Landscape Of Fear Research Articles

Individual differences in risk‐taking affect foraging across different landscapes of fear

One of the strongest determinants of behavioural variation is the tradeoff between resource gain and safety. Although classical theory predicts optimal foraging under risk, empirical studies report large unexplained variation in behaviour. Intrinsic individual differences in risk‐taking behaviour might contribute to this variation. By repeatedly exposing individuals of a small mesopredator to different experimental landscapes of risks and resources, we tested 1) whether individuals adjust their foraging behaviour according to predictions of the general tradeoff between energy gain and predation avoidance and 2) whether individuals differ consistently and predictably from each other in how they solve this tradeoff. Wild‐caught individuals (n = 42) of the jumping spider Marpissa muscosa, were subjected to repeated release and open‐field tests to quantify among‐individual variation in boldness and activity. Subsequently, individuals were tested in four foraging tests that differed in risk level (white/dark background colour) and risk variation (constant risk/variable risk simulated by bird dummy overflights) and contained inaccessible but visually perceivable food patches. When exposed to a white background, individuals reduced some aspects of movement and foraging intensity, suggesting that the degree of camouflage serves as a proxy of perceived risk in these predators. Short pulses of acute predation risk, simulated by bird overflights, had only small effects on aspects of foraging behaviour. Notably, a significant part of variation in foraging was due to among‐individual differences across risk landscapes that are linked to consistent individual variation in activity, forming a behavioural syndrome. Our results demonstrate the importance of among‐individual differences in behaviour of animals that forage under different levels of perceived risk. Since these differences likely affect food‐web dynamics and have fitness consequences, future studies should explore the mechanisms that maintain the observed variation in natural populations.

The effects of red fox scent on winter activity patterns of suburban wildlife: evaluating predator-prey interactions and the importance of groundhog burrows in promoting biodiversity

During winter, prey species in suburban areas of the northeastern United States must consider trade-offs in maximizing survival while they are simultaneously constrained by predators and climatic conditions associated with winter such as snow and low temperatures. Many mammalian prey mitigate the physiological stress from the cold by taking refuge in burrows. Some have also developed olfactory sensitivity to predator scent cues as they attempt to avoid predation in the landscape of fear and co-evolutionary arms race between predators and prey. The Eastern cottontail (Sylvilagus floridanus) is one of these species that both uses burrows in winter and is sensitive to scents. However, despite the importance of cottontails in the diet of Red foxes (Vulpes vulpes), one of their major predators, little is known about scent cues that cottontails use to detect foxes. Eastern cottontails and other suburban wildlife that occupied burrows dug by Groundhogs near Ithaca, New York, USA were exposed to scent wicks treated with Red fox urine during the winter of 2017–2018 to determine if the frequency of burrow use would decrease because of a perceived heightened risk of predation. We observed no response to the predator odor by cottontails and the other burrow-utilizing species. This lack of a behavioral response by prey may be due to the attenuation of fear in suburban environments. A surprising variety of mammalian and avian taxa (n = 22) were recorded at burrows, including Striped skunks, mice, Domestic cats, Virginia opossums, Bobcats, White-tailed deer, Weasels, a Coyote, and a Gray fox. Surprisingly we did not observe a single Red fox, for whom intraspecific scent cues are also important. We also documented daily patterns of activity around burrows of the five most commonly observed taxa. Our investigation reveals that Groundhogs are notable ecosystem engineers whose burrows function as important landscape features and local hotspots of biodiversity during the winter in a suburban ecosystem.

Mixed-species groups of Serengeti grazers: a test of the stress gradient hypothesis.

