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.

Evidence suggests that predation on domestic sheep hy coyotes (Cnnis latrans) is caused printarily by breeding pairs with territories overlapping sheep. Accordingly, we investigated t~llnerahility of coyotes to removal methods relative to factors associated with reproduction and territoriality LVe collected live and lethal coyote capture data during April 1993-Febn~ar?, 1998 on a north-coastal California sheep ranch. Routine coyote removal was conducted in response to sheep depredation before and during (part of! the stucly. Younger (nonbreed~ig) coyotes generally were more c~ilnerable to captnre than older (potentially breeding) individnals. although age bias varied among removal methods. Recaptures of radiocollared coyotes in foothold traps and snares indicated a bias toward progressively younger indi\iduals (juv > yearling > ad; P = 0.002). Proportionally more jnvenile and yearling coyotes were remotred by M-44s (sotliunr cyanide ejectors) than by traps and snares (P = 0.016). \lie found no difference between traps and snares in the ages of coyotes taken (P = 0.50). \'~ilnerability of yorlnger coyotes was likely elevated by lack of experience arrd rtlore tinie spent in nnfarrriliar areas where they were least able to avoid capture devices. Coyotes were caught more often than expected oritside of core areas of their territories with both traps (P =: 0.001) and snares (P= 0.02). Older coyotes were most vulnerable in spring and summer when rearing pups, after most depredation occurred. Kadiocollared breeders (P = 0.012) and uncollared coyotes of breeding age (P = 0.052) werr captured less often during the non-pup-rearing periocl tlran the pup-rearing period. These results suggest conventior~al control in ~~o r t h e r n California is poorly suited to the segment of the coyote poptilation killing the most sheep. particnlarly dnring the time of year when most sheep depredation occurs. Efficacy of control methocis might be improved by consen~ative use of conventional devices to minimize learned avoid;ince by coyotes, and bv grrater reliance on methods such as livestock protection collars that are specific to depredating ir~di\id~~als throughout the year,

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Recent studies have revealed that western populations of little brown bats (Myotis lucifugus) in North America exhibit different hibernation behavior than their eastern counterparts. Understanding these differences is essential for assessing the risk white-nose syndrome (WNS) poses to western bat populations. We used acoustic monitoring and radiotelemetry to study the overwintering behavior of little brown bats near Juneau, Alaska during 2011–2014. Our objectives were to identify the structures they use for hibernation, measure the microclimates within those structures, and determine the timing of immergence and emergence and the length of the hibernation season. We radiotracked 10 little brown bats to underground hibernacula dispersed along two ridge systems. All hibernacula were ≤ 24.2 km from where the bats were captured. Eight bats hibernated in the “Milieu Souterrain Superficiel” (MSS), a network of air-filled underground voids between the rock fragments found in scree (talus) deposits. Two bats hibernated in holes in the soil beneath the root system of a tree or stump (rootball). At least two hibernacula in the MSS were reused in subsequent years. Average MSS and rootball temperatures were warmer and more stable than ambient temperature and were well below the optimal growth range of the fungus that causes WNS. Temperatures in the MSS dropped below freezing, but MSS temperatures increased with depth, indicating bats could avoid subfreezing temperatures by moving deeper into the MSS. Relative humidity (RH) approached 100% in the MSS and under rootballs and was more stable than ambient RH, which also was high, but dropped substantially during periods of extreme cold. Acoustic monitoring revealed that bats hibernated by late October and began emerging by the second week of April; estimates of minimum length of the hibernation season ranged from 156 to 190 days. The cold temperatures, dispersed nature of the hibernacula, and close proximity of hibernacula to summering areas may slow the spread and reduce the impacts of WNS on local populations of little brown bats.

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