Prey Characteristics Research Articles

Variable juvenile growth rates and offspring size: a response to anthropogenic shifts in prey size among populations.

Environmental variables, such as resource quality, shape growth in organisms, dictating body size, an important correlate of fitness. Variation in prey characteristics among populations is frequently associated with similar variation in predator body sizes. Anthropogenic alterations to prey landscapes impose novel ecological pressures on predators that may shift predator phenotypes. Research has focused on determining the adaptability of the phenotypic response by testing its genetic heritability. Here, we asked if anthropogenic shifts in prey size across the landscape correlate with juvenile growth rates among populations of watersnakes with divergent life-history phenotypes. We sought to determine if growth rate variation is the product of genetic adaptation or a non-heritable phenotypic response. Using a common-garden design, we measured growth of neonate snakes from fish farms varying in prey size. We found juvenile growth rates are faster for snakes with larger initial body sizes and from populations with larger average prey sizes. Our data suggest variability in juvenile grow rates within and among populations are not the product of genetic adaptation, but the indirect consequence of initial offspring size variation and prey consumption. We propose larger offspring sizes may favor increased juvenile growth rates, mediated through a larger morphological capacity to consume and process energy resources relative to smaller individuals. This experiment provides evidence supporting the growing body of literature that non-heritable responses may be significant drivers of rapid phenotypic divergence among populations across a landscape. This mechanism may explain the stability and colonization of populations in response to rapid, human-mediated, landscape changes.

Does size matter? Exploring the influence of body size on predator–prey relationships, hunting mode and prey characteristics in Neotropical fishes

Does size matter? Exploring the influence of body size on predator–prey relationships, hunting mode and prey characteristics in Neotropical fishes

Characterizing prey fields in humpback whale foraging areas of southern British Columbia

Humpback whales ( Megaptera novaeangliae) use southern British Columbia waters to feed, but the type and quantity of prey in many areas used for feeding is unknown. We conducted active acoustic prey mapping in 55 small grid-surveys in two regions off Vancouver Island. We quantitatively compared fish and zooplankton-dominated biomass in known feeding areas with and without foraging humpback whales, and qualitatively described the prey characteristics of the foraged areas. Surveys of the water column suggest that, on average, humpback whale foraging was associated more with increased zooplankton than fish biomass. Prey characteristics varied between the two regions (∼500 km apart), but there was no significant difference in mean backscatter strength in the actively foraged areas between the two regions. Frequency differencing discriminated between the dominant taxa in the water column, but potential epipelagic prey (<10 m) would have been omitted from analysis. However, average depth at the maximum acoustic prey detections was significantly deeper when whales were present (84 m) versus absent (60 m), suggesting predominantly subsurface foraging opportunities suitable to prey mapping.

Proactive cursorial and ambush predation risk avoidance in four African herbivore species.

Most herbivores must balance demands to meet nutritional requirements, maintain stable thermoregulation and avoid predation. Species-specific predator and prey characteristics determine the ability of prey to avoid predation and the ability of predators to maximize hunting success. Using GPS collar data from African wild dogs, lions, impala, tsessebes, wildebeest and zebra in the Okavango Delta, Botswana, we studied proactive predation risk avoidance by herbivores. We considered predator activity level in relation to prey movement, predator and prey habitat selection, and preferential use of areas by prey. We compared herbivore behaviour to lion and wild dog activity patterns and determined the effect of seasonal resource availability and prey body mass on anti-predator behaviour. Herbivore movement patterns were more strongly correlated with lion than wild dog activity. Habitat selection by predators was not activity level dependent and, while prey and predators differed to some extent in their habitat selection, there were also overlaps, probably caused by predators seeking habitats with high prey abundance. Areas favoured by lions were used by herbivores more when lions were less active, whereas wild dog activity level was not correlated with prey use. Prey body mass was not a strong predictor of the strength of proactive predation avoidance behaviour. Herbivores showed stronger anti-predator behaviours during the rainy season when resources were abundant. Reducing movement when top predators are most active and avoiding areas with a high likelihood of predator use during the same periods appear to be common strategies to minimize predation risk. Such valuable insights into predator-prey dynamics are only possible when using similar data from multiple sympatric species of predator and prey, an approach that should become more prevalent given the ongoing integration of technological methods into ecological studies.

