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Abstract

A long standing interest in ecology has been to understand the effects of abiotic factors on organisms and their interactions within ecological communities. This understanding has become increasingly important in light of rapid anthropogenic climate change. One of the most under-studied aspect of climate change is changing wind speed, which are generally decreasing in terrestrial environments globally. While wind is a nearly ubiquitous part of the environment, little effort has been put into synthesizing our understanding of how wind influences interspecific interactions. We reviewed the literature to synthesize our current understanding of the effects of wind with a specific focus on predators-prey interactions. We identified three primary mechanisms by which wind influences predator-prey interactions: detection of the other species, locomotion, and physical disturbance. We found that wind can have diverse effects that can both strengthen or dampen the effects of predators on their prey. However, these effects are context dependent and forecasting the effects of slowing wind speed on species interactions will depend on specific traits of the predator, prey, and environment in which they interact.

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... Phenological shiŌs, e.g., migraƟon or Ɵming of alternate resources alter temporal overlap (+/-) [14] Increased demands for feeding reduce vigilance (+) [33] Change in habitat substrate (e.g., snow density) facilitates predator or prey speed (+/-) [64] PolluƟon avoidance (e.g., light polluƟon) restricts movement of predator (-) or prey (+) [47] PolluƟon degrades indirect/direct cues of predaƟon risk (+) [18] ArƟficial lights or noises can disorient predators (-) or prey (+) [63] Change in matrix permeability restricts movement of predators (-) or prey (+) [10] Increased wind speed along forest edges obscures cues of predators (+) [53] Decreased availability or accessibility of refuge (+) [19] Loss of apex predator increases mesopredator pressure (+) [20] SituaƟons are safe, but are perceived as dangerous (+) [58] Defenses against exƟnct predators constrain prey responses to extant predators (+) [58] Introduced predator habitat domain complements domain of naƟve predator (+) [48] Prey are naive to cues of introduced predators (+) [21] Non-naƟve plant provides a new, effecƟve refuge (-) [27] Change in predator funcƟonal traits alters aƩack rates on prey (+/-) [66] Change in predator diet changes cues (e.g., urine chemistry) (+) [57] Change in predator social behavior alters pack size (+/-) [ behavioral defenses (e.g., group defense) that represent adaptations to traits of historical predators (e.g., predator attack mode) [41]. Prey can also flee to a refuge when attacked. ...
... At finer scales, prey may fail to avoid predators for two general reasons (Figure 1): prey cannot detect predators, or the costs of avoiding predators outweigh the benefits. Important cues of predators might degrade or attenuate quickly in novel stages (e.g., decreased wind speed [53] or light pollution [54]), decreasing the likelihood that prey detect predators. Differences in sensory acuity among species [55] may therefore partly explain differences in ability of species to detect predators in novel habitats. ...
... Text boxes within a column describe changes in the corresponding step of the predation sequence (overlap, avoid, escape), while text boxes within a row describe consequences of the corresponding form of novelty (climate change, pollution, etc.). SeeFigure 2for additional information and examples regarding the steps of the predation sequence[10,14,[18][19][20][21][22]27,33,47,48,53,57,58,63,64,66]. ...
Article
Ecological novelty, when conditions deviate from a historical baseline, is increasingly common as humans modify habitats and communities across the globe. Our ability to anticipate how novelty changes predator–prey interactions will likely hinge upon the explicit evaluation of multiple forms of novelty, rather than a focus on single forms of novelty (e.g., invasive predators or climate change). We provide a framework to assess how multiple forms of novelty can act, alone or in concert, on components shared by all predator–prey interactions (the predation sequence). Considering how novelty acts throughout the predation sequence could improve our understanding of predator–prey interactions in an increasingly novel world, identify important knowledge gaps, and guide conservation decisions in the Anthropocene.
... Many factors contribute to global wind declines, including disproportional warming at the poles that decreases thermal gradients and human land use patterns that decrease unobstructed wind (e.g., afforestation and urbanisation) (McVicar et al. 2012). Current research suggests wind can be a key factor for many organisms in relation to locomotion, communication, and foraging (Cherry and Barton 2017). This work supports the need for an even broader understanding of how species generally respond to the direct and indirect effects of wind. ...
... Previous research on the effects of wind includes investigations of predators (Cherry and Barton 2017) and plants (Gardiner et al. 2016). Predators have been shown to be indirectly impacted by changes in wind patterns due to pheromone signalling and the physical ability to hunt (observe prey, fly to catch prey) (Cherry and Barton 2017). ...
... Previous research on the effects of wind includes investigations of predators (Cherry and Barton 2017) and plants (Gardiner et al. 2016). Predators have been shown to be indirectly impacted by changes in wind patterns due to pheromone signalling and the physical ability to hunt (observe prey, fly to catch prey) (Cherry and Barton 2017). In direct response to increasing wind exposure, herbaceous plants develop thicker cell walls, allocate more resources to roots, and produce chemicals that increase lignification (de Langre 2008). ...
Article
Global change research has shown how altering factors like temperature and precipitation can impact insect ecology. However, despite global changes in wind patterns, the effects of altering wind have been relatively unexplored, and even less is understood about indirect effects on insects. To better understand indirect effects of wind on pea aphids ( Acyrthosiphon pisum (Harris); Hemiptera: Aphididae), we performed two experiments using different techniques for simulating mechanical stimulation effects from wind. First, we used either a brush or leaf to simulate plant-to-plant contact caused by wind. Then we tested the indirect effects of wind by distinguishing between wind and wind plus plant contact produced by adjacent plants. In the first experiment, aphid fecundity was reduced on plants with the leaf-to-plant treatment compared to the control. In the second experiment, wind treatments reduced pea aphid fecundity, but wind did not interact with plant density. Our results further the idea that altering wind patterns can influence plant–insect interactions. We also show that more research is necessary to disentangle how and why wind indirectly influences herbivores. Future research should focus on how pea aphid responses to wind change due to the methodology of wind exposure and interactions with additional biotic and abiotic factors.
... Many other environmental gradients affect various sensory modalities at levels that are not necessarily stressful physically (Weissburg et al., 2014), but we lack investigations that explore the effect of sensory stress on TMIEs. Some environmental features, such as fluid flow, can both physically constrain animal locomotion and diminish sensory perception (Cherry & Barton, 2017;Weissburg et al., 2003), which further complicates the relationship of predator controls across environmental gradients. ...
... Sparrowhawk attack success on the shorebird redshanks decreases with wind speed due to reduced flight control in high wind conditions and an increased ability of redshanks to evade hawk attacks (Quinn & Cresswell, 2004). Thus, shorebird consumption of invertebrate prey may increase under these conditions in which their ability to evade hawk attacks and forage are not compromised (Cherry & Barton, 2017). In physically harsh contexts, sensory stress no longer regulates predator controls but how physical stress simultaneously affects predator and prey performance (i.e., consumer/prey stress models; Menge & Olson, 1990) will determine basal resource abundance. ...
... Odor-mediated predator-prey interactions across a diverse array of taxa are prevalent in both aquatic and terrestrial systems that contain environmental features that impose substantial sensory stress at levels that are not physically limiting (Dicke & Grostal, 2001;Ferrari et al., 2010;Kats & Dill, 1998;Parsons et al., 2018). Like in aquatic environments, wind can physically constrain animal locomotion and alter odor plume structure to reduce chemosensory perception (Cherry & Barton, 2017;Wilson et al., 2015). Other sensory modalities used by prey to detect predators are also impaired in environments that are not physically harmful, such as visual detection in turbid waters (Chivers et al., 2013) and mechanosensory abilities in moderate turbulence (Buskey et al., 2012). ...
Article
Full-text available
Predators affect community structure by influencing prey density and traits, but the importance of these effects often is difficult to predict. We measured the strength of blue crab predator effects on mud crab prey consumption of juvenile oysters across a flow gradient that inflicts both physical and sensory stress to determine how the relative importance of top predator density‐mediated indirect effects (DMIEs) and trait‐mediated indirect effects (TMIEs) change within systems. Overall, TMIEs dominated in relatively benign flow conditions where blue crab predator cues increased oyster survivorship by reducing mud crab–oyster consumption. Blue crab DMIEs became more important in high sensory stress conditions, which impaired mud crab perception of blue crab chemical cues. At high physical stress, the environment benefitted oyster survival by physically constraining mud crabs. Thus, factors that structure communities may be predicted based on an understanding of how physical and sensory performances change across environmental stress gradients.
... In addition, it took the birds twice as long to successfully capture caterpillars on wind-exposed plants than on non-exposed controls. Great tits are visual foragers (Houston, Krebs, & Erichsen, 1980) and although we observed the birds visiting both wind-exposed and still plants during foraging, they probably have difficulty establishing a firm search image for their prey on wind-exposed plants that are in motion (Cherry & Barton, 2017). In this study we investigated the effect of wind in a choice situation which may not realistically reflect wind conditions experienced in the field. ...
... The results from chapter 2 and chapter 3 emphasize the importance of wind and rainfall in studies of plant-herbivore and predator-prey interactions. Changes in these patterns may have the potential to disrupt species interactions and ecosystem function (Barton & Ives, 2014;Cherry & Barton, 2017;Wade, Karley, Johnson, & Hartley, 2017). ...