Understanding the role of species interactions within communities is a central focus of ecology. A key challenge is to understand variation in species interactions along environmental gradients. The stress gradient hypothesis posits that positive interactions increase and competitive interactions decrease with increasing consumer pressure or environmental stress. This hypothesis has received extensive attention in plant community ecology, but only a handful of tests in animals. Furthermore, few empirical studies have examined multiple co‐occurring stressors. Here we test predictions of the stress gradient hypothesis using the occurrence of mixed‐species groups in six common grazing ungulate species within the Serengeti‐Mara ecosystem. We use mixed‐species groups as a proxy for potential positive interactions because they may enhance protection from predators or increase access to high‐quality forage. Alternatively, competition for resources may limit the formation of mixed‐species groups. Using more than 115,000 camera trap observations collected over 5 yr, we found that mixed‐species groups were more likely to occur in risky areas (i.e., areas closer to lion vantage points and in woodland habitat where lions hunt preferentially) and during time periods when resource levels were high. These results are consistent with the interpretation that stress from high predation risk may contribute to the formation of mixed‐species groups, but that competition for resources may prevent their formation when food availability is low. Our results are consistent with support for the stress gradient hypothesis in animals along a consumer pressure gradient while identifying the potential influence of a co‐occurring stressor, thus providing a link between research in plant community ecology on the stress gradient hypothesis, and research in animal ecology on trade‐offs between foraging and risk in landscapes of fear.

Effects of habitat and fish type and diet on the behavior of Daphnia

ABSTRACT Infochemical landscapes, also referred to as landscapes of fear, can strongly influence the distribution of organisms. Planktivore infochemicals alter zooplankton distribution; zooplankton avoid macrophytes in the absence of planktivorous fish and associate with macrophytes when planktivorous fish are present. It is unclear, however, how zooplankton respond to fish with different diets in the presence and absence of habitat. In a laboratory experiment, we evaluated avoidance of Daphnia pulex to 4 fish treatments including a fishless control, a piscivore (muskellunge [Esox musquinongy]) with a diet of planktivores, and a planktivore (bluegill [Lepomis macrochirus]) with either a diet of conspecific zooplankton or a diet of heterospecifics: terrestrial invertebrates (crickets [Acheta domesticus]). These treatments used presence and absence of macrophytes to evaluate whether macrophytes alter responses to these fish treatments. Relative to control treatments, D. pulex avoided bluegill fed D. pulex and did not avoid muskellunge or bluegill fed A. domsesticus. Macrophytes were avoided in all fish treatments. Consumption of D. pulex, which was concurrently evaluated for the 2 bluegill diet treatments, was higher in bluegill fed A. domesticus treatments than in treatments of bluegill fed D. pulex, suggesting differences in behavior based on the presence of different infochemicals. A conceptual model based on results from the present study and the broader literature suggests that infochemical landscapes may cause high association for Daphnia, planktivores, and piscivores with macrophytes, ultimately influencing food web structure through higher encounter rates among taxa.

Intensity of giraffe locomotor activity is shaped by solar and lunar zeitgebers

Natural cycles of light and darkness shift the balance of risks and gains for animals across space and time. Entrainment to photic cycles allows animals to spatiotemporally adapt their behavioural and physiological processes in line with interplaying ecological factors, such as temperature, foraging efficiency and predation risk. Until recently, our understanding of these chronobiological processes was limited by the difficulties of 24 h observations. Technological advances in GPS biotelemetry however are now allowing us unprecedented access to long-term, fine-scale activity data. Here we use data derived from frontline technology to present the first large-scale investigation into the effects of natural fluctuations of light and darkness on the locomotor activity patterns of a threatened African mega-herbivore, the giraffe (Giraffa spp.). Using data from a remote population of Angolan giraffe (G. g. angolensis) in the northern Namib Desert, Namibia, we reveal the first full picture of giraffe chronobiology in a landscape of fear. Furthermore, we present clear evidence of the effect of moonlight on the nocturnal activity patterns of large ungulates. Our results are in line with recent research demonstrating that, rather than a fixed internal representation of time (circadian clock), many surface-dwelling ungulates have plastic activity patterns that are vulnerable to modification by external factors including light and temperature. Relatedly, we highlight important conservation management implications of rising temperatures and increasing light pollution on the chronobiology of surface-dwelling mammals.