Evaluating the Use of Chemical Weapons for Capturing Prey by a Venomous Mammal, the Greater Slow Loris (Nycticebus coucang).

Few mammals are venomous, including one group of primates-slow (Nycticebus spp.) and pygmy (Xanthonycticebus spp.) lorises. Hypotheses for the evolutionary function of venom in these primates include defense from predators or ectoparasites, communication or competition with conspecifics, and the capture of prey. We tested the prey capture hypothesis in 75 trials with 22 wild-caught greater slow lorises (N. coucang) housed in a rescue center in Java, Indonesia. We experimentally offered the slow lorises arthropod prey items varying in size, escape potential, and toxicity and recorded venom-related and predatory behaviors using live and video observations. The slow lorises visually targeted arthropod prey, approached it quickly and efficiently, and captured it with a manual grasping motion. They rarely performed venom-related behaviors and seemed to do so in a defensive context. The slow lorises exhibited little variation in pre-capture behavior as a function of prey size or escape potential. In response to noxious prey, the slow lorises performed tongue-flicking and other investigative behaviors that indicate they are using chemosensory input to assess prey characteristics. These data suggest it is unlikely that slow lorises use chemical weapons to subdue arthropod prey and may support, instead, a defensive function for slow loris venom.

Interaction of sound-audition traits between eared insects and arthropodophagous bats: using a DNA approach to assess diet

Abstract Arthropod–bat interactions are often considered as a base model for studying factors underlying predator–prey coevolutionary processes. Bats developed ultrasonic echolocation to hunt, and in response some arthropods developed defense mechanisms such as ultrasonic hearing, allowing them to elude bat predators. The present study analyzes the feeding patterns of bats, focusing on sonic-auditory sensory mechanisms in predator–prey interactions. Next-generation DNA sequence data from fecal samples were used to analyze the diet of 17 bat species from Mexico. Arthropod prey taxa were classified according to their auditory traits, and echolocation data were recompiled from literature review. We: (i) classified arthropod families according to their hearing ability; (ii) estimated arthropod taxon richness and proportion in the diet of each bat species; and (iii) used multidimensional scaling, principal component analysis, and regression to analyze prey consumption patterns in relation to their auditory traits and in relation to echolocation characteristics of bats. Finally, we analyzed the relationship between foraging time and auditory characteristics of prey. Families with hearing organs correspond to the orders Lepidoptera and Orthoptera. We registered 20 families of Lepidoptera and 5 of Orthoptera—7 and 3 with hearing organs, respectively. Of these orders, families lacking ears were recorded in the diet of a few bat species. Our results support the allotonic frequency hypothesis predicting a difference in emission frequency intervals between predator and prey. However, we found that the consumption of earless moths is less frequent and is related to diurnal and twilight activity—hence, their consumption is limited to bat species foraging early. Results indicate bats feed on arthropod prey successfully despite the ultrasonic hearing ability of the prey. These results may be due to counteradaptations that allow maintenance of an asymmetric “arms race” between bats and eared insects that favors the predator.

Bioenergetic modelling of a marine top predator's responses to changes in prey structure.

Determining how animals allocate energy, and how external factors influence this allocation, is crucial to understand species' life history requirements and response to disturbance. This response is driven in part by individuals' energy balance, prey characteristics, foraging behaviour and energy required for essential functions. We developed a bioenergetic model to estimate minimum foraging success rate (FSR), that is, the lowest possible prey capture rate for individuals to obtain the minimum energy intake needed to meet daily metabolic requirements, for female sperm whale (Physeter macrocephalus). The model was based on whales' theoretical energetic requirements using foraging and prey characteristics from animal-borne tags and stomach contents, respectively. We used this model to simulate two prey structure change scenarios: (1) decrease in mean prey size, thus lower prey energy content and (2) decrease in prey size variability, reducing the variability in prey energy content. We estimate the whales need minimum of ~14% FSR to meet their energetic requirements, and energy intake is more sensitive to energy content changes than a decrease in energy variability. To estimate vulnerability to prey structure changes, we evaluated the compensation level required to meet bioenergetic demands. Considering a minimum 14% FSR, whales would need to increase energy intake by 21% (5-35%) and 49% (27-67%) to compensate for a 15% and 30% decrease in energy content, respectively. For a 30% and 50% decrease in energy variability, whales would need to increase energy intake by 13% (0-23%) and 24% (10-35%) to meet energetic demands, respectively. Our model demonstrates how foraging and prey characteristics can be used to estimate impact of changing prey structure in top predator energetics, which can help inform bottom-up effects on marine ecosystems. We showed the importance of considering different FSR in bioenergetics models, as it can have decisive implications on estimates of energy acquired and affect the conclusions about top predator's vulnerability to possible environmental fluctuations.