Thesis
Plants play a central role in mediating species interactions within and between trophic levels. Plants quality and quantity can affect the behavior and development of insect herbivores. Furthermore, these effects may cascade up to higher trophic levels, such as parasitoids and hyperparasitoids, through bottom-up processes. However, in nature, these biotic interactions are inevitably influenced by their complex abiotic environment. Understanding abiotic-biotic interactions is becoming increasingly important in a rapidly changing world. The aim of my thesis was to explore how these climate-related factors impact interactions involving plants, insect herbivores, predators, parasitoids and hyperparasitoids. I first investigated effects of simulated wind and rain on the performance of insect herbivores feeding on their host plants. Secondly, I examined the impact of simulated heatwaves on interactions between parasitoids and hyperparasitoids. In a greenhouse experiment (chapter 2), I studied direct and plant-mediated effects of simulated wind on the performance of two insect herbivores, Plutella xylostella and Pieris brassicae, feeding on black mustard plants, Brassica nigra. Plants were exposed to four different wind treatments that allowed me to separate direct and indirect effects of wind exposure on herbivores. Morphological and chemical traits of plants and developmental parameters of insect herbivores were measured. The results showed that adults of P. brassicae grew larger under conditions of direct wind-exposure, but adults of P. xylostella did not. Development time of both herbivores was longer. I further conducted a choice experiment to study effects of wind exposure on the preference of an avian predator (Parus major) for caterpillars of P. brassicae in an observation room. I found that caterpillars on plants without wind exposure had a higher predation risk than caterpillars on plants with wind exposure. I conclude that P. brassicae can perceive lower predation risk under windy condition, and extends its developmental program by prolonging its larval development to achieve a lager adult body size. Using the same model plant and insect species, I tested the effects of simulated heavy rain on the performance of the two herbivores on plants (chapter 3). Rainfall regimes were set either as a single long or as three short rain showers per day. I found that rain exposure extended the development time of both herbivores and had a strong negative effect on the survival of P. xylostella, but not on that of P. brassicae. Effects of rain exposure on adult body mass depended on species and rainfall frequency. Overall, plant-mediated effects of rain exposure on the herbivores were generally small. The results suggest that changes in the duration and frequency of rainfall may alter the population dynamics of insects and insect community structure. In a lab experiment (chapter 4), I examined the effects of different temperature regimes on reproduction and functional responses of two hyperparasitoid species, Gelis agilis and Acrolyta nens. Host cocoons of two different ages were exposed to three different temperature regimes that represent cool, normal and warm conditions in the Netherlands. I found that temperature had stronger negative effects on the reproduction of G. agilis (a less fecund species) than on A. nens (a more fecund species). Host cocoons of C. glomerata developed faster under warmer conditions. Therefore, I conclude that exposure to simulated heatwaves may change community structure at higher trophic levels. Using the same temperature regimes, I further tested the effects of simulated heatwaves on intrinsic competition between two hyperparasitoids, Lysibia nana and A. nens (chapter 5). I showed that L. nana benefited in competition under warmer conditions. Higher temperature enhanced the competitive advantage of the superior competitor. The results indicate that heatwaves associated with global warming may have the potential to reduce species coexistence in the fourth trophic level. In conclusion, abiotic factors (wind, rainfall, temperature) had important impacts on the plant-herbivore and parasitoid-hyperparasitoid multitrophic interactions that I tested in this thesis. Wind and rainfall exposure clearly affected the performance of insect herbivores. An extended developmental program was observed in P. brassicae as a result of a reduction in predation risk under windy condition. Overall, plant-mediated effects of wind and rainfall exposure were generally small. Exposure to simulated heatwaves differentially influenced reproduction and functional responses of two hyperparasitoid species. Moreover, simulated heatwaves negatively affected fitness of species and species coexistence at the terminal end of food chain. Future studies integrating various climate-related abiotic factors into multitrophic interactions at global scale are urgently needed to mitigate the ecological effects of climate change.
... Despite this, physical characteristics that impact foraging behavior and success are usually excluded. Examples include the effects of habitat structure in creating refuges for prey Beets 1993, Hixon andCarr 1997) and the role of wind or water flow on the agility of predators or prey (Bejarano et al. 2017, Cherry andBarton 2017). Although some trophic cascades have been conclusively identified in relatively homogenous systems (Polis et al. 2000), the consideration of physical processes in more complex ecosystems is crucial given that they may mediate the structure of food webs, and could, if excluded, confound the interpretation of interspecies interactions. ...
... Food-web theory is increasingly embracing the contribution of physical processes and habitat in the mediation of trophic interactions (Rogers et al. 2014, Cherry and Barton 2017, Robson et al. 2017, Silliman and He 2018. In structurally complex environments such as coral reefs, it is clear that bottom-up processes play an important role in structuring guilds and influencing their interactions. ...
Article
Global overfishing of higher‐level predators has caused cascading effects to lower trophic levels in many marine ecosystems. On coral reefs, which support highly diverse food‐webs, the degree to which top‐down trophic cascades can occur remains equivocal. Using extensive survey data from coral reefs across the relatively unfished northern Great Barrier Reef (nGBR), we quantified the role of reef sharks in structuring coral reef fish assemblages. Using a structural equation modelling (SEM) approach, we explored the interactions between the shark abundance and teleost mesopredator and prey functional group density and biomass, whilst explicitly accounting for the potentially confounding influence of environmental variation across sites. While a fourfold difference in reef shark density was observed across our survey sites, this had no impact on either the density or biomass of teleost mesopredators or prey, providing evidence for a lack of trophic cascading across nGBR systems. Instead, many functional groups, including sharks, responded positively to environmental drivers. We found reef sharks to be positively associated with habitat complexity. In turn, physical processes such as wave exposure and current velocity were both correlated well with multiple functional groups, reflecting how changes to energetic conditions and food availability, or modification of habitat affect fish distribution. The diversity of species within coral reef food webs and their associations with bottom‐up drivers likely buffers against trophic cascading across GBR functional guilds when reef shark assemblages are depleted, as has been demonstrated in other complex ecosystems.
... Our aim in using these qualitative assessments was to understand whether wolves chose ambush locations based on olfactory concealment. While our approach does not capture all of the nuances of wind turbulence and direction during hunting attempts, it allowed us to assess how prevailing wind direction influences ambush behavior at a finer scale than any previous study we are aware of (Conover 2007;Cherry and Barton 2017). ...
... To prevent detection, wolves predominantly chose ambush locations that had olfactory concealment (89-94% of attempts) where beavers likely could not detect them. Although this was expected, empirically demonstrating how wind direction influences the ambush behavior of carnivores has been difficult, at best, with most studies only able to correlate habitat selection or hunting success with wind speed or direction (Stander and Albon 1993;Conover 2007;Cherry and Barton 2017). To our knowledge, this is the only study that demonstrates that carnivores can choose ambush locations with olfactory concealment from their prey (see Conover 2007 and Cherry and Barton 2017 for a review of olfaction in predator-prey interactions). ...
Article
Full-text available
Comprehensive knowledge of ambush behavior requires an understanding of where a predator expects prey to be, which is generally un-knowable because ambush predators often hunt mobile prey that exhibit complex, irregular, or inconspicuous movements. Wolves (Canis lupus) are primarily cursorial predators, but they use ambush strategies to hunt beavers (Castor canadensis). Terrestrial beaver activity is predictable because beavers use well-defined, conspicuous habitat features repeatedly. Thus, studying where wolves wait-in-ambush for beavers provides a unique opportunity to understand how predators choose ambush locations in relation to prey activity. We searched 11 817 clusters of GPS locations from wolves in the Greater Voyageurs Ecosystem, International Falls, MN, and documented 748 ambushing sites and 214 instances where wolves killed beavers. Wolves chose ambush locations: 1) with olfactory concealment to avoid detection from the highly developed olfactory senses of beavers and 2) close (generally <5 m) to beaver habitat features to take advantage of beavers' inability to visually detect motionless predators. Our work describes in detail the ambush strategies wolves use to hunt beavers and continues to overturn the traditional notion that wolves rely solely on cursorial hunting strategies. We also demonstrate that ambush predators can anticipate the movements and behavior of their prey due to a fundamental understanding of their prey's sensory abilities. Wolves, therefore, and likely ambush predators in general, appear capable of simultaneously accounting for abiotic and biotic factors when choosing ambush locations, ultimately allowing them to counter and capitalize on the sensory abilities of their prey.
... turbulence) pose biomechanical challenges [9][10][11][12][13] that push manoeuvrability limits in flying insects [14] and can impose energetic costs on flight [15]. The mechanical and physiological challenges posed by wind may have important effects on insects' interactions with plants, including herbivory [16,17], and pollinator visitation and landing [18]. Wind also indirectly impacts flying insects by inducing plant movements [19], which can impose additional manoeuvrability challenges [14] In addition to biophysical challenges, wind disperses chemical cues and signals critical for interactions between insects (e.g. ...
