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We estimated bobcat (Lynx rufus) density for 3 different locations in northern California using active infrared-triggered cameras. Using differences in pelage pattern as well as other physical characteristics, we identified individual bobcats from photographs, and used mark-recapture techniques to estimate population density. Camera density affected the precision of population estimates. The same population was estimated using camera densities of 0.5, 1, 2, 4, 6, and 8 cameras ⋅ km-2. Higher camera densities resulted in more captures and recaptures of bobcats and, conse- quently, in more precise density estimates. Similarly, the number of photo-captures and recaptures increased with increasing study duration. Increasing the area sampled resulted in the capture of more individuals but did not increase the percentage of recaptures. While some locations captured multiple bobcat photographs (e.g., 15 at 1 station), these photos tended to be recaptures of the same individual. There were no more than 2 individuals photo-captured at any 1 camera location. Bobcat density varied among habitat types as predicted. We estimated density as 0.27 bobcats ⋅ km-2 (s = 0.16) overall in an area in the northern Sacramento River Valley and as 0.35 bobcats ⋅ km-2 (s = 0.56) in a steep and rocky canyon within the area. At a 3rd site in the Coast Range, the estimate was 0.39 bobcats ⋅ km-2 (s = 1.44). Bobcats were more diurnal where human activity was less common. In addition, photo-capture was significantly higher along roads and trails without an attractant than it was off-trail with an attractant.

Remote cameras are an increasingly important tool in management and wildlife studies. However, we often do not know if they provide an unbiased sample of populations. Using a marked, radiocollared population of coyotes (Canis latrans) of known social status, we evaluated the influence of temporal (daily and seasonal) and spatial (distance between units, habitat, and proximity to human structures) factors on vulnerability to photo-captures. During 8 unbaited camera sessions of 6 weeks each, we obtained 158 coyote photographs at a photo-capture success rate of 1.6%. We were able to identify not only marked individuals, but also a number of uncollared adults through variation in their pelage. Photo-capture of adults peaked 2 weeks after we established camera stations. Annual success for photographing adult coyotes was greatest during March and April, which corresponded with the dispersal season. The majority of photo-captures occurred at night, and adult photo-captures peaked around midnight, with s...

Golden jackals are locally common in Bangladesh despite intensive cultivation and high human densities. We studied the relative importance of seasonal flooding, rodent prey-base, and daytime cover on the occurrence of golden jackals in the two major agro-ecosystems in Bangladesh, one with annual monsoon flooding and the other without. Jackals were less common throughout the year where floodwaters occurred that would have excluded them for 1–3 months during their pup-rearing season. Diets of jackals were similar in the two agro-ecosystems. Rodents were the most common food type in scats throughout the year. The occurrence of burrowing rats in scats peaked seasonally when these rats were most concentrated in ripening cereals, suggesting that jackals are beneficial for rat control. Radiotelemetry of seven jackals in the non-flooded agro-ecosystem over an 11-month period indicated that sugarcane was the preferred type of daytime cover, despite representing only 2–4% of the area. There was a day-to-day return rate of 67% to the same 1-ha patch of cover. Evidently, sugarcane provides daytime cover for avoiding humans and for feeding on roof rats (Rattus rattus), which concentrate in this crop. Evidence suggests that breeding pairs of jackals were annual residents that defended cover (average of 37.3 ha) but not foraging areas beyond.

Resolving conflicts between predators and livestock producers depends on obtaining reliable information about the predators that kill livestock. We used salivary DNA obtained from attack wounds on domestic sheep carcasses to identify the species of predator responsible for the kill, as well as the sex and individual identity of coyotes (Canis latrans) that killed sheep. Coyotes killed 36 of 37 depredated sheep. Breeding pairs whose territories overlapped sheep grazing areas were the primary predators on domestic sheep, and only breeding pairs killed multiple sheep. Breeding males, acting alone or with their mate, were involved in 21 of 25 kills. Breeding females participated in 13 kills, but only 1 breeding female killed sheep on her own. Transient females did not kill sheep, and both kills by transient males occurred in territories with a breeding vacancy. Our results suggest that predator control should be targeted at breeding male coyotes. Salivary DNA is a potentially powerful means of both investigating predation patterns and evaluating the effectiveness of control at targeting individuals that kill livestock.

This paper examines the severity of livestock depredation by coyotes (Canis latrans), reviews evidence implicating breeding (or “alpha”) coyotes in the majority of incidents, evaluates currently used depredation control techniques, and suggests directions for future research. Nonlethal control ranges from varied animal husbandry practices to coyote behavioral modification or sterilization. These methods show significant promise but have not been proven effective in controlled experiments. Therefore, many livestock producers rely on lethal control, and most employ nonselective strategies aimed at local population reduction. Sometimes this approach is effective; other times it is not. This strategy can fail because the alpha coyotes, most likely to kill livestock, are the most resistant to nonselective removal techniques. An alternative is selective lethal control. Livestock Protection Collars (LPCs) and coyote calling are the primary selective lethal approaches. However, LPCs do not have support from the general public due to the toxicant used, and the factors affecting the selectivity of coyote calling have not been studied. The greatest impediments to effective coyote depredation management currently are a scarcity of selective control methods, our lack of understanding of the details of coyote behavioral ecology relative to livestock depredation and wild prey abundance, the absence of solid research examining the effectiveness of different control techniques in a variety of habitats and at multiple predation intensities, and the dearth of rigorous controlled experiments analyzing the operational efficacy of selective removal versus population reduction.