Spies of the deep: An animal-borne active sonar and bioluminescence tag to characterise mesopelagic prey size and behaviour in distinct oceanographic domains

Mesopelagic fishes, a central component of marine trophic networks, play a fundamental role in marine ecosystems. However, as they live in highly inaccessible environments, little information is currently available on their distribution and abundance. The emergence of biologging technologies has made it possible to use deep-diving predators as bio-samplers of their environment in under-sampled regions. In this work, we deployed an innovative miniaturised sonar tag that combines active acoustics with high-resolution GPS, pressure, movement and light sensors on Southern elephant seals, a deep-diving predator feeding on mesopelagic prey. Seals were also equipped with Conductivity-Temperature-Depth tags. Salinity and temperature depth profiles were used to define oceanographic domains, allowing us to explore distribution and ecology of mesopelagic prey targeted by seals and the seals’ foraging behaviour. We highlighted strong vertical differences in prey characteristics and behaviour, with larger, more evasive and less bioluminescent prey in deeper waters. Moreover, prey encountered in warmer waters were found deeper, were more evasive and displayed a more marked diel vertical migration behaviour compared to prey encountered in colder waters, suggesting that prey accessibility and characteristics differ according to oceanographic domains. This study highlights the usefulness of the sonar-bioluminescence tag to infer mesopelagic prey distribution and habitat when deployed on deep-diving predators such as elephant seals.

Qualitative analysis of a prey–predator model with prey refuge and intraspecific competition among predators

In this study, we consider a prey–predator model with prey refuge and intraspecific competition between predators using the Crowley–Martin functional response and investigate the dynamic characteristics of spatial and nonspatial prey–predator systems via both analytical and numerical methods. The local stability of nontrivial interior equilibrium, the existence of a Hopf bifurcation, and the stability of bifurcating periodic solutions are obtained in the absence of diffusion. For the spatial system, the Turing and non-Turing patterns are evaluated for some set of parametric belief functions, and we obtain some interesting results in terms of prey and predator inhabitants. We present the results of numerical simulations that demonstrate that both prey and predator populations do not converge to a stationary equilibrium state at any foreseeable future time when the parametric values are processed in the Turing domain.

Temperate bats may alter calls to partially compensate for weather-induced changes in detection distance.

Echolocation is the use of self-emitted calls to probe the surrounding environment. The atmosphere strongly absorbs sound energy, particularly high frequencies, thereby limiting the sensory range of echolocating animals. Atmospheric attenuation varies with temperature and humidity, which both vary widely in the temperate zone. Since echolocating insectivorous bats rely on ultrasound to capture insects, their foraging success might decrease with seasonal and daily variations in weather. To counteract weather-induced variations in prey detection, we hypothesised that European bats decrease call frequency and increase call energy when atmospheric attenuation increases, thereby maintaining their prey detection distance. Using acoustic localisation and automated call analysis, we measured call frequency and energy in free-flying bats of three common European insectivorous species. One species, Pipistrellus nathusii/kuhlii, increased call frequency, but simultaneously decreased call energy, while the two other species (P. pipistrellus and Myotis daubentonii) did not alter call parameters. We estimated the detection distance for prey based on the recorded call parameters and prey characteristics, using a custom-developed theoretical model. None of the three species maintained prey detection distance (it decreased by 1.7 to 3.4 m) when atmospheric attenuation increased. This study contributes to a better understanding of the sensory challenges faced by animals in fluctuating environments.