Terrestrial threats dominate the waterbird landscape of fear in a savannah pan wetland system

Natural or anthropogenic disturbances (stimuli that trigger a behavioural response from animals) can have direct consequences on fitness and population trends. This study aimed at investigating the relative influence of three types of disturbances (mammalian herbivores, terrestrial threats from ground predators and aerial threats) on the responses by waterbirds at waterpans in Hwange National Park (HNP, Zimbabwe) and adjacent land uses. Thirteen waterpans were monitored during daylight hours between years 2015 and 2017 and responses of waterbirds to the three forms of disturbances were recorded. Logistic regressions revealed that the likelihood of responding was highest after terrestrial threats; with individuals/groups that were initially engaged in non-feeding activities that allowed vigilance, responding the most. Wildfowl species spent significantly longer time flying (compared to waders and generalists), more so in communal areas (CAs) than HNP, and after terrestrial threats compared to aerial threats and herbivore disturbances. We did not find any differences in probability of responding across land uses probably because there is less human disturbance in HNP, but predation risk is high. Further, even though there are less terrestrial predators in CAs, domestic dogs may be maintaining the stimuli. We conclude that terrestrial threats are least tolerated, with species most susceptible to human predation (i.e. wildfowl) losing more time avoiding them. Interestingly, only acute aerial threats induced departure from waterpans. Our findings have a direct implication for waterbird conservation as herbivore and human density in this area are currently increasing.

Predation of a Brazilian porcupine (Coendou prehensilis) by an ocelot (Leopardus pardalis) at a mineral lick in the Peruvian Amazon

Many herbivorous and frugivorous Amazonian species, including several arboreal animals, feed on earth and water at mineral licks in the Amazon region to supplement their diet with micronutrients and clays. These species are vulnerable to predation during this activity. We recorded an adult Brazilian porcupine (Coendou prehensilis) being predated by an adult male ocelot (Leopardus pardalis) while drinking water at a mineral lick in the Maijuna-Kichwa Regional Conservation Area (MKRCA) in northeastern Loreto, Peru. This observation provides direct evidence arboreal species like the porcupine, which move slowly on the ground, are particularly vulnerable to terrestrial predators while visiting mineral licks. Mineral licks are important in the diets and ecology of Amazonian mammals, but arboreal prey must balance the trade-off between using the resource and being hunted. We suggest that mineral licks may be hotspots of risk in Amazonian prey species' landscape of fear.

Better safe than sorry: The response to a simulated predator and unfamiliar scent by the European hare

AbstractPredator presence can create a “landscape of fear,” which is defined as the spatially explicit distribution of perceived predation risk as seen by prey. Prey species can alter their behavior and space use as a response to increased predation risk, which might be traded off with energetic requirements. Thus, whether or not an anti‐predator behavior is performed might depend on the perceived risk. In this study, we investigated the behavioral and spatial response of the European hare (Lepus europaeus) toward the presence of a predator scent, using red fox (Vulpes vulpes) scat, an unfamiliar control scent (butyric acid), and a true control (no scent). We collected data on hare activity times and behavior using 50 camera trap locations and spatial data using GPS telemetry (30,481 GPS positions of 12 hares). Hares showed spatial anti‐predator behaviors within their home range, for example, the local avoidance of areas treated with scent and remaining further from field edges, in response to sympatric predator scent and partly also in response to unfamiliar butyric acid. Conversely, more costly anti‐predator behaviors, that is, increased vigilance at the expense of foraging, were only shown in response to the predator scent. Our results suggest that prey species respond flexibly toward scent cues, utilizing less costly anti‐predator behaviors independent of the perceived threat, whereas costly anti‐predator responses are only used in the presence of “real” threat. Further, our findings emphasize that a combination of camera trap and GPS data can provide detailed information on animal behavior and space use, and caution that interpretation of one data source alone might lead to incomplete conclusions.

On the landscape of fear: shelters affect foraging by dunnarts (Marsupialia, Sminthopsis spp.) in a sandridge desert environment

