Global expansion of human activities is associated with the introduction of novel stimuli, such as anthropogenic noise, artificial lights, and chemical agents. Progress in documenting the ecological effects of sensory pollutants is weakened by sparse knowledge of the mechanisms underlying these effects. This severely limits our capacity to devise mitigation measures. Here, we integrate knowledge of animal sensory ecology, physiology, and life history to articulate three perceptual mechanismsmasking, distracting, and misleadingthat clearly explain how and why anthropogenic sensory pollutants impact organisms. We then link these three mechanisms to ecological consequences, and discuss their implications for conservation. We argue that this framework can reveal the presence of 'sensory danger zones', hotspots of conservation concern where sensory pollutants overlap in space and time with an organism's activity, and foster development of strategic interventions to mitigate the impact of sensory pollutants. Future research that applies this framework will provide critical insight to preserve the natural sensory world.

Bats (Mammalia: Chiroptera) are among the most successful mammals and likely display the widest range of mating systems within the Class. One mating system that is underrepresented in the Chiroptera is lek breeding, which is characterized by aggregations of sexually displaying males that are visited by receptive females who appraise male displays and actively choose mates, yet receive no direct benefits such as assistance in parenting. Leks are thought to form when males can defend neither resources nor females, making it more economical to establish small breeding territories and self‐advertise through sexual displays. Lekking is rare in mammals, and it has been suggested that a lack in the mobility required by females to economically seek out aggregations of sexually displaying males may explain this rarity. Bats, like birds, do not suffer reduced mobility and yet out of over a thousand described species, only one has been confirmed to breed in leks. We examine the rarity of lekking in bats by providing an overview on the current state of knowledge of their mating systems and discuss the ecological and social determinants for the observed trends, contrasted with the prerequisites of lek‐breeding behaviour. We use the breeding behaviour of New Zealand's lesser short‐tailed bat Mystacina tuberculata, which is believed to be a lek breeder, as a case study for the examination of potential lekking behaviour in bats, and highlight the importance of such research for the development of effective conservation strategies.

The lesser short‐tailed bat, Mystacina tuberculata, is the only native mammalian pollinator in New Zealand and the only fully temperate bat pollinator in the world. Although this unique status as a pollinator is well recognized, its reduced abundance and cryptic behaviour means little research has been undertaken to assess the contribution of the lesser short‐tailed bat (hereafter ‘short‐tailed bat’) to pollination in New Zealand. Accordingly, pollination by short‐tailed bats has been assumed to be comparatively inconsequential, and the potential impacts of the bat's widespread extirpation have been overlooked. The recent discovery that the short‐tailed bat is a major pollinator for at least some of the plants it visits emphasizes the importance of exploring this species' role as a pollinator. Here, our aim was to provide an assessment of the competition for short‐tailed bat pollination through study of the temporal variation of flowering. Bats were sampled for pollen, and phenology surveys were conducted simultaneously. We found that the amount and type of pollen carried by the bats varied temporally, with one pollen type dominating samples at any given time. The two plants most consistently observed in the pollen samples flowered sequentially with little temporal overlap, suggesting that their flowering phenology may be adapted to minimize competition for the pollination services of the short‐tailed bat.

Natural sensory environments, despite strong potential for structuring systems, have been neglected in ecological theory. Here, we test the hypothesis that intense natural acoustic environments shape animal distributions and behavior by broadcasting whitewater river noise in montane riparian zones for two summers. Additionally, we use spectrally-altered river noise to explicitly test the effects of masking as a mechanism driving patterns. Using data from abundance and activity surveys across 60 locations, over two full breeding seasons, we find that both birds and bats avoid areas with high sound levels, while birds avoid frequencies that overlap with birdsong, and bats avoid higher frequencies more generally. We place 720 clay caterpillars in willows, and find that intense sound levels decrease foraging behavior in birds. For bats, we deploy foraging tests across 144 nights, consisting of robotic insect-wing mimics, and speakers broadcasting bat prey sounds, and find that bats appear to switch hunting strategies from passive listening to aerial hawking as sound levels increase. Natural acoustic environments are an underappreciated niche axis, a conclusion that serves to escalate the urgency of mitigating human-created noise.

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