The primary objective of this study was to develop a better understanding of coyote (Canis latrans) wariness particularly as it related to social status. We determined that territory status (controlling alpha, resident beta, or nonterritorial transient) affected vulnerability to photo-capture by infrared-triggered camera systems. All coyotes were wary of cameras, leading to relatively low numbers of photo-captures, most of which occurred at night. Alphas were significantly underrepresented in photographs and were never photo-captured inside their own territories. Betas were photographed inside and outside their territories, whereas transients were most often photographed on edges of territories. Both alphas and betas were photographed more often on territorial edges when outside their territories. We next addressed the question of how alphas were better able to avoid photo-capture. Alphas tracked human activity within their territories and presumably learned the locations of cameras as they were being set up. They did this either by approaching our location directly or by moving to a vantage point from where they could observe us. Betas and transients either withdrew or did not respond to human activity. Trials in which a dog was present were more likely to elicit an approach response from alphas. Avoidance of camera stations and the tracking of human activity implied wariness toward objects or locations resulting from their learned association with human presence rather than neophobia toward the objects themselves.

Research at the UC Hopland Research and Extension Center (HREC) has improved our understanding of how to reduce sheep depredation while minimizing the impact on coyotes. Analysis of a 14-year data set of HREC coyote-control efforts found that sheep depredation losses were not correlated with the number of coyotes removed in any of three time scales analyzed (yearly, seasonally and monthly) during corresponding intervals for the next 2 years. Field research using radiotelemetry to track coyotes supported and explained this finding. For example, in 1995, dominant “alphas” from four territories were associated with 89% of 74 coyote-killed lambs; “betas” and transients were not associated with any of these kills. Relatively few coyotes were killing sheep, and these animals were difficult to capture by conventional methods at the time of year when depredation was highest. However, selective removal of only the problem alpha coyotes effectively reduced losses at HREC.

I describe the management of populations of the red-billed quelea (Quelea quelea) in eastern Africa for the purpose of protecting ripening cereals. The management strategy is to remove selectively only those quelea aggregations likely to come in contact with concentrations of vulnerable cereal. The opportunities for selective targeting vary among populations. Two models are presented here describing different quelea populations. The first is a general model to illustrate the relationship between migration, nesting, and damage. The second model describes the quelea population in the Ethiopian Rift Valley and the selective targeting of nesting colony groups for reducing damage to lowland sorghum in the Awash River Basin.

We evaluated the effect on sheep losses of selectively removing breeding coyotes (Canis latrans) from territories experiencing depredations. Breeding pairs of coyotes were the primary predators of sheep, and they killed sheep only within or on the periphery of their territories. Removal of either or both members of a breeding pair reduced or eliminated predation in that territory during the subsequent 3-month period. Killing of sheep by coyotes d sooner in territories that overlapped lambing pastures than in those that did not. For territories with access to lambs, the average time interval until killing of lambs resumed (43 days) approximated the time for a replacement pair of coyotes to become established. Removals of breeding coyotes during the nonlambing season did not reduce losses during the following lambing season. Although

Predation by coyotes (Canis latrans) on livestock continues to plague producers in the United States. Agricultural interests are concerned about coyote predation because sheep inventories in the U.S.have declined >85% in the past 60 years, with a 25% decline between 1991 and 1996. This decline in sheep numbers has been attributed to low economic returns among producers, with coyote predation cited as a major causative factor. Generalizations about the magnitude and nature of depredations can be misleading because of the varied nature of sheep operations, including size of operations, differences in management, and environmental circumstances surrounding individual operations. Coyote depredation rates appear to be influenced by sheep management practices, coyote biology and behavior, environmental factors, and depredation management programs. Most nonlethal depredation control techniques fall within the operational purview of the producers. The major controversy regarding depredation management focuses on programs that remove coyotes to prevent or curtail predation on domestic stock, especially on public lands. Differences in the magnitude, nature, and history of problems caused by coyotes, as well as the circumstances in which they occur, dictates a need for a variety of techniques and programs to resolve problems. The resolution of coyote depredation upon livestock remains controversial for producers, resource managers, and the general public. Because various segments of society attach different values to coyotes, resolution of depredations should use management programs that integrate the social, legal, economic, and biological aspects of the animals and the problem. Preferred solutions should involve procedures that solve problems as effectively, efficiently, and economically as possible in the least intrusive and most benign ways. Predation management requires a partnership among producers and wildlife managers to tailor programs to specific damage situations so the most appropriate techniques can be selected. This paper attempts to clarify the issues surrounding depredation management, synthesize past and current research, and provide information to resource managers associated with coyote depredation management. This synthesis integrates current understandings of coyote biology and behavior, the nature of depredations upon sheep producing enterprises, and the merits of various depredation control strategies and techniques.