Abstract Disturbances such as fire reduce the structural complexity of terrestrial habitats, increasing the risk of predation for small prey species. The postfire effect of predation has especially deleterious effects in Australian habitats owing to the presence of invasive mammalian predators, the red fox (Vulpes vulpes) and feral cat (Felis catus), that rapidly exploit burned habitats. Here, we investigated whether the provision of artificial shelter could alleviate the risk of predation perceived by two species of small marsupial, the dunnarts Sminthopsis hirtipes and S. youngsoni, in open postfire habitat in the sandridge system of the Simpson Desert, central Australia. We installed artificial shelters constructed from wire mesh that allowed passage of the dunnarts but not of their predators at one site, and measured and compared the perceived risk of predation by the dunnarts there with those on a control site using optimal patch-use theory (giving-up densities, GUDs). GUDs were lower near artificial shelters than away from them, and near dune crests where dunnarts typically forage, suggesting that the shelters acted as corridors for dunnarts to move up to the crests from burrows in the swales. Foraging was lower near the crest in the control plot. Two-day foraging bouts were observed in dunnart activity, with recruitment to GUD stations occurring a day earlier in the augmented shelter plot. Despite these results, the effects of the shelters were localized and not evident at the landscape scale, with GUDs reduced also in proximity to sparse natural cover in the form of regenerating spinifex grass hummocks. Mapping dunnart habitat use using the landscape of fear (LOF) framework confirmed that animals perceived safety near shelter and risk away from it. We concluded that the LOF framework can usefully assess real-time behavioral responses of animals to management interventions in situations where demographic responses take longer to occur.

Cheetah communication at scent-marking sites can be inhibited or delayed by predators

Scent-marking is a way for individuals to indirectly communicate; however, the information is not exclusive to a single species and can be informative to a whole community. Prey or competitively inferior species can use scent-marks from predators/dominant species to avoid interactions. Cheetahs are a subordinate member of the large carnivore guild in Africa, yet olfactory communication in this guild has yet to be explored. We explore whether intraguild or intraspecific communication is occurring at cheetah scent-marking sites as well as whether dominant predator avoidance by cheetah occurs in response to predator presence or predator scent-marking. We recorded cheetah behaviour with video recording camera traps at cheetah scent-marking sites where a ‘landscape of fear’ was provided through natural predator presence or manipulated cues of predator presence. We found that cheetah took longer to return to scent-marking sites when a lion or a leopard was the previous species to visit the site. Moreover, cheetah increased the amount of time that they spent sniffing at scent-marking sites when another predator, as opposed to a cheetah, was the previous visitor. Finally, we noted that females never visited a scent-marking site after a predator was present nor when a predators’ scent-mark was present. Our results demonstrate that cheetahs use scent-marking sites for intraspecific communication, but also obtain intraguild information at these sites. Dominant predators can inhibit or at least delay important intraspecific communication around estrous events that occurs between cheetah at scent-marking sites, a novel form of interference competition. Competition occurs between species, and dominant species deprive subordinate species from key resources. Individuals are able to avoid the cost of direct interactions with competitors by using cues (both direct and indirect) such as scents to assess such risks. Using video recording cameras at cheetah scent-marking sites, we provide novel insight into how dominant predator species shape cheetah behaviour through the use of avoidance by cheetah to the presence of dominant predators. Scent-marking sites are important to cheetah communication around reproduction opportunities and territory maintenance; however, dominant predator species’ cues blocked female reproductive signalling at the sites and delay male visitation. This serves as a novel form of interference competition for cheetah, but we suggest that cheetahs maintain communication through the use of multiple sites.

Is landscape of fear of macroinvertebrate communities a major determinant of mesopredator and prey activity?

Macroinvertebrate foragers play an important role on the trophic structures of freshwater environments, and multiple trophic levels occur among macroinvertebrate communities providing very interesting scenarios for testing scientific hypotheses. One of the most intriguing aspect to understand is the role played by the landscape of fear (LOF) on macrobenthos density and activity. With this pilot study we wanted to test if LOF at the macrobenthos community levels plays a role in determining the density of both prey and mesopredators. During two consecutive years, we evaluated, with both day and night surveys, the density of two mesopredator triclad species and of one detritivore prey crustacean species, and we compared them to the number of respective predators occurring in the macroinvertebrate community. LOF levels at the macroinvertebrate community did not reduce the abundance of the target taxa. One of the triclad species was instead positively related to the levels of LOF assessed for it on the basis of the available knowledge. The broad implication of the research is that the abundance of freshwater macroinvertebrates is not mainly linked to the predation risk at the community level, suggesting that also for researches on macrobenthos LOF analyses should take in consideration the role of top predators.

