William F. Andelt

Variation in coyote diets associated with season and successional changes in vegetation

Diets of coyotes (Canis latrans) on the Rob and Bessie Welder Wildlife Refuge (WWR) in south Texas were determined from analyses of scats collected during 1961-62, 1973-74, 1975-76, and 1978-79. Diets varied among years due to successional changes in vegetation and changes in prey abundance. Coyote diets also varied seasonally, reflecting changing abundances of a wide variety of food items, differential vulnerability of prey, effects of plant phenology, and weather conditions. J. WILDL. MANAGE. 5 1(2):273-277 Short-term studies have shown pronounced seasonal variation in coyote diets related to the availability of various foods (Gipson and Sealander 1976, Litvaitis and Shaw 1980, MacCracken and Hansen 1982, Van Vuren and Thompson 1982, Harrison and Harrison 1984). However, reports of coyote diets over long periods of time from the same area (e.g., Leopold and Krausman 1986) are scarce, and we are not aware of studies reporting variations in diets associated with successional changes in vegetation. In this paper we report on coyote diets on the WWR during 1961-62, 1973-74, 1975-76, and 1978-79, comparing feeding patterns among these periods and relating variations in diets to changes in vegetation and vertebrate prey populations. We thank the Rob and Bessie Welder Wildlife Foundation (WWF), Sinton, Texas and the Natl. Sci. Found. for funding this study. This paper is WWF Contrib. 302.

Relative effectiveness of repellents for reducing mule deer damage

We tested the repellency of chicken eggs, MGK ® Big Game Repellent (BGR), coyote (Canis latrans) urine, thiram, Hinder ®, bars of soap, and Ro.pel ® on tame mule deer (Odocoileus hemionus) in Colorado during May and June 1989. Chicken eggs, GR, and coyote urine performed better than the other repellents for deterring deer from feeding on pelleted rations. Consumption of rations treated with odor repellents increased from Day 1 through Day 4 of the trial, but consumption of thiram-treated rations decreased. The repellency of eggs, BGR, and coyote urine was reduced when apple twigs were sprayed with 7 cm of water to simulate heavy rainfall. When the deer were moderately hungry, even the best performing repellents failed to deter browsing

Effectiveness of capsaicin and bitrex repellents for deterring browsing by captive mule deer

Because mule deer (Odocoileus hemionus) and white-tailed deer (O. virginianus) cause extensive and costly damage to orchards, nurseries, shelterbelts, and ornamental plantings in Colorado, we evaluated 3 concentrations (0.062, 0.62, and 6.2 %) of Hot Sauce Animal Repellent® (Hot Sauce), habanero peppers, Tabasco® sauce, Ani-spray®, and liquid MGK® Big Game Repellent (BGR) as browsing deterrents on tame mule deer from 31 December 1991 to 25 January 1992. While consumption of apple twigs treated with Anispray and the 0.062 % concentration of Hot Sauce did not differ (P > 0.05) from the control (tap water), a 6.2 % concentration of Hot Sauce (100 times the concentration labeled for deer) and BGR reduced (P < 0.05) consumption relative to the control and other repellents

Livestock guard dogs reduce predation on domestic sheep in Colorado.

We surveyed the effectiveness of livestock guard dogs for reducing predation on domestic sheep in Colorado during 1993. The number of producers using dogs increased from about 25 in 1986 to >159 in 1993. The proportion of sheep with dogs increased from about 7% in 1986 to about 68% in 1993. Producers with dogs, compared to producers without dogs, lost smaller proportions of their lambs to predators, especially coyotes ( Canis latrans Say), and smaller proportions of ewes and lambs to black bears (Ursus americanus Pallas) and mountain lions ( Felis concolor L . ) . Overall, producers who did not have guard dogs lost 5.9 and 2.1 times greater proportions of lambs to predators than producers who had dogs in 1986 and 1993, respectively. Proportions of sheep killed by predators decreased with the number of years that producers used guard dogs. Mortalities of ewes to predators regardless of type of operation and lamb mortality on open range decreased more from 1986 to 1993 for producers who obtained dogs between these years compared to producers who did not have dogs. Of 160 producers using dogs, 84% rated their dogs overall predator control performance as excellent or good, 13% as fair, and 3% as poor. More producers (n = 105) indicated effectiveness of their dogs did not change with time, compared to producers (n = 54) indicating effectiveness changed. More producers (n = 35) also indicated their dogs became more effective over time compared to producers (n =19) indicating their dogs became less effective. Estimates provided by 125 producers indicate that their 392 dogs saved

RELATIVE PREFERENCE OF CAPTIVE COW ELK FOR REPELLENT-TREATED DIETS

891,440 of sheep from predation during 1993. A total of 154 of 161 (96%) producers recommend use of guard dogs to other producers.