Preprint
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Wind is a critical factor in the ecology of pollinating insects such as bees. However, the role of wind in determining patterns of bee abundance and floral visitation rates across space and time is not well understood. Orchid bees are an important and diverse group of neotropical pollinators that harvest pollen, nectar and resin from plants. In addition, male orchid bees collect volatile scents that they store in special chambers in their hind legs, and for which the wind-based dispersal of odors may play a particularly crucial role. Here we take advantage of this specialized scent foraging behavior to study the effects of wind on orchid bee visitation at scent sources in a fragmented tropical forest ecosystem. We find that temporal changes in wind speed and turbulence are correlated with visitation to scent stations within sites, while local landscape structure is a strong determinant of spatial variation in visitation across nearby sites. These results suggest that the increased dispersal of attractive scents provided by wind and turbulence outweighs any biomechanical or energetic costs that might deter bees from foraging in these conditions. Overall, our results highlight the significance of wind in the ecology of these important pollinators in neotropical forests.
... For instance, reduced precipitation affects the interactions, composition and structure of insect populations and communities on plants ( Barton & Ives 2014b;Zhu et al. 2014), a rise in CO 2 concentration affects the performance and development of caterpillars and earthworms (Hobbs 2000), and an increase in UV radiation increases the mortality and morbidity of several amphibian species (Cockell & Blaustein 2001). Among this group of overlooked abiotic factors, wind is the least studied despite being relevant to species and communities (Barton 2014(Barton , 2017Cherry & Barton 2017). Considering that wind speed has decreased worldwide up to 15% in the last 30 years and that this trend is expected to continue in the 21st century (Vautard et al. 2010), wind-effect studies are necessary to fully understand the effects of climate change on the abundance and distribution of animals. ...
... We assume that vigilance increases with the increase of abundances of conspecifics and/or relatives, therefore, foraging activities are expected to be positively correlated with the density of the foraging group that benefits from this vigilance mainly to detect and avoid both terrestrial and aerial predators, or other disturbance sources. On the other hand, we hypothesize that dense foraging groups are expected to generate intra-and inter-specific competitions, which will increase courtship and antagonistic behaviors (Caraco 1979;Henriksen et al. 2015;Cherry and Barton 2017). In addition to the density-dependence of bird activities, whether conditions may shape patterns of these activities (Bezzalla et al. 2019b). ...
Article
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Background: The Shelduck (Tadorna tadorna) is a characteristic waterbird species of inland wetlands in northeastern Algeria. Its wintering behavior in relation to changes of local abundances and foraging group density is poorly known. Objectives: This study aims at monitoring patterns of diurnal activities and the variation of behavioral time-budgets in relation to numbers of wintering Shelducks. It investigates temporal variations of diurnal activities across multiple-time scales and considers their interrelationships. Methods: Assessments of local population abundance were weekly surveyed during two wintering seasons (2010–2012), whereas diurnal activities (feeding, sleeping, swimming, preening, loafing, flying, courtship, and antagonism) were studied three times a month during seven hours (08:00–16:00) using the Scan method. Time budget variations of each behavioral activity were tested using nested ANOVAs following multiple time scales. Generalized linear mixed-effects models (GLMM) tested whether variations in diurnal activities were density-dependent. Results: During the wintering season, Shelduck’s numbers followed a bell-shaped trend, which indicated that the species was typically a wintering migrant in Sabkha Djendli. The first individuals arrived onsite in October-November then numbers reached a peak in January (up to 2400 individuals in 2012) with steady density during December–February, afterward individuals left the site progressively until late April when the site is deserted. During both wintering seasons, diurnal activities was dominated by feeding (60%) followed by sleeping (12%) then swimming and preening with 9% and 8%, respectively. The rest of the activities (loafing, flying, courtship and antagonistic behaviors) had low proportions of time budget. ANOVAs showed that activity time budgets varied significantly following multiple time scales (year, season, month, day, semi-hour). Time budgets of diurnal activities during each wintering season were significantly interrelated. Correlations patterns between the two seasons were similar. GLMMs revealed that the variations of diurnal activities were not density-dependent, except for preening and swimming. Conclusion: During the wintering season, habitats of Sabkha Djendli are important for waterbirds; including the Shelduck that used the lake mainly for food-foraging and resting. The 2400 individuals censused in mid-winter are important locally and at the North African scale. This stresses the need to strengthen the protection status of this wetland and mitigate degradation sources that threaten wintering waterfowl.
... Not all behavioural changes that occur before a storm are necessarily anticipatory of the storm threat itself. Cherry and Barton (2017) review how wind movement of vegetation can make some prey more vigilant for terrestrial predators, while the difficulty of flying in strong winds reduces predation risk from aerial predators. ...
Article
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Behavioural traits are thought to be important determinants of the resilience of animal species to a rapidly changing global climate. Although increasing temperature has taken centre stage in the debate over climate change, animals will have to survive more than just extreme heat to persist in the Anthropocene. The aim of this review is to stimulate interest in the opportunities for integrative and applied behavioural study of how animals can survive life-threatening weather events, in order to help achieve the societal goal of maintaining viable wildlife populations under future climate scenarios. First, using the thermoregulatory behaviour of a hypothetical ground squirrel species as an example, we explore how different scenarios of behavioural flexibility, plasticity, adaptation, exaptation and management action can lead to population persistence or extinction. Next, we propose that considering weather events such as heatwaves, storms and floods, wildfire and drought as selective pressures worthy of investigation provides a new research framework for climate-related conservation behaviour. In our review we provide examples of the responses of animals to different types of weather extremes and describe behavioural adaptations to environments with extreme climates. We give methodological recommendations to jump start climate change research by behaviourists. Finally, we conclude with suggestions for using citizen science and a public video repository to foster evidence-based decision making for managing habitats and prioritizing species conservation efforts in light of the threats to biodiversity posed by climate change.
... Rats are particularly sensitive to 2,4,5-trimethylthiazoline, a component of red fox anal gland secretions (Laska et al., 2005) and mice, rats, and stoats, for example, have been shown to avoid carnivore and apex predator odors (Ferrero et al., 2011;Garvey et al., 2016). Indeed, higher wind speeds have been found to impede predator detection by mule deer (Bowyer et al., 2001) and other mammal species (Cherry and Barton, 2017). The sensory impact of air movement can be further compounded by spillover to the other senses: wind creates acoustic and visual noise, which may reduce detection of stimuli by other senses, further impeding predator detection (Hayes and Huntly, 2005;Carr and Lima, 2010;Francis et al., 2012). ...
Article
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Aeroscapes—dynamic patterns of air speed and direction—form a critical component of landscape ecology by shaping numerous animal behaviors, including movement, foraging, and social and/or reproductive interactions. Aeroecology is particularly critical for sensory ecology: air is the medium through which many sensory signals and cues propagate, inherently linking sensory perception to variables such as air speed and turbulence. Yet, aeroscapes are seldom explicitly considered in studies of sensory ecology and evolution. A key first step towards this goal is to describe the aeroscapes of habitats. Here, we quantify the variation in air movement in two successional stages (early and late) of a tropical dry forest in Costa Rica. We recorded air speeds every 10 seconds at five different heights simultaneously. Average air speeds and turbulence increased with height above the ground, generally peaked midday, and were higher overall at the early successional forest site. These patterns of lower air speed and turbulence at ground level and overnight have important implications for olfactory foraging niches, as chemotaxis is most reliable when air movement is low and steady. We discuss our results in the context of possible selective pressures and observed variation in the foraging ecology, behaviors, and associated morphologies of resident vertebrates, with a focus on mammals. However, these data also have relevance to researchers studying socioecology, invertebrate biology, plant evolution, community ecology and more. Further investigation into how animals use different forest types, canopy heights and partition activities across different times of day will further inform our understanding of how landscape and sensory ecology are interrelated. Finally, we emphasize the timeliness of monitoring aeroecology as global wind patterns shift with climate change and human disturbance alters forest structure, which may have important downstream consequences for biological conservation.
... This may be particularly true in our study as most deer that embarked upon excursions moved to pine forests and hardwood swamps, areas associated with Florida panthers [84,85]. However, it is possible that predation risk decreased temporarily owing to storm conditions [86], or the risk imposed by the storm simply outweighed the risk of predation. ...
Article
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Extreme climatic events (ECEs) are increasing in frequency and intensity and this necessitates understanding their influence on organisms. Animal behaviour may mitigate the effects of ECEs, but field studies are rare because ECEs are infrequent and unpredictable. Hurricane Irma made landfall in southwestern Florida where we were monitoring white-tailed deer (Odocoileus virginianus seminolus) with GPS collars. We report on an opportunistic case study of behavioural responses exhibited by a large mammal during an ECE, mitigation strategies for reducing the severity of the ECE effects, and the demographic effect of the ECE based on known-fate of individual animals. Deer altered resource selection by selecting higher elevation pine and hardwood forests and avoiding marshes. Most deer left their home ranges during Hurricane Irma, and the probability of leaving was inversely related to home range area. Movement rates increased the day of the storm, and no mortality was attributed to Hurricane Irma. We suggest deer mobility and refuge habitat allowed deer to behaviourally mitigate the negative effects of the storm, and ultimately, aid in survival. Our work contributes to the small but growing body of literature linking behavioural responses exhibited during ECEs to survival, which cumulatively will provide insight for predictions of a species resilience to ECEs and improve our understanding of how behavioural traits offset the negative impacts of global climate change.
... While this warming method would require no external heat source, it would still require electricity to power the wind machine. Additionally, using this method would alter local wind patterns, which have been shown to affect some ecosystem processes such as predator-prey interactions [40][41][42]. Wind machines also produce noises [38], which could impair organisms that rely on auditory cues [43] and have cascading indirect effects within communities [44]. Due to their large size, wind machines could be difficult to replicate or lead to pseudoreplication (multiple plots under the same wind machine). ...