Cover Image

EcosphereVolume 14, Issue 3 e4119 COVER IMAGEOpen Access Cover Image First published: 06 March 2023 https://doi.org/10.1002/ecs2.4119AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Graphical Abstract COVER PHOTO: Adélie penguins (Pygoscelis adeliae) have life histories dependent on suitable sea ice, landscape, seascape, and preyscape conditions—making them a valuable indicator of climate change and variability. Long-term patterns in ecosystem phenology were investigated from the perspective of Adélie penguins using data from the Palmer Antarctica Long Term Ecological Research (LTER) program. Cimino et al. (Ecosphere, Volume 14, Issue 2, Article e4417; doi: 10.1002/ecs2.4417) show that sea ice retreat and increasing photoperiod in the spring trigger a sequence of events from late spring into summer, including Adélie penguin clutch initiation, snow melt, calm weather, phytoplankton blooms, particulate organic carbon flux, peak whale abundances, and bacterial accumulation. Later sea ice retreat generally resulted in events happening later and the ecosystem was more “predictable” than early retreat years. The timing of the Adélie penguins breeding cycle was relatively consistent compared to other events, making them susceptible to mismatches in optimal environmental windows or prey characteristics that could ultimately influence chick survival. Photo credit: Darren Roberts Volume14, Issue3March 2023e4119 RelatedInformation

A Review of Factors Affecting the Susceptibility of Juvenile Salmonids to Avian Predation

AbstractWe reviewed studies of piscivorous colonial waterbird predation on juvenile salmonids to synthesize current knowledge of factors affecting fish susceptibility to avian predators. Specifically, we examined peer‐reviewed publications and reports from academic, governmental, and nongovernmental agencies to identify commonalities and differences in susceptibility of salmonids to avian predation, with a focus on mark–recovery studies in the Columbia River basin. Factors hypothesized to influence salmonid susceptibility to avian predation were grouped into four general categories: (1) salmonid species and populations, (2) environmental factors, (3) prey density, predator density, and migration timing, and (4) prey characteristics. Our review focused on predation by Caspian terns Hydroprogne caspia, double‐crested cormorants Nannopterum auritum, and gull species Larus spp. as these are the most well‐studied avian predators of salmonids. Results indicated that predator–prey interactions varied across salmonid species and populations and species of avian predator. Inferences across studies supported multiple hypotheses regarding predator–prey dynamics, including environmental factors that influence prey exposure to predators (e.g., river flows, turbidity, alternative prey), variation in predator and prey abundances, predator characteristics (e.g., foraging behavior, colony location), and prey characteristics (e.g., fish length, condition). Mark–recovery studies of avian predation on fish populations have greatly improved our understanding of the factors affecting fish susceptibility to avian predation, the relative contributions of abiotic and biotic factors to predation susceptibility, and the extent to which avian predation affects fish survival and the viability of prey populations. Future studies that jointly model predation and survival and the factors affecting those processes will further broaden our understanding of predator–prey dynamics and directly evaluate the effects of predation on prey population dynamics.

Long‐term patterns in ecosystem phenology near Palmer Station, Antarctica, from the perspective of the Adélie penguin

AbstractClimate change is leading to phenological shifts across a wide range of species globally. Polar oceans are hotspots of rapid climate change where sea ice dynamics structure ecosystems and organismal life cycles are attuned to ice seasonality. To anticipate climate change impacts on populations and ecosystem services, it is critical to understand ecosystem phenology to determine species activity patterns, optimal environmental windows for processes like reproduction, and the ramifications of ecological mismatches. Since 1991, the Palmer Antarctica Long‐Term Ecological Research (LTER) program has monitored seasonal dynamics near Palmer Station. Here, we review the species that occupy this region as year‐round residents, seasonal breeders, or periodic visitors. We show that sea ice retreat and increasing photoperiod in the spring trigger a sequence of events from mid‐November to mid‐February, including Adélie penguin clutch initiation, snow melt, calm conditions (low winds and warm air/sea temperature), phytoplankton blooms, shallow mixed layer depths, particulate organic carbon flux, peak humpback whale abundances, nutrient drawdown, and bacterial accumulation. Subsequently, from May to June, snow accumulates, zooplankton indicator species appear, and sea ice advances. The standard deviation in the timing of most events ranged from ~20 to 45 days, which was striking compared with Adélie penguin clutch initiation that varied <1 week. In general, during late sea ice retreat years, events happened later (~5 to >30 days) than mean dates and the variability in timing was low (<20%) compared with early ice retreat years. Statistical models showed the timing of some events were informative predictors (but not sole drivers) of other events. From an Adélie penguin perspective, earlier sea ice retreat and shifts in the timing of suitable conditions or prey characteristics could lead to mismatches, or asynchronies, that ultimately influence chick survival via their mass at fledging. However, more work is needed to understand how phenological shifts affect chick thermoregulatory costs and the abundance, availability, and energy content of key prey species, which support chick growth and survival. While we did not detect many long‐term phenological trends, we expect that when sea ice trends become significant within our LTER time series, phenological trends and negative effects from ecological mismatches will follow.