We need to worry about Bella and Charlie: the impacts of pet cats on Australian wildlife

Research and management attention on the impacts of the introduced domestic cat (Felis catus) on Australian fauna have focussed mainly on the feral population. Here, we summarise the evidence for impacts of predation by pet cats on Australian wildlife. We collate examples of local wildlife population decline and extirpation as a result, at least in part, of predation by pet cats. We assemble information across 66 studies of predation by pet cats worldwide (including 24 Australian studies) to estimate the predation toll of pet cats in Australia, plus the predation pressure per unit area in residential areas. We compared these estimates to those published for feral cats in Australia. The per capita kill rate of pet cats is 25% that of feral cats. However, pet cats live at much higher densities, so the predation rate of pets per square kilometre in residential areas is 28–52 times larger than predation rates by feral cats in natural environments, and 1.3–2.3 times greater than predation rates per km2 by feral cats living in urban areas. Pet cats kill introduced species more often than do feral cats living in natural environments, but, nonetheless, the toll of native animals killed per square kilometre by pet cats in residential areas is still much higher than the toll per square kilometre by feral cats. There is no evidence that pet cats exert significant control of introduced species. The high predation toll of pet cats in residential areas, the documented examples of declines and extirpations in populations of native species caused by pet cats, and potential pathways for other, indirect effects (e.g. from disease, landscapes of fear, ecological footprints), and the context of extraordinary impacts from feral cats on Australian fauna, together support a default position that pet cat impacts are serious and should be reduced. From a technical perspective, the pet cat impacts can be reduced more effectively and humanely than those of feral cats, while also enhancing pet cat welfare. We review the management options for reducing predation by pet cats, and discuss the opportunities and challenges for improved pet cat management and welfare.

The Intersection of Human Disturbance and Diel Activity, with Potential Consequences on Trophic Interactions.

Direct effects of human disturbance on animal populations are well documented across habitats, biomes, and species, but indirect effects of diel have received less attention. An emerging field in applied ecology involves behavioral avoidance of or attraction to humans and their trappings. We posit trophic consequences, in terms of relative risk, for four species of mammals, each of which strongly avoids human activity, in urban reserves of coastal southern California. Two species, one predator and one prey, avoid human activity via a temporal shift to become "more nocturnal"-the species' activity is centered near dawn on days without human activity but nearer to midnight on days with human activity. Diel shifts have brought the species into greater overlap, respectively, with a key prey and a key predator, overlap that may increase encounter rate and thus increase relative risk of predation, with potential consequences for trophic dynamics and cascades: increased risk of predation may depress prey population, either directly (e.g., mortality) or indirectly (e.g., "landscape of fear"). Human use of reserves, especially in high population density regions, needs to be reconsidered either to reduce access or to restrict access entirely to areas that may provide refuge to both predators and prey.

Index to Titles and Authors/Editors of Books Reviewed

Index to Titles and Authors/Editors of Books Reviewed

Are all patterns created equal? Cooperation is more likely in spatially simple habitats

AbstractCooperative behaviours, such as aggregation with neighbouring conspecifics, can enhance resilience in habitats where risks (i.e. predation, physical disturbances) are high, exerting positive feedback loops to maintain a healthy population. At the same time, cooperation behaviours can involve some extra energy expenditures and increasing resource competition. For sessile reefs, like mussels, simulation models predict increased cooperation under increasing levels of environmental stress. Predation risk is viewed as a behaviour‐modifying stressor, but its role on cooperation mechanisms, such as likelihood of reciprocity, has not yet been empirically tested. This study harnesses this framework to understand how cooperation changes under different perceived levels of predation risk, using mussel beds as model of a complex “self‐organised” system. Hence, we assessed the context dependency of cooperation response in different “landscapes of fear,” created by changes in predator cues, substratum availability and body size. Our experiments demonstrated that i) cooperation in a mussel bed system increases when predator cues are present, but that this relationship was found to be both, ii) strongly context‐dependent, particularly upon substratum availability and iii) size‐dependent. That is, while cooperation is in general greater for larger individuals, the response to risk results in greater cooperation when alternative attachment substratum is absent, meaning that simpler landscapes may be perceived as riskier. The context dependency of structural complexity is also an essential finding to consider in a changing world where habitats are losing complexity and cooperative strategies should be maximised.