Article
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While average global temperatures are increasing, a disproportionate amount of warming can be attributed to increasing nighttime temperatures rather than increasing daytime temperatures. Theory predicts that the timing of warming can generate different effects on organisms and their interactions within ecosystems. This occurs because an organism’s response to warming depends on the current temperature. For example, warming when temperatures are low may have positive effects on an organism, while warming when temperatures are already high may have negative effects on an organism. Most field experiments that examine the ecological effects of climate warming employ warming methodologies that disproportionately elevate daytime warming treatments. The bias towards daytime warming treatments may arise because daytime temperatures can be manipulated with relatively simple and inexpensive technology that capitalizes on solar energy, such as open-top chambers that create a “greenhouse effect” or shade structures that reduce temperatures. However, these popular methods are ineffective when solar radiation is absent, and thus do not create warming treatments that accurately mimic the temporal patterns of climate warming. To encourage the investigation of nighttime warming’s effect on ecosystems, we discuss why daytime and nighttime warming may have different effects on organisms, then present a review of methods that can be employed to elevate nighttime temperature in terrestrial field experiments. For each method, we offer a brief explanation, an evaluation of its pros and cons, and citations for further reference, as well as empirical data when possible. While some are impractical, we attempt to provide a comprehensive list of potential nighttime warming methods in hopes of stimulating ideas and discussions.
... The way wind shapes prey detection ability and thermoregulation in cats also requires investigation. Habitat selection according to wind in a predation-prey context is seldom documented [48]. Underlying factors related to habitat openness include olfactory [49] or visual [50] cues, or more complex patterns [51]. ...
Article
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Background Our picture of behavioral management of risk by prey remains fragmentary. This partly stems from a lack of studies jointly analyzing different behavioral responses developed by prey, such as habitat use and fine-scale behavior, although they are expected to complement each other. We took advantage of a simple system on the Kerguelen archipelago, made of a prey species, European rabbit Oryctolagus cuniculus, a predator, feral cat Felis catus, and a mosaic of closed and open foraging patches, allowing reliable assessment of spatio-temporal change in predation risk. We investigated the way such a change triggered individual prey decisions on where, when and how to perform routine activities. Results Rabbit presence and behavior were recorded both day and night in patches with similar foraging characteristics, but contrasted in terms of openness. Cats, individually recognizable, were more active at night and in closed patches, in line with their expected higher hunting success in those conditions. Accordingly, rabbits avoided using closed patches at night and increased their vigilance if they did. Both day and night, rabbits increased their use of closed patches as compared to open patches in windy conditions, thereby probably reducing the thermoregulatory costs expected under such harsh environmental conditions. Conclusions Overall, our data map the landscape of fear in this study system and indicate that prey habitat use and vigilance complement each other. Solely focusing on one or the other tactic may lead to erroneous conclusions regarding the way predation risk triggers prey decisions. Finally, future studies should investigate inter-individual variability in the relative use of these different types of complementary behavioral responses to perceived risk, along with the determinants and outcomes of such tactics.
... Alarm calls moreover elicited stronger responses when heard from a closer distance, again suggesting adaptive adjustment to heightened predation risk. Finally, stronger responses under windy conditions can likewise be explained as an adaptation to increased risk of predation [49]. Ungulates are known to increase group size and seek safe habitats as antipredator precautions under windy conditions where their ability to detect predators decreases [50]. ...
Article
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Heterospecific alarm calls may provide crucial survival benefits shaping animal behaviour. Multispecies studies can disentangle the relative importance of the various processes determining these benefits, but previous studies have included too few species for alternative hypotheses to be tested quantitatively in a comprehensive analysis. In a community-wide study of African savannah herbivores, we here, for the first time to our knowledge, partition alarm responses according to distinct aspects of the signaller–receiver relationship and thereby uncover the impact of several concurrent adaptive and non-adaptive processes. Stronger responses were found to callers who were vulnerable to similar predators and who were more consistent in denoting the presence of predators of the receiver. Moreover, alarm calls resembling those of conspecifics elicited stronger responses, pointing to sensory constraints, and increased responsiveness to more abundant callers indicated a role of learning. Finally, responses were stronger in risky environments. Our findings suggest that mammals can respond adaptively to variation in the information provided by heterospecific callers but within the constraints imposed by a sensory bias towards conspecific calls and reduced learning of less familiar calls. The study thereby provides new insights central to understanding the ecological consequences of interspecific communication networks in natural communities.
... In addition, it took the birds twice as long to successfully capture caterpillars on wind-exposed plants than on non-exposed controls. Great tits are visual foragers (Houston, Krebs, & Erichsen, 1980), and although we observed the birds visiting both wind-exposed and still plants during foraging, they probably have difficulty establishing a firm search image for their prey on wind-exposed plants that are in motion (Cherry & Barton, 2017). In this study, we investigated the effect of wind in a choice situation which may not realistically reflect wind conditions experienced in the field. ...
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1.Wind is an important abiotic factor that influences an array of biological processes, but it is rarely considered in studies on plant‐herbivore interactions. 2.Here, we tested whether wind exposure could directly or indirectly affect the performance of two insect herbivores, Plutella xylostella and Pieris brassicae, feeding on Brassica nigra plants. 3.In a greenhouse study using a factorial design, B. nigra plants were exposed to different wind regimes generated by fans before and after caterpillars were introduced on plants in an attempt to separate the effects of direct and indirect wind exposure on herbivores. 4.Wind exposure delayed flowering, decreased plant height and increased leaf concentrations of amino acids and glucosinolates. 5.Plant‐mediated effects of wind on herbivores, i.e., effects of exposure of plants to wind prior to herbivore feeding, were generally small. However, development time of both herbivores was extended and adult body mass of P. xylostella was reduced when they were directly exposed to wind. By contrast, wind‐exposed adult P. brassicae butterflies were significantly larger, revealing a trade‐off between development time and adult size. 6.Based on these results, we conducted a behavioral experiment to study preference by an avian predator, the Great Tit (Parus major) for last instar P. brassicae caterpillars on plants that were exposed to either control (no wind) or wind (fan‐exposed) treatments. Tits captured significantly more caterpillars on still than on wind‐exposed plants. 7.Our results suggest that P. brassicae caterpillars are able to perceive the abiotic environment and to trade off the costs of extended development time against the benefits of increased size depending on the perceived risk of predation mediated by wind exposure. Such adaptive phenotypic plasticity in insects has not yet been described in response to wind exposure. This article is protected by copyright. All rights reserved.
... This may be particularly true in our study as most deer that embarked upon excursions moved to pine forests and hardwood swamps, areas associated with Florida panthers [84,85]. However, it is possible that predation risk decreased temporarily owing to storm conditions [86], or the risk imposed by the storm simply outweighed the risk of predation. ...
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Efforts to understand population dynamics and identify high-quality habitat require information about spatial variation in demographic parameters. However, estimating demographic parameters typically requires labor-intensive capture-recapture methods that are difficult to implement over large spatial extents. Spatially explicit integrated population models (IPMs) provide a solution by accommodating spatial capture-recapture (SCR) data collected at a small number of sites with survey data that may be collected over a much larger extent. We extended the spatial IPM framework to include a spatio-Temporal point process model for recruitment, and we applied the model to 4 yr of SCR and distance-sampling data on Canada Warblers (Cardellina canadensis) near the southern extent of the species' breeding range in North Carolina, USA, where climate change is predicted to cause population declines and distributional shifts toward higher elevations. To characterize spatial variation in demographic parameters over the climate gradient in our study area, we modeled density, survival, and per capita recruitment as functions of elevation. We used a male-only model because males comprised >90% of our point-count detections. Apparent survival was low but increased with elevation, from 0.040 (95% credible interval CI: 0.0032-0.12) at 900 m to 0.29 (95% CI: 0.16-0.42) at 1,500 m. Recruitment was not strongly associated with elevation, yet density varied greatly, from <0.03 males ha⁻¹ below 1,000 m to >0.2 males ha⁻¹ above 1,400 m. Point estimates of population growth rate were <1 at all elevations, but 95% CIs included 1. Additional research is needed to assess the possibility of a long-Term decline and to examine the effects of abiotic variables and biotic interactions on the demographic parameters influencing the species' distribution. The modeling framework developed here provides a platform for addressing these issues and advancing knowledge about spatial demography and population dynamics.
... Odor cues are also transported as filamentous plumes by turbulent air flow in terrestrial habitats, which affects the spatial and temporal distribution of chemical signals (Koehl 2006). Thus, wind may affect chemoperception of predators by prey while also imposing physical limitations on walking and flying, which could inhibit prey ability to respond to predators (Cherry and Barton 2017). Mechanosensory detection, which is important in predator detection for arthropod prey in both aquatic and terrestrial habitats (Casas and Dangles 2010), can be hindered in high flow environments due to decreased signalto-noise ratio (Robinson et al. 2007). ...
