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The assumption that activity and foraging are risky for prey underlies many predator–prey theories and has led to the use of predator–prey activity overlap as a proxy of predation risk. However, the simultaneous measures of prey and predator activity along with timing of predation required to test this assumption have not been available. Here, we used accelerometry data on snowshoe hares (Lepus americanus) and Canada lynx (Lynx canadensis) to determine activity patterns of prey and predators and match these to precise timing of predation. Surprisingly we found that lynx kills of hares were as likely to occur during the day when hares were inactive as at night when hares were active. We also found that activity rates of hares were not related to the chance of predation at daily and weekly scales, whereas lynx activity rates positively affected the diel pattern of lynx predation on hares and their weekly kill rates of hares. Our findings suggest that predator–prey diel activity overlap may not always be a good proxy of predation risk, and highlight a need for examining the link between predation and spatio-temporal behaviour of predator and prey to improve our understanding of how predator–prey behavioural interactions drive predation risk. [ABSTRACT FROM AUTHOR]

Climate warming is causing asynchronies between animal phenology and environments. Mismatched traits, such as coat color change mismatched with snow, can decrease survival. However, coat change does not serve a singular adaptive benefit of camouflage, and alternate coat change functions may confer advantages that supersede mismatch costs. We found that mismatch reduced, rather than increased, autumn mortality risk of snowshoe hares in Yukon by 86.5% when mismatch occurred. We suggest that the increased coat insulation and lower metabolic rates of winter‐acclimatized hares confer energetic advantages to white mismatched hares that reduce their mortality risk. We found that white mismatched hares forage 17–77 min less per day than matched brown hares between 0°C and −10°C, thus lowering their predation risk and increasing survival. We found no effect of mismatch on spring mortality risk, during which mismatch occurred at warmer temperatures, suggesting a potential temperature limit at which the costs of conspicuousness outweigh energetic benefits. [ABSTRACT FROM AUTHOR]

Snowshoe hare cycles are one of the most prominent phenomena in ecology. Experimental studies point to predation as the dominant driving factor, but previous experiments combining food supplementation and predator removal produced unexplained multiplicative effects on density. We examined the potential interactive effects of food limitation and predation in causing hare cycles using an individual‐based food‐supplementation experiment over‐winter across three cycle phases that naturally varied in predation risk. Supplementation doubled over‐winter survival with the largest effects occurring in the late increase phase. Although the proximate cause of mortality was predation, supplemented hares significantly decreased foraging time and selected for conifer habitat, potentially reducing their predation risk. Supplemented hares also lost less body mass which resulted in the production of larger leverets. Our results establish a mechanistic link between how foraging time, mass loss and predation risk affect survival and reproduction, potentially driving demographic changes associated with hare cycles. [ABSTRACT FROM AUTHOR]

Interactions between Coyote (Canis latrans) and Golden Eagle (Aquila chrysaetos) are complex and likely not yet fully documented or understood. I observed a Coyote prey on a Black-tailed Prairie Dog (Cynomys ludovicianus) at the edge of a large colony in Grasslands National Park, Saskatchewan. The prairie dogs were vigilant toward three Golden Eagles circling above, and the Coyote apparently used this to its advantage. As such, the eagles appeared to facilitate the ability of the Coyote to rush in virtually undetected and prey on a prairie dog that was distracted by the avian predators. This observation is of scientific interest because it is another example of the varied interactions between Coyotes and Golden Eagles, which is competitive and includes kleptoparasitism. [ABSTRACT FROM AUTHOR]

Canada Lynx (Lynx canadensis) is a specialist predator of Snowshoe Hare (Lepus americanus), which dominates its diet. However, hare populations cycle over 9-11 years, and many lynx disperse or starve during cyclic lows of their prey. Here, I report observations of Canada Lynx scavenging and attempting to prey on Common Raven (Corvus corax). In addition, I provide a brief review of birds as a food item of lynx. These are the first observations of ravens as a food source for lynx and may be a response to lynx being malnourished. The value of these observations is that they highlight the adaptability of some lynx to opportunistically use novel prey species during the decline phase of cyclic Snowshoe Hare. [ABSTRACT FROM AUTHOR]

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Belted Kingfishers (Megaceryle alcyon) are highly piscivorous and rarely take prey other than fish. Here, I report an observation of a male Belted Kingfisher preying on a Western Water Shrew (Sorex navigator) in a small boreal stream in southwestern Yukon. This observation provides farther evidence that Belted Kingfishers will occasionally prey on riparian small mammals when the opportunity arises and points to piscivorous birds as apparently novel predators of shrews. [ABSTRACT FROM AUTHOR]

Osprey (Pandion haliaetus) are piscivores, and observations of them preying on non-fish species are rare. I observed an Osprey preying on a Long-tailed Vole (Microtus longicaudus) that was swimming in the Sikanni Chief River in northeastern British Columbia. This is one of few reports of an Osprey preying on a small mammal, and it provides further evidence that Osprey may prey on such species as the opportunity arises. This observation also points to the apparent vulnerability of small rodents to novel predators while they are swimming. [ABSTRACT FROM AUTHOR]

Most species of bats (Chiroptera) are nocturnal, and diurnal activity is only occasionally reported. I observed a Spotted Bat (Euderma maculatum) flying along a lakeshore in the Okanagan Valley of southcentral British Columbia, Canada, in mid-afternoon. The Spotted Bat flew along the shoreline and drank from the lake. During the course of its flight, the Spotted Bat was attacked by a Belted Kingfisher (Megaceryle alcyon), but it escaped. This is the first reported observation of a Spotted Bat active during the daytime. It is also the first reported observation of attempted prédation of a bat by a Belted Kingfisher. It is not known how prevalent daytime activity is in Spotted Bats, but this observation supports the hypothesis that prédation risk may be high for bats that are active during the day. [ABSTRACT FROM AUTHOR]

The article provides information on a report on the observation of Sorex palustris, commonly known as American Water Shrew, relative to its predation by an Martes americana or American Marten. It states that the incidence of the predation of American Water Shrew are rare, despite of its large skull which can be easily identified in the stomachs of the predator. It offers a brief information on the live-trapping study of American Marten near Watson Lake, Yukon in relation to shrew predation.