Black bears alter movements in response to anthropogenic features with time of day and season

BackgroundWith the growth and expansion of human development, large mammals will increasingly encounter humans, elevating the likelihood of human-wildlife conflicts. Understanding the behavior and movement of large mammals, particularly around human development, is important for crafting effective conservation and management plans for these species.MethodsWe used GPS collar data from American black bears (Ursus americanus) to determine how seasonal food resources and human development affected bear movement patterns and resource use across the Commonwealth of Massachusetts.ResultsWe found that though bears moved more and avoided human development during crepuscular and daylight hours than at night, bears preferentially moved through human dominated areas at night. This indicates bears were mitigating the risk of human development by altering their behavior to exploit these areas when human activity is low. This behavioral shift was most prominent in the spring, when natural foods are scarce, and fall, when energetic demands are high. We also observed a high degree of inter-individual variability among our sample of bears. Bears with a higher density of houses in their home ranges (~ 75 houses/km2) displayed less avoidance of human development than more rural bears. Furthermore, bear movement models had different explanatory variables, with preference or avoidance of a variable being dependent on the individual bear. To account for this individuality in our predictive surfaces, we projected the probability of movement for each season and time of day using a spatially weighted surface centered on each bear’s home range.ConclusionsWe found that black bears in Massachusetts are operating in a landscape of fear and are altering their movement patterns to use developed areas when human activity is low. We also found seasonal and diel differences among individual bears in resource selection during movement. Accounting for these individual, seasonal, and diel differences when assessing movement for large mammals is especially important if predictive surfaces are to be used in identifying areas for conservation and management.

Bearding the scorpion in his den: desert isopods take risks to validate their ‘landscape of fear’ assessment

Animals balance the risk of predation against other vital needs by adjusting their spatial behavior to match spatiotemporal variation in predation risk. To map this ‘landscape of fear’, prey use evolutionary rules of thumbs that are associated with the activity and hunting efficiency of predators. In addition, prey acquire perceptual information about the presence, identity and state of potential predators and use these cues to focus their acute anti‐predatory responses. Our goal was to explore if and how prey also use such perceptual information that decays with time to update their spatiotemporal risk assessment. We placed scorpions in freshly dug burrows and recorded the spatial activity and defense behavior of their isopod prey upon encountering the burrows straight after settling the scorpions and seven days later. To corroborate our understanding, we also examined the isopods’ detailed reactions towards deserted scorpion burrows. The isopods reacted defensively to scorpion burrows during their first encounter. After seven days, proportionally more isopods approached the scorpion burrows on their way out for foraging and fewer isopods encountered it on their way back. No changes in the spatial activity were observed towards deserted burrows. In addition, on the eighth day, more isopods entered the risky area near the scorpion burrows when leaving their own burrow than on the first encounter. The results suggest that isopods used predator cues to readjust the ‘landscape of fear’. Yet, rather than avoiding the dangerous areas altogether, the isopods implemented risky inspection behavior, validating whether the danger is actual. Our findings imply that inspection behavior toward predators can be used for future planning of prey spatial activity, offsetting possible ‘information decay costs’.

Wand plant architecture in the Fynbos: Testing the rodent herbivory hypothesis

Throughout the Cape Floristic Region, in a range of local environments, can be found a distinctive growth form: “wand” plants. This curious plant architecture comprises perennial plants which have slender (wand-like) stems that extend high above the matrix vegetation. We explore whether the evolution of wand-plants may have been driven by plant–herbivore interactions with rodents, where such architecture reduces access to nutrient rich flowers and seeds. To test this idea, we determined if (i) wand-plants were more flexible than non-wand congeners, and (ii) a stabilised wand plant was favoured for climbing (by laboratory mice) over a free-standing wand plant in a laboratory setting. Under a phylogenetic independent contrast framework, wand-plants were not more flexible (across a range of diameters) than non-wand congeners. Also, laboratory mice showed no differences in preference for, or success on, free-standing and stabilised wand-plants. We discuss a range of alternative ideas, including that the architecture may be a coevolutionary relic, to increase pollination visitation, to increase leaf-level water-use efficiency or to maintain cooler leaf temperatures in warm and/or windless environments. However, we suggest that our study may be flawed as it did not include the “landscape of fear” — i.e. the predation risk associated with exposure along a bare stem — and that rodent herbivory may nonetheless be the dominant evolutionary driver. Although we do not find any support for the hypothesis of an arms race between wand plants and rodent herbivores, this fascinating architecture remains unexplained and we hope that our study will stimulate further exploration of the topic.