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Predators influence communities through either consuming prey (consumptive effects, CEs) or altering prey traits (non-consumptive effects, NCEs), which has cascading effects on lower trophic levels. CEs are well known to decrease in physically stressful environments, but NCEs may be reduced at physically benign levels that affect the ability of prey to detect and respond to predators (i.e., sensory stress). We investigated the influence of physical and sensory stressors created by spatial and temporal differences in tidal flow on predator controls in a tritrophic system. We estimated mud crab reactive ranges to blue crab NCEs by evaluating mud crab CEs on juvenile oysters at different distances away from caged blue crabs across flow conditions. Mud crab reactive ranges were large at lower physical and sensory stress levels and blue crabs had a positive cascading effect on oyster survival. Blue crab NCEs were not important at higher flow conditions. Oyster survival was a complicated function of both types of stressors. Physical stress (i.e., current speed) had a positive effect on oyster survival by physically limiting mud crab CEs at high current speeds. Sensory stress (i.e., turbulence) interfered with the propagation of blue crab chemical cues used by mud crabs for predator detection, which removed blue crab NCEs. Mud crab CEs increased as a result and had a negative effect on oyster survival in turbulent conditions. Thus, environmental properties, such as fluid flow, can inflict physical and sensory stressors that have distinct effects on basal prey performance through impacts on different predator effects.
... Moreover, we encourage scientists to not only consider the effects of nighttime-driven climate warming, but how those warming effects interact with other aspects of climate change. Most climate change studies focus on temperature, with significantly fewer studies of the effects of altered atmosphere and soil chemistry [44], changing precipitation and snow regimes [45], changing wind speed [46,47] or the many other components of global change [6,48]. However, those studies that have examined multiple factors repeatedly report unexpected effects. ...
Article
Mean increases in temperatures associated with climate change are largely driven by increases in minimum (nighttime) temperatures; however, most climate change studies disproportionately increase maximum (daytime) temperatures. We review current literature to compare the potential effects of increasing daytime and nighttime temperatures on insects and their interactions within ecological communities. Although few studies have explicitly addressed the effects of nighttime warming, we draw from broader literature on how insects are affected by temperature to identify possible mechanisms that the timing (day or night) of warming may affect insects. Specifically, we discuss daily temperature variation, thermal performance curves, behavior and activity patterns, nighttime recovery from hot days, and bottom-up effects mediated by plants. While limited, the existing evidence suggests nighttime and daytime warming can have different effects, and thus we encourage scientists to use the most realistic warming treatments possible to truly understand how insects and their communities will be affected by climate change.
... In this study, we examined only the effect of temperature on biological control and trophic cascades within two management approaches. However, climate change affects other environmental conditions in addition to temperature, including changes in precipitation (Penczykowski et al. 2017), wind (Cherry and Barton 2017), and other factors. Studies on multiple, interacting climate change factors are few (Rosenblatt and Schmitz 2014;Gunderson et al. 2016;Rosenblatt et al. 2016,) but are critical if we are to develop a mechanistic, predictive understanding of climate change effects. ...
Article
Synopsis: Studies have shown that organically farmed fields promote natural predator populations and often have lower pest populations than conventional fields, due to a combination of increased predation pressure and greater plant resistance to pest damage. It is unknown how pest populations and predator efficacy may respond in these farming systems as global temperatures increase. To test these questions, we placed enclosures in eight alfalfa fields farmed using conventional (n = 4) or organic (n = 4) practices for 25 years. We stocked enclosures with pea aphids and 0, 2, or 4 predaceous ladybeetles. Half of the enclosures per field were then either left at ambient temperature or plastic-wrapped to warm them by 2 °C. Aphid abundances were similar in conventional and organic fields under ambient conditions, but were significantly more abundant in conventional than in organic fields when enclosures were warmed. Predator efficacy was reduced under low predator abundance (Hippodamia convergens = 2) in conventional fields under warming conditions; predation strength in organic fields was unaffected by warming. Alfalfa biomass increased with increased predators in all farming and temperature treatments. Our study suggests that biological control may be more easily maintained in organic than in conventional systems as global temperature increases.
... The presence of this bias in the literature motivated the special issue, Diverse effects of climate change on ecological communities. These papers review some of the most understudied aspects of climate change (Fig. 2), including ocean acidification (Ghedini and Connell 2017), phenology of sea ice (Post, 2017), changes in soil salinity (Harmon and Daigh, 2017), altered patterns of snow (Penczykowski et al., 2017) and reduced wind speeds, which are otherwise known as "global stilling" (Cherry and Barton, 2017). Additionally, Rosenblatt et al. (2017) model the effects of multiple changing variables (temperature, CO 2 , and water availability) on tri-trophic interactions. ...
... Large numbers of small-and medium-sized waders rely on inland natural wetlands to replenish their energy stores during their migrations (Verkuil et al., 1993). In these non-tidal wetlands, wind significantly affects the predator-prey relationship by altering detection or locomotion, and consequently, the foraging habitat or microhabitat selection patterns (Verkuil et al., 1993;Cherry and Barton, 2017). The main food supply for waders is aquatic invertebrates, which can be detected and captured visually or using tactile sensibility (Piersma et al., 1996). ...
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We aimed to identify the effects of the direction and wind speed on feeding habitat selection of wintering dunlins and little stints in an inland lake of the Iberian Peninsula. Feeding habitat (muddy surface or shallow water) and location in the lake with respect to wind direction (windward and leeward) of feeding flocks of both species were assessed on days with different wind speed (light or strong). We also performed visual counts of potential prey items (zooplankton) in mud and water habitats. In light wind conditions, wader flocks mostly selected the shallow water on the lake’s leeward shore. On the contrary, in strong wind conditions, the birds tended to forage on the windward shore, with a similar frequency in mud and shallow water habitats. The abundance of prey items in the mud and water column varied according to wind conditions, being higher in the sites preferred by waders. Our findings advance knowledge on how small–sized waders cope with environmental dynamics of wind in non–tidal lakes.
... In terrestrial environments, climate change can alter wind speeds (Young et al., 2011), and altered wind speed patterns can influence migratory success in birds (Nourani et al., 2017). Wind speed patterns can also disrupt predator-prey interaction by physically disturbing and dislodging individu-als and by disrupting locomotion (Cherry and Barton, 2017). The terrestrial environment, including wind speed and temperature, can influence the energetic cost of transport (Chappell et al., 2004;Halsey, 2016), which is a function of running kinematics (Kram and Taylor, 1990). ...
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Anthropogenic climate change induces unprecedented variability in a broad range of environmental parameters. These changes will impact material properties and animal biomechanics, thereby affecting animal performance and persistence of populations. Climate change implies warming at the global level, and it may be accompanied by altered wind speeds, wave action, ocean circulation, acidification as well as increased frequency of hypoxic events. Together, these environmental drivers affect muscle function and neural control and thereby movement of animals such as bird migration and schooling behaviour of fish. Altered environmental conditions will also modify material properties of animals. For example, ocean acidification, particularly when coupled with increased temperatures, compromises calcified shells and skeletons of marine invertebrates and byssal threads of mussels. These biomechanical consequences can lead to population declines and disintegration of habitats. Integrating biomechanical research with ecology is instrumental in predicting the future responses of natural systems to climate change and the consequences for ecosystem services such as fisheries and ecotourism.
... Abiotic forces (e.g., fire, tidal cycles, and wind) along ecotones may also influence habitat structure, and how organisms move into/out of and across habitat boundaries. For instance, higher wind speeds have been shown to disturb habitat structure along the edge of habitats decreasing the efficiency of predators, jostling tree branches decreasing prey visibility, and altering olfactory cues (Cherry and Barton 2017). Within salt marsh habitats, the regular inundation by saltwater due to tides can alter plant characteristics and the presence of certain types of plant species. ...
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Over heterogeneous landscapes, organisms and energy move across ecological boundaries and this can have profound effects on overall ecosystem functioning. Both abiotic and biotic factors along habitat boundaries may facilitate or impede key species interactions that drive these energy flows—especially along the land–sea interface. We synthesized the literature detailing estuarine fish diets and habitat characteristics of salt marshes from U.S. East and Gulf coasts to determine patterns and drivers of cross‐boundary trophic transfers at the land–sea interface. Notably, marsh‐platform species (i.e., killifishes, fiddler crabs) appear virtually absent in the diets of transient estuarine fishes in the Gulf of Mexico, while along the South Atlantic and Mid‐Atlantic Bights, marsh‐platform species appear regularly in the diets of many transient estuarine fishes. Tidal amplitude varied across these three biogeographic regions and likely regulates the availability of marsh‐platform species to transient estuarine fishes via both access to the marsh surface for marine predators and emergence of marsh‐resident prey into the adjacent estuary (i.e., higher tidal amplitude increases predator–prey encounter rates). Surprisingly, marsh shoot density was positively correlated with the presence of marsh‐platform species in the diet, but this pattern appears to be mediated by increased tidal amplitude, suggesting the mode and periodicity of abiotic cycles drive diet structure of transient estuarine fishes more so than local habitat structural complexity. Subsequently, these processes likely influence the degree to which “trophic relay” moves energy from the marsh toward the open estuary. Understanding the dynamics that determine energy flows, spatial subsidies, and ultimately, ecosystem‐level productivity, is essential for implementation of holistic ecosystem‐based approaches to conserve and manage complex landscape mosaics.
... Environmental fluctuations have the potential to affect not only individuals and populations, but also higher (community) levels through species interactions such as competition and predator-prey relationships (Nilsen et al., 2009;Cherry and Barton, 2017;Turner et al., 2017). For one, abiotic changes alter species distribution and consequently species overlap due to habitats becoming more or less accessible or favorable for survival. ...