Does prey characteristics influence web-building plasticity of the ecologically dominant orb-web weaving spider, Neoscona theisi (Walckenaer 1841)?

Does prey characteristics influence web-building plasticity of the ecologically dominant orb-web weaving spider, Neoscona theisi (Walckenaer 1841)?

Visual prey categorization by a generalist jumping spider

The majority of jumping spiders are visual hunters that capture a wide range of prey. While they are known to use specific predatory techniques against different prey, their prey identification mechanisms are poorly understood. A generalist jumping spider, Yllenus arenarius, employs different predatory techniques to capture prey with two different escape potentials. The aim of the present study was to identify the characteristics used by the spider to classify prey into one of these categories. Freshly-emerged spiderlings were used in the experiments to analyse pre-programmed visual predatory preferences. The spiders were presented with: a) their natural prey with different escape potentials (flies, thrips, caterpillars) and b) video images constructed from different combinations of features of their natural prey. The images varied with regard to five characteristics: body length (short vs long images), the presence or absence of details (0 or 4 details, including head spot, antennae, legs, wings), the local motion of legs (moving vs still), the type of global motion (crawling vs non-crawling) and the direction of global motion (horizontal motion vs vertical small scale jumps). Prey-specific behaviours indicated which characteristics were used by the spider to ascertain the prey’s escape potentials. Our findings indicate that during visual prey categorization, Y. arenarius can rely solely on general prey characteristics, such as body proportions and the type of prey motion, while ignoring other stimuli, such as the presence of details and the local motion of legs. This mechanism of prey identification, based on these two easily-recognizable prey characteristics, enables fairly quick and precise categorization of a wide range of prey according to their escape potentials. The study shows how generalist jumping spiders can categorize their diverse prey into a limited number of groups and discusses the presence of the mechanism in other jumping spiders and other animals.

Lack of anti-predator recognition in a marine isopod under the threat of an invasive predatory crab

The prey naïveté hypothesis suggests that the failure of prey to recognize novel predators as a threat is caused by a lack of anti-predator adaptations. We tested this hypothesis in a unique natural setting, where the isopod Idotea balthica encountered the rapidly spreading invasive crab, Rhithropanopeus harrissii. Earlier research had indicated high mortality of the isopods during exposure to R. harrissii. The isopod exerted no co-evolutionary history with any littoral crabs and thus the strong impact could be caused by lack of pre-adaptations towards the new predator species. We tested this hypothesis by studying the anti-predator responses of the isopods with water-born cues of R. harrissii and of the native predatory fish Perca fluviatilis. Compared to control water, the isopods lowered their activity when exposed to the fish cue. Instead crab cue did not induce anti-predator behaviour. We also tested the hypothesis that mortality caused by novel predator, similar to predation by P. fluviatilis, would result in differential selection for the two sexes and contribute to the evolution of personalities. However, we found no differences in anti-predator behaviour nor in mortality between the sexes or personalities of the isopods. The outcomes reveal an interesting evolutionary scenario, where predation by a local predator induce soft selection on prey characteristics, but an invasive species cause hard selection without differentiating between prey individuals. Our study—conducted in the dawn of the population outbreak of R. harrissii—provides an excellent reference point for studies resolving the evolutionary impacts of invasive predators on naïve prey.

Quantity over quality? Prey-field characteristics influence the foraging decisions of little penguins (Eudyptula minor).

Quantifying prey characteristics is important for understanding the foraging behaviour of predators, which ultimately influence the structure and function of entire ecosystems. However, information available on prey is often at magnitudes which cannot be used to infer the fine-scale behaviour of predators, especially so in marine environments where direct observation of predator–prey interactions is rarely possible. In the present study, animal-borne video data loggers were used to determine the influence of prey type and patch density on the foraging behaviour of the little penguin (Eudyptula minor), an important predator in southeastern Australia. We found that numerical density positively influenced time spent foraging at a patch. However, when accounting for calorific value in density estimates, individuals spent longer at dense patches of low-quality prey. This may reflect a trade-off between capture effort and calorific gain as lower quality prey were captured at higher rates. During the breeding season, foraging trip distance and duration is constrained by the need to return to the colony each day to feed offspring. The results of the study suggest that, under these spatio-temporal constraints, little penguins maximize foraging performance by concentrating efforts at larger quantities of prey, irrespective of their calorific quality.

