Direct Observations of Owls and Heteromyid Rodents: Can Predation Risk Explain Microhabitat Use?

Abstract

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Chronobiology by moonlight

“…The effect of moonlight as an indirect cue for predation risk for rodents received considerable attention during the last decades [4,[58][59][60]. Rodents are preyed upon by owls and mammalian predators, whose predation efficiency increases during full Moon nights [4,59,61 -64]; consequently, many rodent species reduce activity or shift it to more sheltered habitats [58,65 -70].…”

Ecology and natural history of Akodon lindberghi (Rodentia, Sigmodontinae) in southeastern Brazil

“…The habitat modification would be causing a decline in the density of vegetation cover, with a reduction in refuges and a rise in vulnerability. The presence of human activity, such as livestock, would be contributing strongly to this decrease, favouring those individuals of smaller body mass by increasing their probability of taking refuge (SIMONETTI, 1989;LONGLAND & PRICE, 1991;MESERVE et al, 1993).…”

Moonlight avoidance in gerbils reveals a sophisticated interplay among time allocation, vigilance and state-dependent foraging

“…Increased illumination appears to aid predators such as owls and foxes more than it aids their rodent prey (Kotler et al 1988(Kotler et al , 1991Longland & Price 1991). From the rodent's point of view, it is better that the predator does not encounter the prey, but this is more difficult on bright nights.…”