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Animals often face changing environments, and behavioral flexibility allows them to rapidly and adaptively respond to abiotic factors that vary more or less regularly. However, abiotic factors that affect prey species do not necessarily affect their predators. Still, the prey’s response might affect the predator indirectly, yet evidence from the wild for such a classical bottom-up effect of abiotic factors shaping several trophic levels remains sparse. In many aquatic environments, daily changes in oxygen concentrations occur frequently. When oxygen levels drop to hypoxic levels, many fishes respond with aquatic surface respiration (ASR), during which they obtain oxygen by skimming the upper, oxygenated surface layer. By increasing time at the surface, fish become more vulnerable to fish-eating birds. We explored these cascading effects in a sulfidic spring system that harbors the endemic sulphur molly (Poecilia sulphuraria) as prey species and several fish-eating bird species. Sulfide-rich springs pose harsh conditions as hydrogen sulfide (H2S) is lethal to most metazoans and reduces dissolved oxygen (DO). Field sampling during three daytimes indicated that water temperatures rose from morning to (after)noon, resulting in the already low DO levels to decrease further, while H2S levels showed no diurnal changes. The drop in DO levels was associated with a decrease in time spent diving in sulphur mollies, which corresponded with an increase in ASR. Interestingly, the laboratory-estimated threshold at which the majority of sulphur mollies initiate ASR (ASR50: <1.7 mg/L DO) was independent of temperature and this value was exceeded daily when hypoxic stress became more severe toward noon. As fish performed ASR, large aggregations built up at the water surface over the course of the day. As a possible consequence of fish spending more time at the surface, we found high activity levels of fish-eating birds at noon and in the afternoon. Our study reveals that daily fluctuations in water’s oxygen levels have the potential to alter predator-prey interactions profoundly and thus highlights the joined actions of abiotic and biotic factors shaping the evolution of a prey species.
... The number of flowers per plant did not affect any of the dependent variables considered; this might seem quite surprising, as other studies highlighted its positive effect on flower visits [107][108][109]. However, owing to the number of flowers in the plants studied (always ≥ 20), we could not detect whether plants with fewer flowers would receive fewer visits; indeed, the positive effect of the number of flowers on the number of visits per plant might be more pronounced for low flower numbers and less marked for plants with many flowers [110]. Regarding the daily pattern of flower-visiting arthropod activity, we observed a significant effect of quadratic time on both flower visitors' presence and abundance but not on their diversity. ...
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In mountain ecosystems, climate change can cause spatiotemporal shifts, impacting the composition of communities and altering fundamental biotic interactions, such as those involving flower-visiting arthropods. On of the main problems in assessing the effects of climate change on arthropods in these environments is the lack of baseline data. In particular, the arthropod communities on early flowering high-altitude plants are poorly investigated, although the early season is a critical moment for possible mismatches. In this study, we characterised the flower-visiting arthropod community on the early flowering high-altitude Alpine plant, Androsace brevis (Primulaceae). In addition, we tested the effect of abiotic factors (temperature and wind speed) and other variables (time, i.e., hour of the day, and number of flowers per plant) on the occurrence, abundance, and diversity of this community. A. brevis is a vulnerable endemic species growing in the Central Alps above 2000 m asl and flowering for a very short period immediately after snowmelt, thus representing a possible focal plant for arthropods in this particular moment of the season. Diptera and Hymenoptera were the main flower visitors, and three major features of the community emerged: an evident predominance of anthomyiid flies among Diptera, a rare presence of bees, and a relevant share of parasitoid wasps. Temperature and time (hour of the day), but not wind speed and number of flowers per plant, affected the flower visitors’ activity. Our study contributes to (1) defining the composition of high-altitude Alpine flower-visiting arthropod communities in the early season, (2) establishing how these communities are affected by environmental variables, and (3) setting the stage for future evaluation of climate change effects on flower-visiting arthropods in high-altitude environments in the early season.
... The effect of wind on migrating insects may be even stronger as some depend on the wind for successful arrival at their destination (Chapman et al., 2002;Stefanescu et al., 2007). Wind usually impairs the ability of predators to recognize prey but also vice versa, leading either to an increase or a decrease in predation risk (reviewed in Cherry & Barton, 2017). Wind can affect the decision of which foraging mode to use, that is to actively search for prey or ambush it. ...
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Animals require a set of abiotic conditions to survive and reproduce. When one of these requirements is not met, the animal's performance is impaired. The most often studied abiotic factor is temperature but less is known on other such factors. We examined, here, the effect of wind on the hunting performance of pit-building predators, insect larvae that dig pit traps in loose soil to hunt arthropod prey. We used wormlions (Diptera: Vermileonidae) as a case study. Pit-building predators depend on their immediate environment for efficient pit construction and maintenance. For example, they require dry suitable substrate (loose soil) comprised of particles of a specific size range. Because wind blows loose soil and impairs pit construction and maintenance, we expected strong negative effects of wind on pit design and hunting success. Wind destroyed both artificial pit traps and wormlion-dug pits by moving sand into the pits and reducing their slopes-an important parameter of pits in terms of prey capture. Wormlions also attempted less frequently to attack the prey when the wind was blowing compared to the control and, among the wormlions responding, such response took place later, allowing the prey to escape. We expected wormlions to relocate away when exposed to the wind, but this did not hold true. This result is in line with the generally low relo-cation rate in wormlions. We suggest that wind has strong negative effects on the performance of pit builders in nature. Sites that provide at least partial protection from wind should be preferred for pit establishment.
... Biotic and abiotic environmental factors can impact the behavior and ecology of animal populations; however, the specific environmental factors that modulate the interactions between species are relatively unknown (Kordas et al. 2011;Imperio et al. 2012;Cherry and Barton 2017). Under the current scenario of global environmental change, understanding the size and direction of environmental effects on animal behavior is critical to know how species will interact in the ecosystems of the future. ...
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Interspecific interactions are key drivers of individual and population level fitness in a wide range of animals. However, in marine ecosystems, it is relatively unknown which biotic and abiotic factors impact behavioral interactions between competing species. We assessed the impact of weather, marine productivity and population structure on the behavioral agonistic interactions between South American fur seals (SAFS), Arctocephalus australis, and South American sea lions (SASL), Otaria byronia, in a breeding colony of SAFS. We hypothesized that agonistic interactions between SAFSs and SASLs respond to biotic and abiotic factors such as SAFS population structure, marine productivity and weather. We found that SASL and SAFS interactions almost always resulted in negative impacts on the social structure or reproductive success of the SAFS colony. SASL adult males initiated stampedes of SAFS and/or abducted and predated SAFS pups. Adult SAFS males abundance and severe weather events were negatively correlated with agonistic interactions between species. However, proxies for lower marine productivity such as higher sea surface temperature and lower catches of demerso-pelagic fish were the most important predictors of more frequent agonistic interactions between SAFS and SASL. Under the current scenario of decline in marine biomass due to global climate change and overfishing, agonistic interactions between competing marine predators could increase and exacerbate the negative impacts of environmental change in these species.
... Wind speed has been shown to have contrasting effects on animal vigilance and escape behavior, from no effect to marked effects depending on the species and taxa (e.g., no effect: birds; Clucas & Marzluff, 2011, Nordell et al., 2017, Petrelli et al., 2017reptiles;McGowan et al., 2014;wind effects: birds;Reynolds et al., 2020;mammals;Wolf & Croft, 2010). Increased wind speed has been shown in 17 of 18 studies to decrease an animal's ability to detect an approaching predator by masking sounds, smells, and visual cues (Cherry & Barton, 2017). Wind may also be a source of distraction (Chan et al., 2010;Tätte et al., 2019), leading to delayed detection of approaching predators. ...
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Alert distance (AD) and flight initiation distance (FID) are popular measures used to explore the reaction of prey to approaching predators, and thus the economics underlying optimal escape strategies. AD likely mirrors the effort invested into vigilance, while FID provides an estimate of the perceived risk of an approaching threat. Although individual variation in AD and FID is influenced by environmental factors such as variation in predation pressure and human disturbance, the repeatabilities of these traits (especially AD), and therefore their designation as personality traits, remain under-investigated. Here, we studied the repeatability of AD, FID, and the decision to flee in a flightless, ground-breeding seabird, the king penguin (Aptenodytes patagonicus). A single experimenter approached three times over three consecutive days 47 incubating king penguins from two different colonies with varying human disturbance levels. We explored the effects of weather, time of day, and approach speed of the experimenter on these behaviors. Weather had an effect on all three behaviors. In warm, sunny weather AD increased. In rainy, windy weather birds were more likely to flee, but waited longer before initiating flight. Faster approach speeds between AD and FID increased FID. Weather conditions and speed of approach affected repeatability estimates, highlighting the need to consider external sources of variation when refining such estimates. FID and the decision to flee were significantly and moderately repeatable (r = 0.26 and 0.57, respectively), while AD was not. There was no evidence of behavioral habituation or sensitization in either colony.
... For example, by making use of high vegetation density during ambush behaviour, lions (Panthera leo) are more likely to successfully make a kill, even in locations with low prey abundance (Davies et al. 2016). Reduction in wind speeds can also affect predator-prey interactions by modifying species detection, locomotion and physical disturbance (Cherry and Barton 2017). In aquatic habitats, environmental gradients such as temperature, salinity, dissolved oxygen and barometric pressure, affect the patterns of space use of many predators (Block et al. 2011;Schlaff et al. 2014). ...