Adaptive divergence despite strong genetic drift: genomic analysis of the evolutionary mechanisms causing genetic differentiation in the island fox (Urocyon littoralis)

Because of the extent and cost of elk (Cervus elaphus nelsoni) damage in Colorado, we tested the repellency of MGK? Big Game Repellent (BGR), chicken eggs, coyote (Canis latrans) urine, Hinder?, Hot Sauce Animal Repellent? (Hot Sauce), Ro -pel?, and thiram on tame cow elk there from December 1990 to February 1991. At the concentrations used, coyote urine and BGR performed better than the other repellents for deterring elk from feeding on cubed alfalfa hay. Consumption of rations treated with odor repellents (BGR, chicken eggs, coyote urine, and Hinder) increased from day 1 through day 5 of the trial, but consumption of rations treated with thiram (a taste repellent) decreased. In a second trial, hungry elk consumed significantly more repellent-treated apple twigs (Malus domestica) than did elk that were maintained on an ad libitum diet. Hot Sauce, applied at 100 times (6.2%) the labeled concentration for deer (Odocoileus spp.), deterred all 9 satiated elk and 7 of 9 hungry elk from browsing on apple twigs, but the labeled concentration (0.06%) failed to deter most elk fed ad libitum and all elk when hungry. Coyote urine, at 10% and 100% concentrations, failed to deter hungry elk, but the 100% solution moderately deterred elk fed ad libitum from browsing on apple twigs. Thiram applied at the labeled concentration and at 10% of the labeled concentration for deer failed to deter any elk when hungry and most elk when fed ad libitum. In a third trial, Hot Sauce at concentrations of 0.06%, 0.20%, and 0.62% did not deter any of 9 elk fed 50% of their average daily intake, but the 2.0% and 6.2% concentrations deterred 2 and 6 elk, respectively. Hot Sauce, at concentrations of 6.2% and 12.4%, and 100% coyote urine were not phytotoxic to apple trees. Abstract: Because of the extent and cost of elk (Cervus elaphus nelsoni) damage in Colorado, we tested the repellency of MGK? Big Game Repellent (BGR), chicken eggs, coyote (Canis latrans) urine, Hinder?, Hot Sauce Animal Repellent? (Hot Sauce), Ro -pel?, and thiram on tame cow elk there from December 1990 to February 1991. At the concentrations used, coyote urine and BGR performed better than the other repellents for deterring elk from feeding on cubed alfalfa hay. Consumption of rations treated with odor repellents (BGR, chicken eggs, coyote urine, and Hinder) increased from day 1 through day 5 of the trial, but consumption of rations treated with thiram (a taste repellent) decreased. In a second trial, hungry elk consumed significantly more repellent-treated apple twigs (Malus domestica) than did elk that were maintained on an ad libitum diet. Hot Sauce, applied at 100 times (6.2%) the labeled concentration for deer (Odocoileus spp.), deterred all 9 satiated elk and 7 of 9 hungry elk from browsing on apple twigs, but the labeled concentration (0.06%) failed to deter most elk fed ad libitum and all elk when hungry. Coyote urine, at 10% and 100% concentrations, failed to deter hungry elk, but the 100% solution moderately deterred elk fed ad libitum from browsing on apple twigs. Thiram applied at the labeled concentration and at 10% of the labeled concentration for deer failed to deter any elk when hungry and most elk when fed ad libitum. In a third trial, Hot Sauce at concentrations of 0.06%, 0.20%, and 0.62% did not deter any of 9 elk fed 50% of their average daily intake, but the 2.0% and 6.2% concentrations deterred 2 and 6 elk, respectively. Hot Sauce, at concentrations of 6.2% and 12.4%, and 100% coyote urine were not phytotoxic to apple trees.