Nest predator avoidance during habitat selection of a songbird varies with mast peaks and troughs

Predation risk is vital in determining habitat quality. But landscapes of fear are complex and dynamic, such as temperate deciduous forests characterized by intermittent, synchronized production of large seed crops (mast peaks). These “resource pulses” elevate the magnitude of predation risk via direct or indirect effects, possibly altering also predator avoidance strategies of a prey. Yet, how animals manage predation risk via informed habitat selection and how this depends on ecological context remains poorly explored. We studied risk-sensitive settlement behavior of wood warbler Phylloscopus sibilatrix. We tested the hypothesis that warblers flexibly avoid predators (Eurasian jays Garrulus glandarius) during habitat selection but that their interactions are mediated by mast seeding, which is known to elevate the overall nest predation risk for warblers through its cascading effects on population dynamics of rodents and generalist predators. We used a playback experiment to manipulate warblers’ perceived risk of nest predation by jays. We replicated the experiment in two consecutive years, followed by high or low seed crop. In the spring following mast trough, risky jay plots featured low abundance, late settlement, and poor pairing success compared to other treatments. In contrast, no response differences were found in the spring following mast seeding. Our results suggest that the way wood warblers adjust habitat choices to jay predation risk is indirectly mediated by mast seeding. This highlights plasticity in predator avoidance during prey habitat selection in complex and dynamic landscapes of fear, and the potential effects of mast seeding on animal behavior via indirect interactions.Significance statementAvoiding places with high nest predation risk during settlement decisions is believed to be widespread in birds. However, the mechanistic understanding of how birds acquire and use information about ambient nest predation risk to fine-tune settlement decisions is still limited. Using a playback experiment, we show that wood warblers eavesdrop on predator calls and avoid settling at sites with high perceived risk of nest predation by Eurasian jays. However, the way warblers adjust habitat choices to the nest predation risk posed by jays appears to be affected by tree mast seeding. This is potentially due to cascading effects of masting on the population dynamics of rodents and generalist predators, creating temporal peaks of elevated nest predation risk for wood warblers. Our study highlights plasticity in predator avoidance during prey settlement behavior in temporally variable, pulsed-resources ecosystems.

Landscape of fear and human-predator coexistence: Applying spatial predator-prey interaction theory to understand and reduce carnivore-livestock conflict

In recent decades the ‘landscape of fear’ has grown in popularity to become a central consideration in wildlife management, and has even been reconceptualized as the ‘landscape of coexistence’ for understanding human-wildlife conflicts such as predator attacks on livestock. Yet fear effects are not always the predominant driver of predator-prey interactions. Thus, guiding ecological principles have not been assembled to explain the broader food web interactions that shape the context dependency of carnivore-livestock conflict. We address this gap by developing a conceptual framework as a way to think about the contingencies under which inducing non-consumptive ‘fear effects’ on predators would be effective to mitigate carnivore-livestock conflict. The framework specifically considers interactions among wildlife (carnivore predators, wild ungulate prey) and humans (people and livestock) in terms of spatial predator-prey assemblages in which the nature of wildlife-human interactions – as either a carnivore-livestock conflict or a coexistence food web – is contingent on the nature of spatial movement and overlap of humans and wildlife across landscapes. Considering human-wildlife interactions within such a spatial food web context can assist in enabling people and wildlife, especially imperiled carnivores, to coexist in human-modified landscapes. The framework offers predictions that should be tested via adaptive management experiments that evaluate whether conflict mitigation solutions aligned with particular spatial human-livestock-carnivore contexts do indeed resolve conflict.