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Globally, marine animal distributions are shifting in response to a changing climate. These shifts are usually considered at the species level, but individuals are likely to differ in how they respond to the changing conditions. Here, we investigate how movement behaviour and, therefore, redistribution, would differ by sex and maturation class in a wide-ranging marine predator. We tracked 115 tiger sharks (Galeocerdo cuvier) from 2002 to 2020 and forecast class-specific distributions through to 2030, including environmental factors and predicted occurrence of potential prey. Generalised Linear and Additive Models revealed that water temperature change, particularly at higher latitudes, was the factor most associated with shark movements. Females dispersed southwards during periods of warming temperatures, and while juvenile females preferred a narrow thermal range between 22 and 23 °C, adult female and juvenile male presence was correlated with either lower (< 22 °C) or higher (> 23 °C) temperatures. During La Niña, sharks moved towards higher latitudes and used shallower isobaths. Inclusion of predicted distribution of their putative prey significantly improved projections of suitable habitats for all shark classes, compared to simpler models using temperature alone. Tiger shark range off the east coast of Australia is predicted to extend ~ 3.5° south towards the east coast of Tasmania, particularly for juvenile males. Our framework highlights the importance of combining long-term movement data with multi-factor habitat projections to identify heterogeneity within species when predicting consequences of climate change. Recognising intraspecific variability will improve conservation and management strategies and help anticipate broader ecosystem consequences of species redistribution due to ocean warming.
... In South Africa's thicket biome, for instance, lions (Panthera leo) choose their kill sites based on higher vegetation density which might facilitate predator concealment and affect the ability of prey to escape from an attack (Davies et al. 2016). Prey abundance and distribution is an important factor influencing the movements of marine predators (Taylor et al. 2018a), with foraging success directly related to particular environmental conditions (Cherry and Barton 2017). For example, white sharks (Carcharodon carcharias) are seasonally present in False Bay, South Africa, to prey on Cape fur seals (Arctocephalus pusillus) and rely on low-light periods to increase attack success rate (Hammerschlag et al. 2006). ...
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Greater Sydney is the largest coastal city in Australia and is where bull sharks (Carcharhinus leucas) are present every summer and autumn. A decade of acoustic telemetry data was used to identify drivers of space use for bull sharks and their potential prey, according to standardised 6-h intervals using dynamic Brownian bridge movement models. Influences of environmental, physical, and biological variables on the areas of space use, location, and predator-prey co-occurrence were investigated with generalised additive mixed models. Rainfall in the catchment affected space use for all animals (i.e. teleost species and both sexes of sharks), with varying temporal responses. Male sharks responded most promptly to high rainfall moving upstream in < 1 day, followed by teleosts (2 to 7 days), and female bull sharks after 4 days. Environmental luminosity affected male shark dispersal and space use, possibly indicating use of visual cues for foraging. Physical characteristics of habitat were important factors driving spatial overlaps between predator and prey in estuarine areas. In sandy embayments < 10-m deep, males and female bull sharks overlapped with different species, whereas males and silver trevally (Pseudocaranx georgianus) co-occurred in deep holes (> 30 m). Shark size influenced overlap between sexes, with smaller females less likely to co-occur with larger males (~ 50 cm). Variability in space use suggests spatial segregation by sex and size in bull sharks, with individuals targeting similar prey, yet either in different areas or at different times, ultimately enabling them to exploit different resources when in the same habitats.
... Other climatic factors may, however, also be influential in determining individual species distributions and, as a result, community characteristics (Barton, 2017;Cherry & Barton, 2017;Maclean, 2020). Therefore, to improve the quality of the predictions of the ecological impacts of climate change, it is important to consider a more comprehensive set of climatic variables that directly affect plant performance (Gardner et al., 2019). ...
Article
1. The effects of temperature and precipitation, and the impacts of changes in these climatic conditions, on plant communities have been investigated extensively. The roles of other climatic factors are, however, comparatively poorly understood, despite potentially also strongly structuring community patterns. Wind, for example, is seldom considered when forecasting species responses to climate change, despite having direct physiological and mechanical impacts on plants. It is, therefore, important to understand the magnitude of potential impacts of changing wind conditions on plant communities, particularly given that wind patterns are shifting globally. 2. Here, we examine the relationship between wind stress (i.e. a combination of wind exposure and wind speed) and species richness, vegetation cover and community composition using fine‐scale, field‐collected data from 1440 quadrats in a windy sub‐Antarctic environment. 3. Wind stress was consistently a strong predictor of all three community characteristics, even after accounting for other potentially ecophysiologically important variables, including pH, potential direct incident solar radiation, winter and summer soil temperature, soil moisture, soil depth, and rock cover. Plant species richness peaked at intermediate wind stress, and vegetation cover was highest in plots with the greatest wind stress. Community composition was also related to wind stress, and, after the influence of soil moisture and pH, had a similar strength of effect as winter soil temperature. 4. Synthesis: Wind conditions are, therefore, clearly related to plant community characteristics in this ecosystem that experiences chronic winds. Based on these findings, wind conditions require greater attention when examining environment‐community relationships, and changing wind patterns should be explicitly considered in climate change impact predictions.
... Thus, FID would be expected to increase to compensate for this risky behaviour. Additionally, increased wind may also directly affect predation risk as higher wind speeds can have a positive effect on the manoeuvrability of vertebrate aerial predators and increase predators' dietary requirements (Hilton et al. 1999;Cherry and Barton 2017). ...
Article
ContextThe disruption of normal activities by humans (i.e. ‘anthropogenic disturbance’) can have important behavioural, physiological and population effects on coastal birds. These negative effects include increased vigilance, increased energy expenditure and reduced nesting success. To overcome this, separation distances (e.g. buffers and setbacks) are often used to separate threatening stimuli, such as humans, from wildlife. However, in most instances the determination of separation distances are based on little empirical information. This is particularly true for Africa, which supports huge populations of Palearctic migrant shorebirds. AimTo determine suitable separation distances that will reduce anthropogenic disturbance to the coastal bird community at West Coast National Park, South Africa. Methods The distance at which a behavioural response (i.e. flight initiation distance, FID) occurred among 15 common coastal bird species when presented with an approaching human was measured. Linear mixed-effects models were used to determine the relationship between FID and body size, migratory status, intraspecific flock size, flock species richness, foraging behaviour and several environmental covariates. Key resultsBody mass was significantly and positively correlated with FID, indicating that larger birds are more sensitive to the anthropogenic stimulus. Furthermore, it was shown that migratory birds had longer FIDs, suggesting that they are less risk tolerant compared with resident birds. The distance at which the approach was initiated (i.e. the start distance, SD) was also significantly and positively correlated with FID, supporting the hypothesis that birds will flush early to avoid the potential negative consequences of fleeing too late. Finally, there was a novel significant effect of increasing wind speed on increasing FID, suggesting a thermoregulatory trade-off. There was no effect of foraging behaviour, flock size or flock composition on FID. Conclusion Based on these data, buffer distances for tidal habitats at West Coast National Park should be set at ~170 m. ImplicationsImproved understanding of FID, and the morphological and behavioural predictors thereof, will enable West Coast National Park and other protected areas to designate separation distances or buffer zones that reduce the negative effects of anthropogenic disturbance on shorebird communities.
... At finer spatial scales, deer movements within the wildland-urban interface increased at night, and they selected greater levels of nightlight. Cougars are primarily nocturnal hunters and so the additional deer activity at night, along with a potentially diminished ability to perceive predator cues associated with elevated nightlight (Gaston et al. 2017) and other aspects of the urban environment (Cherry and Barton 2017), may put deer at greater risk. However, the nutritional benefits of these environments (we found deer located in the urban interface at locations with 23% greater average vegetative greenness) to deer may outweigh the risks, and selection for nightlight during these movements may create a predator shield in areas with the highest nightlight radiance. ...
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Artificial nightlight is increasingly recognized as an important environmental disturbance that influences the habitats and fitness of numerous species. However, its effects on wide-ranging vertebrates and their interactions remain unclear. Light pollution has the potential to amplify land-use change, and as such, answering the question of how this sensory stimulant affects behavior and habitat use of species valued for their ecological roles and economic impacts is critical for conservation and land-use planning. Here, we combined satellite-derived estimates of light pollution, with GPS-data from cougars Puma concolor (n = 56), mule deer Odocoileus hemionus (n = 263) and locations of cougar-killed deer (n = 1562 carcasses), to assess the effects of light exposure on mammal behavior and predator-prey relationships across wildland-urban gradients in the southwestern United States. Our results indicate that deer used the anthropogenic environments to access forage and were more active at night than their wildland con-specifics. Despite higher nightlight levels, cougars killed deer at the wildland-urban interface, but hunted them in the relatively darkest locations. Light had the greatest effect of all covariates on where cougars killed deer at the wildland-urban interface. Both species exhibited functional responses to light pollution at fine scales; individual cougars and deer with less light exposure increasingly avoided illuminated areas when exposed to greater radiance, whereas deer living in the wildland-urban interface selected elevated light levels. We conclude that integrating estimates of light pollution into ecological studies provides crucial insights into how the dynamic human footprint can alter animal behavior and ecosystem function across spatial scales.
