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During periods of predation risk, prey adopt antipredator behaviours to maximise chances of survival, such as increased vigilance, reduced foraging time, shifting to safe habitat, and group formation. To effectively balance resource acquisition and antipredator behavior, prey animals make use of cues within their environment that provide them accurate information about the realistic threat of predation. Using camera traps, we tested vigilance and feeding behavioural responses of two naturally occurring ungulate species roe deer and moose to cues from naturally occurring brown bear and novel Amur tiger predators. We found that roe deer and moose vigilance and feeding behaviours were not affected by either visual or olfactory cues from predators, suggesting that ungulates in this system do not respond differently to novel predator cues. There are a number of potential explanations for this surprising lack of response to any predator cues: a) habituation to uninformative cues is important; b) ungulates might have relied more heavily on other cue types, such as auditory cues, or cues in combination; and, c) constraints on dispersal and/or resources may result in prey being forced to remain in high risk food patches, and continued prioritization of feeding over vigilance. We therefore, recommend that in the future studies regarding cues should involve a combination of cues at a similar location to increase predation risk to the animals to maximise prey response. To our knowledge, this is the first study to lay out the foundation of the ecological influences of captive Amur tiger on prey behaviors in the wild environment. [ABSTRACT FROM AUTHOR]

El Niño Southern Oscillation (ENSO) linked climate has been known to be associated with several rodent species, but its effects on rodent community at both spatial and temporal scales are not well studied. In this study, we investigated the possible causal chain relating ENSO, precipitation, temperature, and vegetation index (normalized difference vegetation index, NDVI) to rodent abundance for 14 sympatric rodent species in 21 counties of semiarid grasslands in Inner Mongolia, China, from 1982 to 2006. We found that both precipitation and temperature showed a generally direct positive effect on rodent abundance in many species in the current year, but indirect effects that operate through NDVI in the current or following year could have a reverse effect on abundance. We described one ENSO-linked precipitation bottom-up chain and three ENSO-linked temperature bottom-up chains. These observed bottom-up links reveal that in El Niño years, or 1 year after La Niña years, or 2 years after El Niño years, ENSO-driven climate or vegetation factors tend to increase population abundances of many sympatric rodent species in this region. We also found time-lag effects and the life-history strategy (i.e., functional groups of hibernating behavior, activity rhythm, or food habits) also contribute to the observed complicated effects of SOI on precipitation, temperature, NDVI, and ultimately rodent abundance. [ABSTRACT FROM AUTHOR]