders can also provide additional tools beyond simply being present on the landscape, including carcass removal, treatment of injured or sick animals, and stockmanship (Parks 2015). Wolves, especially, may become habituated to seeing humans, avoiding areas where they see humans during daylight hours and returning at night (Parks 2015; Williams personal communication 2016). Varying the pattern of human presence appears to be critical to preventing habituation. Finally, range rider programs may be cost-prohibitive in the long term. Most existing range rider programs are funded through combination of grant funding (from nonprofit organizations and/or government agencies) and in-kind contributions from ranchers (e.g., housing, horses or ATVs, investment of time, etc.). Ranchers who have participated in range rider programs in the northern Rocky Mountains perceive the costs to outweigh the benefits (Parks and Messmer 2016).
Fright Tactics and Devices
Fladry and turbo-fladry (which is electrified) may provide protection from gray wolves. Fladry is typically used in specific settings, like calving pastures or sheep bedding grounds (Photo: J. Williams)
Some predators are afraid of novel stimuli. Strobe lights, propane cannons, and siren devices (including radio- and motion-activated guard devices) may temporarily displace or confuse predators (Bangs et al. 2006). Early research into battery operated strobe/siren devices in fenced-pasture sheep operations across the western US found these devices deterred coyotes for up to 91 days and reduced lamb losses an estimated 44-95% (Linhart 1984; Linhart et al. 1992). However, habituation can be a problem if these devices are randomly—rather than behaviorally—activated (Shivik and Martin 2001). On the other hand, preliminary research at the University of California Hopland Research and Extension Center (Mendocino County) indicated mixed results with a new type of strobe light that emits random patterns of flashing light (trademarked as FoxLights™). While initial results suggest FoxLights™ may be effective in deterring fox predation, the data does not support hypotheses of reduced livestock predation by coyotes, black bears, or mountain lions (McInturff et al. 2016).