Effect of Group Size on Survival of Relocated Prairie Dogs

The evolutionary mechanisms generating the tremendous biodiversity of islands have long fascinated evolutionary biologists. Genetic drift and divergent selection are predicted to be strong on islands and both could drive population divergence and speciation. Alternatively, strong genetic drift may preclude adaptation. We conducted a genomic analysis to test the roles of genetic drift and divergent selection in causing genetic differentiation among populations of the island fox (Urocyon littoralis). This species consists of six subspecies, each of which occupies a different California Channel Island. Analysis of 5293 SNP loci generated using Restriction‐site Associated DNA (RAD) sequencing found support for genetic drift as the dominant evolutionary mechanism driving population divergence among island fox populations. In particular, populations had exceptionally low genetic variation, small Ne (range = 2.1–89.7; median = 19.4), and significant genetic signatures of bottlenecks. Moreover, islands with the lowest genetic variation (and, by inference, the strongest historical genetic drift) were most genetically differentiated from mainland grey foxes, and vice versa, indicating genetic drift drives genome‐wide divergence. Nonetheless, outlier tests identified 3.6–6.6% of loci as high FST outliers, suggesting that despite strong genetic drift, divergent selection contributes to population divergence. Patterns of similarity among populations based on high FST outliers mirrored patterns based on morphology, providing additional evidence that outliers reflect adaptive divergence. Extremely low genetic variation and small Ne in some island fox populations, particularly on San Nicolas Island, suggest that they may be vulnerable to fixation of deleterious alleles, decreased fitness and reduced adaptive potential.

Habitat Use by Coyotes in Southeastern Nebraska

We studied the effect of group size on survival of black-tailed prairie dogs (Cynomys ludovicianus ) relocated to 12 experimental plots in Colorado to determine success of reintroductions. Six groups of 10, 3 groups of 30, and 3 groups of 60 prairie dogs were randomly assigned and released from July to October 1990 in 6 1-, 3 3-, and 3 6-ha plots, respectively, in former prairie dog colonies that were extirpated by sylvatic plague (Yersinia pestis) during fall 1988. We recaptured prairie dogs in plots during September-October 1990, February-March 1991, June 1991, and September-October 1991 to estimate survival. We used capture-recapture models to estimate survival and recapture rates. Daily survival rates between release and first recapture were different for 10- (0.9767, SE = 0.0044), 30- (0.9854, SE = 0.0023), and 60-animal groups (0.9914, SE = 0.0016) (P < 0.001) and were directly related to group size (P < 0.001). The number of progeny captured per animal released was greater in the 60- (? = 0.79, SE = 0.06) than in the 10- (? = 0.28, SE = 0.21) animal plots (P = 0.028), but did not vary between the 60- and 30-animal plots (? = 0.62, SE = 0.09) (P = 0.333) or between the 30- and 10-animal plots (P = 0.156). The 60-animal groups attracted more immigrants than the 10- or 30-animal groups. Ratios of the number of prairie dogs 1 year after release (survivors and progeny) to those released varied (P = 0.018) among the 10- (? = 0.46, SE = 0.21), 30- (? = 0.81, SE = 0.09), and 60- (? = 1.17, SE = 0.08) animal groups and were related linearly (P = 0.006) but not quadratically (P = 0.750) to the number of animals released. One year after release, only the 60-animal groups had more survivors and progeny than the number of prairie dogs released. We recommend releasing a minimum of 60 animals/site in areas with potential immigrants.

Estimating coyote density from mark-resight surveys

by Althoff (1978), Andelt et al. (1979), and Andelt and Gipson (1979). However, these authors did not report on habitat use, and information of this nature from studies conducted elsewhere is limited (Ozoga and Harger 1966; Chesness and Bremicker, unpubl. rep., Coyote Res. Workshop, Denver, Colo., 1974; Hilton 1978; Litvaitis and Shaw 1980). In this paper, we report the results of a study designed to investigate habitat use by coyotes in an extensively farmed region of southeastern Nebraska.

LONG-TERM TRENDS IN MULE DEER PREGNANCY AND FETAL RATES IN COLORADO

Because studies of coyote (Canis latrans) density have lacked standardization and estimates of variance, we conducted a mark-resight study of 17 coyotes on the Rocky Mountain Arsenal (RMA), Colorado, to provide the basis for recommending survey design. Radiolocations of some coyotes on and off the study area verified that geographic closure of the population was violated. Thus, we estimated coyote population size with an estimator that allows for immigration and emigration. Using program NOREMARK (a mark-resight program; Neal et al. 1993), we estimated that a daily population of 50 (95% CI = 34-81, 0.71 /km 2 ) coyotes and a total population of 73 (95% CI = 50-121) coyotes used the study area during December 1990-January 1991. With Monte Carlo simulations in program NOREMARK, we demonstrated that if ≥20% of the population is marked and observed during each survey, it is more cost effective to decrease bias and improve precision by conducting additional surveys rather than capturing and marking more coyotes. We recommend conducting simulations with program NOREMARK to determine the best way to decrease bias and improve precision while minimizing cost of a coyote mark-resight study