Taxonomic versus ecological prey traits among arthropodophagous bats: implications for surveying trophic partitioning patterns

Abstract Species can coexist spatially and temporally by partitioning the niche space and forming complex assemblages made up of different species that share the prey resource. Chiroptera is the second most species-rich mammalian order and about 75% of bat species feed on arthropods, which makes these bats a good model group for studying complex trophic interactions. Next-generation parallel sequencing techniques allow a detailed analysis of arthropod resource partitioning patterns in bats. However, previous studies have not reached a consensus on the concordance between diet composition, habitat use, and segregation of trophic resources in bats. We analyzed diet composition in terms of taxonomy of the insect prey, and the prey characteristics. Feces of 16 bat species were examined in the Mexican Neotropics. We carried out a SIMPER (similarity percentage) test, nonmetric multidimensional scaling, and principal component analyses to identify general segregation patterns of trophic resources in relation to the habitat-use guild of bats and computed Pianka’s niche overlap index between species and Levin’s index to estimate the niche width of each species. Bats from the same locality tend to partition their diet, with a niche overlap ranging between 0.5 and 0.8. The highest values were found between species with different foraging behaviors. We suggest that future bat diet studies should incorporate the ecological and taxonomic information of arthropod prey to better understand the trophic interactions with bats.

Resilience of Nematode Connectomes Based on Network Dimension-reduced Method

The whole map of nematode connectomes provides important structural data for exploring the behavioral mechanism of nematodes, but to further reveal the functional importance and resilience pattern of nematode neurons, it is necessary to effectively couple the regulatory relationship between neurons and their topology. Here, with a typical signal excitation function we propose a model to capture the interacting relationship between the neurons, because a differential equation depicts the activity of a neuron, n neurons mean we need high-D differential equations to capture the neural network. With mean-field theory, we decouple this N-dimension question into a one-dimension problem mathematically. In our framework, we emphatically analyze the characteristics, similarities and differences of the structure and dynamical behaviors of the neuronal system for Caenorhabditis elegans and Pristionchus pacificus. The comparing results of simulating method and theoretical approach show that the most important homologous neurons between C.elegans and P.pacificus are I2 and NSM, which may lead to their different behavior characteristics of predation and prey. At the same time, we expect that the xeff index can be used to reveal the importance of neurons for the functional evolution and degeneration of neural networks from a dynamic perspective. In the hermaphroditic and male C.elegans, we test the control level of the intermediate neuron groups over the output neuron groups and the single neuron. These results suggest that our theoretical approach can be used to reveal the effects of bio-connectivity groups, potentially enabling us to explore the interaction relationship of neural networks in humans and animals.

Prey Foraging Behavior After Predator Introduction Is Driven by Resource Knowledge and Exploratory Tendency

Predator reintroductions are often used as a means of restoring the ecosystem services that these species can provide. The ecosystem consequences of predator reintroduction depend on how prey species respond. Yet, to date, we lack a general framework for predicting these responses. To address this knowledge gap, we modeled the impacts of predator reintroduction on foragers as a function of predator characteristics (habitat domain; i.e., area threatened) and prey characteristics (knowledge of alternative habitat and exploratory tendency). Foraging prey had the capacity to both remember and return to good habitat and to remember and avoid predators. In general, we found that forager search time increased and consumption decreased after predator introduction. However, predator habitat domain played a key role in determining how much prey habitat use changed following reintroduction, and the forager's knowledge of alternative habitats and exploratory inclinations affected what types of habitat shifts occurred. Namely, habitat shifts and consumption sacrifices by prey were extreme in some cases, particularly when they were pushed far from their starting locations by broad-domain predators, whereas informed foragers spent less time searching and displayed smaller reductions to consumption than their naïve counterparts following predator exposure. More exploratory foragers exhibited larger habitat shifts, thereby sacrificing consumption but reducing encounters by relocating to refugia, whereas less exploratory foragers managed risk in place and consequently suffered increased encounters while consuming more resources. By implication, reintroductions of predators with broad habitat domains are especially likely to impose foraging and movements costs on prey, but forager spatial memory state can mitigate these effects, as informed foragers can better access alternate habitat and avoid predators with smaller reductions in consumption.