Stable URL:http://links.jstor.org/sici?sici=0022-541X%28199907%2963%3A3%3C939%3ARVOCTR%3E2.0.CO%3B2-LThe Journal of Wildlife Management is currently published by Alliance Communications Group.Your use of the JSTOR archive indicates your acceptance of JSTOR's Terms and Conditions of Use, available athttp://www.jstor.org/about/terms.html. JSTOR's Terms and Conditions of Use provides, in part, that unless you have obtainedprior permission, you may not download an entire issue of a journal or multiple copies of articles, and you may use content inthe JSTOR archive only for your personal, non-commercial use.Please contact the publisher regarding any further use of this work. Publisher contact information may be obtained athttp://www.jstor.org/journals/acg.html.Each copy of any part of a JSTOR transmission must contain the same copyright notice that appears on the screen or printedpage of such transmission.The JSTOR Archive is a trusted digital repository providing for long-term preservation and access to leading academicjournals and scholarly literature from around the world. The Archive is supported by libraries, scholarly societies, publishers,and foundations. It is an initiative of JSTOR, a not-for-profit organization with a mission to help the scholarly community takeadvantage of advances in technology. For more information regarding JSTOR, please contact support@jstor.org.http://www.jstor.orgFri Oct 26 13:06:05 2007

Coyote (Cauis latrans) depredation is a chronic problem for sheep producers in the western United States. Due to increasingly localized control efforts, behavior of individual coyotes in sheep-ranching environments is becoming a more important consideration. We radiotracked 14 coyotes on a year-round sheep-ranching facility in north-coastal California during September 1993-December 1995. Breeding coyote pairs used mutually exclusive territories (maximum overlap between 90% adaptive kernel home ranges = 4%). Nonbreeding coyotes were transient or varied in their degree of fidelity to putative natal territories but generally avoided cores of nonnatal territories. Breeding coyotes whose territories contained sheep were the principal predators of sheep. In the 1994 lambing period (1 Jan-31 May). radiotelemetry indicated that 1 breeding male was responsible for 71% of 65 kills. In the 1995 lambing period, 4 breeding pairs were strongly implicated in 92% of 48 kills and were suspected of 85% of 26 additional kills; nonbreeders were not associated with sheep depredation. Depredation was reduced only when territorial breeders known to kill sheep were removed. These results suggest the need for management to target breeding adults in the immediate vicinity of depredation. Efforts to remove individuals > 1 territory-width away from problem sites are unlikely to reduce depredation and may exacerbate the problem by creating vacancies for new breeders that might kill sheep.

je in\.estigated predation on lambs by bobcats (Lynr mfusi relative to coyotes car ti.^ lntrcit~s) horn J~ine 1994 through November 1995 at Hopland Kesearcli and Extension Center (HREC) in north-coastal C;alifornia, where both predators occur at equally high densities. Larnh losses during this study were t)pical for HKEC and surrounding ranches and inciuded 64 (5.3% of lambs pastured) confirmed predator kills and 134 (11.18)missing individuals. Fift>-seven of the preciator-killed lambs were attribi~ted to coyotes, whereas none were assigned to bobcats. The proportion of bobcat scats containing sheep remains was small i4.2%), and occurrence did not peak in the lambing season, suggesting that sheep consumed by bobcats were scav- enged Sheep were co~nrnon in colote scats (21.4%) and occnrred most freqr~entlv in scats from the ulnter- - . sphng lambkg season. Coyotes were responsible for all lamb kills in intensi~rely monitored pastures for which predator species could be identified. Use of space by radiocollared bobcats was not noticeably influenced by the presence of lambs. \Ve concluded that bobcats were not important predators of lambs at HKEC and not the cause for the relatively large nuirlbers of lambs missing and unaccounted for each year.

Responses of golden jackals ( Canis aureus ) to broadcasted howling were investigated in rural Bangladesh. Two hypotheses were tested: that the howl response shows the same annual trends reported for other Canis , being high during the season of pairing-mating when territories are being established, and low during the denning season when there is a risk to vulnerable young from advertising the location of their den to rival conspecifics; that the frequency of approach responses (confrontation) varies inversely with howl responses and is higher during denning when howling is low. Results support both hypotheses and are consistent with the primary function of howling being as a passive means of territory maintenance whereby dominant animals advertise their locations to facilitate mutual avoidance between groups and thereby reduce accidental confrontation.

Coyotes (Canis latrans) are a major predator of domestic sheep (Ovis aries) grazed on open range, but studies have not examined how coyote movement patterns change in relation to this temporally intermittent and spatially clumped food resource. Using 8 resident coyotes in the Sagehen Creek watershed, Nevada County, California, we found that coyote core areas (64% adaptive kernal estimator) overlapped more while sheep were in the basin, that at least 1 resident animal followed the sheep into other animals' core areas, and that coyotes did not avoid each other in areas where sheep were concentrated. We conclude that under the conditions of our study, territoriality in coyotes does not limit coyote access to sheep. Conclusions drawn by studies of coyotes not influenced by sheep may be spurious if inferences are made to sheep-influenced populations.