... The daily decisions and trade-offs animals make are not limited to balancing resource acquisition against the risk of predation and competition, but they are also influenced by environmental conditions and human activity (Beauchamp, 2015). For example, stronger wind speeds may result in the elevated vigilance of prey animals as it has been shown to negatively affect their ability to detect and evade predators (Cherry & Barton, 2017), while animals which rely on flight to flee predators often show lower levels of responsiveness with increasing wind speed (Carr & Lima, 2010), possibly because it is more physically demanding and riskier to take-off in strong winds. Likewise, trade-offs have been demonstrated between the physiological costs of thermoregulation and vigilance, suggesting that vigilance is more energetically costly at lower temperatures (Pravosudov & Grubb, 1995). ...
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Vigilance is a costly behaviour but it enables animals to detect and avoid threats of predation and intraspecific competition. To compensate for the increased risk while sleeping, many bird species have evolved eye‐blinking strategies called peeking, which allows vigilance to persist in a sleep‐like state. However, the drivers of vigilance behaviour during sleep have rarely been explored. We investigated how social factors, anthropogenic disturbance and environmental conditions affected the sleep‐vigilance trade‐off in the Eurasian oystercatcher (Haematopus ostralegus). Data were collected on the frequency, total duration and average duration of peeking at two locations on the Menai Strait, North Wales. Our results reveal that exposure to anthropogenic disturbance, particularly the presence of people exercising dogs, led to an increase in vigilance duration and reduced time sleeping, while increasing boat traffic resulted in elevated levels of peek frequency, but the overall duration of vigilance was in fact reduced. Furthermore, oystercatchers adjust their vigilance behaviour according to social context, with reduced levels of individual vigilance when a greater number of animals were present. However, if surrounding neighbours were awake – then the observed animal was more likely to be alert, demonstrating the importance of monitoring the behaviour of conspecifics. Likewise, the temperature and wind speed influenced vigilance with elevated levels of peek frequency observed in warmer and windier conditions. Oystercatchers are able to make fine‐scale adjustments to their vigilance behaviour while asleep, which reduces the risk of external threats such as predators. Nevertheless, they are making these decisions against the backdrop of a finely balanced energy budget, particularly during the winter months. Increased levels of human activity and disturbance may elevate the costs of vigilance and ultimately have fitness implications for this species. We investigated how social factors, anthropogenic disturbance and environmental conditions affected the sleep–vigilance trade‐off in the Eurasian oystercatcher. Our results reveal that exposure to anthropogenic disturbance led to an increase in vigilance behaviour and reduced time sleeping, which may have fitness implications, particularly when resources are scarce and energy demand is high. Furthermore, oystercatchers are able to make fine‐scale adjustments to their vigilance behaviour according to social context (number and behaviour of neighbouring birds) and environmental conditions (temperature and wind speed).
... Wind speed was not included in the best model for all hunters and had opposite effects on hunter groups; daily harvest increased for non-residents and decreased for residents with increased wind speeds. Increased winds may improve harvest success by masking sound and improving predictability of how scent travels (Cherry and Barton 2017), two factors hunters commonly account for when in the field. A potential explanation for increased non-resident daily harvest may be related to professional guides' relatively high-level of experience who accompany most non-residents. ...
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Although extensive research has been conducted on a variety of factors that influence wildlife harvest rates, few studies have quantified the impact of weather on harvest success. As global warming continues to contribute to unprecedented changes in local weather regimes, particularly in arctic and alpine ecosystems, understanding how these changes impact human–wildlife interactions will become increasingly important and relevant for wildlife managers. Therefore, we used a long-term dataset (1999–2015) on Dall's sheep Ovis dalli dalli, an alpine species in Alaska, USA, as a case study to explore how changes in local daily weather has affected hunter harvest success. We used generalized linear mixed models to estimate relationships between daily harvest count and weather variables using three separate models; all hunters, resident hunters and non-resident hunters. Weather variables included daily mean relative humidity, precipitation, air temperature and wind speed. For our model including all hunters, which excluded wind, we estimated that a mean increase in relative humidity, precipitation and temperature from one day to the next resulted in an 11.7, 4.3 and 2.9% decrease in daily harvest, respectively. The effect of relative humidity influenced harvest count two to three times more than all other weather variables across models. This study contributes to a limited body of knowledge on quantifying the impact of weather on harvest success and about how changes in weather affect hunter and wildlife behavior. Advancing knowledge on how weather influences variation in harvest may facilitate effective strategies for adapting hunting regulations to meet harvest and population goals.
... turbulence) pose biomechanical challenges [9][10][11][12][13] that push manoeuvrability limits in flying insects [14] and can impose energetic costs on flight [15]. The mechanical and physiological challenges posed by wind may have important effects on insects' interactions with plants, including herbivory [16,17], and pollinator visitation and landing [18]. Wind also indirectly impacts flying insects by inducing plant movements [19], which can impose additional manoeuvrability challenges [14] In addition to biophysical challenges, wind disperses chemical cues and signals critical for interactions between insects (e.g. ...
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Wind is a critical factor in the ecology of pollinating insects such as bees. However, the role of wind in determining patterns of bee abundance and floral visitation rates across space and time is not well understood. Orchid bees are an important and diverse group of neotropical pollinators that harvest pollen, nectar and resin from plants. In addition, male orchid bees collect volatile scents that they store in special chambers in their hind legs, and for which the wind-based dispersal of odours may play a particularly crucial role. Here, we take advantage of this specialized scent foraging behaviour to study the effects of wind on orchid bee visitation at scent sources in a fragmented tropical forest ecosystem. Consistent with previous work, forest cover increased orchid bee visitation. In addition, we find that temporal changes in wind speed and turbulence increase visitation to scent stations within sites. These results suggest that the increased dispersal of attractive scents provided by wind and turbulence outweighs any biomechanical or energetic costs that might deter bees from foraging in these conditions. Overall, our results highlight the significance of wind in the ecology of these important pollinators in neotropical forests.
... * M. Sclafani ms332@cornell.edu 1 migration modes (Jonzén et al. 2011) and behavior can subsequently shape community structure and species coexistence (Hilborn 1975;Holt 1984). Predator movements, and foraging behavior and ability (Hammerschlag et al. 2006;Grigaltchik et al. 2012), can also be mediated by diel, seasonal or episodic environmental factors, including temperature (Sanford 2002), light intensity (Einfalt et al. 2012), atmospheric phenomena (Cherry and Barton 2017), turbidity (Lunt and Smee 2014), tidal exposure (Zamon 2001) and current velocity (Robinson et al. 2011). In general, these processes are less well known for marine taxa, especially in the field. ...
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Quantifying predator-prey interactions and gaining insights into predator behavior are crucial for optimizing restoration strategies; yet, such knowledge is often lacking for marine invertebrates. We examined potential impacts of predation by channeled ( Busycotypus canaliculatus ) and knobbed whelks ( Busycon carica ) on natural and planted populations of bay scallops in the Peconic Bays, New York, through laboratory and field investigations. Mean rates of predation by small channeled whelks were low: 0.06 and 0.005 scallops d ⁻¹ for adult and juvenile scallops; respective lab predation rates of small knobbed whelks on juvenile scallops were 24x higher. Channeled whelks usually did not damage shells of scallop prey (86%), but knobbed whelks typically notched the ventral shell margin (73%). In field plots where scallop densities were manipulated via removals/plantings, whelks consumed ~2% of ~19,100 planted juveniles; crabs and presumably finfish consumed over 40% in all trials overall. Acoustic telemetry revealed that tagged channeled whelks moved shorter distances and spent more time in plots planted with scallops versus those without scallops. Unexpectedly, whelks spent more time in low vs. high density plots, but consumed far more scallops in the latter. In trials without scallops, whelk movement rates were 5x higher, presumably due to increased exploratory behavior. Overall, whelks were most active during crepuscular hours and during periods of increasing wind speeds. Our results, combined with population abundance data, suggest that whelks (especially B. carica ) are drawn to high density scallop plantings and may be important causes of bay scallop mortality in the context of restoration efforts.
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A comprehensive intercomparison of historical wind speed trends over the contiguous United States is presented based on two observational data sets, four reanalysis data sets, and output from two regional climate models (RCMs). This research thus contributes to detection, quantification, and attribution of temporal trends in wind speeds within the historical/contemporary climate and provides an evaluation of the RCMs being used to develop future wind speed scenarios. Under the assumption that changes in wind climates are partly driven by variability and evolution of the global climate system, such changes should be manifest in direct observations, reanalysis products, and RCMs. However, there are substantial differences in temporal trends derived from observational wind speed data, reanalysis products, and RCMs. The two observational data sets both exhibit an overwhelming dominance of trends toward declining values of the 50th and 90th percentile and annual mean wind speeds, which is also the case for simulations conducted using MM5 with NCEP-2 boundary conditions. However, converse trends are seen in output from the North American Regional Reanalysis, other global reanalyses (NCEP-1 and ERA-40), and the Regional Spectral Model. Equally, the relationship between changing annual mean wind speed and interannual variability is not consistent among the different data sets. NCEP-1 and NARR exhibit some tendency toward declining (increasing) annual mean wind speeds being associated with decreased (increased) interannual variability, but this is not the case for the other data sets considered. Possible causes of the differences in temporal trends from the eight data sources analyzed are provided.
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