A skewed literature: Few studies evaluate the contribution of predation‐risk effects to natural field patterns

Ecology Letters, Journal Year: 2022, Volume and Issue: 25(9), P. 2048 - 2061

Published: Aug. 4, 2022

A narrative in ecology is that prey modify traits to reduce predation risk, and the trait modification has costs large enough cause ensuing demographic, trophic ecosystem consequences, with implications for conservation, management agriculture. But a long history of emphasising quantifying importance an ecological process ultimately requires evidence linking unmanipulated field patterns. We suspected such process-linked-to-pattern (PLP) studies were poorly represented risk literature, which conflicts confidence often given effects. reviewed 29 years literature revealed there are well over 4000 articles on Of those, 349 examined effects fitness measures or abundance (i.e., non-consumptive effects) only 26 PLP studies, while 275 other interacting species trait-mediated indirect 35 studies. narrowly focused taxonomically included three patterns abundance. Before concluding widespread influential role predation-risk effects, more attention must be observed across diverse ecosystems.

Language: Английский

---

Population and community consequences of perceived risk from humans in wildlife

Ecology Letters, Journal Year: 2024, Volume and Issue: 27(6)

Published: June 1, 2024

Abstract Human activities catalyse risk avoidance behaviours in wildlife across taxa and systems. However, the broader ecological significance of human‐induced perception remains unclear, with a limited understanding how phenotypic responses scale up to affect population or community dynamics. We present framework informed by predator–prey ecology predict occurrence non‐consumptive effects (NCE) trait‐mediated indirect (TMIE) anthropogenic disturbances. report evidence from comprehensive review different types behavioural physiological changes their influence on vital rates parameters wildlife. Evidence for NCEs TMIEs is mixed, half published studies finding relationship between human activities, change outcomes. The net depend mismatch response lethality activity. strong research biases taxa, systems, disturbance demographic measures prevent unified inference about prevalence activities. Coexistence conservation requires additional linking

Language: Английский

---

Similar Conditions With Opposite Effects: Predation‐Risk Effects on Prey Abundance Are Highly Contingent

Ecology and Evolution, Journal Year: 2025, Volume and Issue: 15(1)

Published: Jan. 1, 2025

ABSTRACT Experiments have shown that predation‐risk effects on prey fitness can be highly contingent environmental conditions, suggesting a potential difficulty in generalizing risk abundance natural settings. Rather than study the influence of particular controlled factor, we examine problem with novel approach. We examined multiple experiments performed under similar conditions. Any differences would typically deemed incidental, is, they not given attention methodology, nor presented as factors affecting results or inferences. Therefore, any magnitude and direction among indicate population are strongly influenced by context communities. The were conducted objectives, measurables implementation, captured much complexity systems (e.g., diverse assemblages (≥ 11 taxa) over generations). Our highlight potentially profound dependence effects: density some zooplankton species varied between significant negative effect one experiment to positive another, whereas other showed no another. review mechanisms could underlie having opposite same prey. findings illustrate observed may hold, even for system.

Language: Английский

---

When, where, and how prey pair antipredator behaviors to natural and anthropogenic mortality risks

Research Square (Research Square), Journal Year: 2025, Volume and Issue: unknown

Published: April 28, 2025

Background Behavioral responses of prey to predation risk have ecological impacts that can be as great direct mortality. Risk response involves either behavioral changes or spatial avoidance, but it is not clear how decide between these strategies. Theory often suggests pair risks based on the hunting mode (hunting hypothesis), may ignore prioritize responding most lethal predators (lethality hypothesis). Furthermore, respond distribution (risky places hypothesis) only during periods highest times Methods To test hypotheses, we evaluated white-tailed deer (Odocoileus virginianus) from two natural mesopredators and human sources Specifically, determined, for each source risk, whether responded with state avoidance this behavior changed time (diurnally annually). We collared tracked 40 female 29 male deer. determine collected data coyotes (Canis latrans), bobcats (Lynx rufus), modification, hunters, roads. used hidden Markov models (HMM) covariate impacted probability transitioning states selection functions (SSF) spatially avoided covariate. Results Generally, in both modification. In mesopredators, consistently shifted slower movement states. Spatial modification varied depending day. During daylight hours, selected crepuscular nighttime period, Conclusions Space use was strongly related more humans, providing support lethality hypothesis. Despite prioritizing state, suggesting still important behavior. Finally, temporal patterns align other studies indicate time-dependent, further highlight complex push-pull relationship modified areas wildlife.

Language: Английский

---

Effects of predation risks of bats on the growth, development, reproduction, and hormone levels of Spodoptera litura

Frontiers in Ecology and Evolution, Journal Year: 2023, Volume and Issue: 11

Published: April 17, 2023

Predation is a powerful selection pressure that shapes predator–prey interactions. Due to long-term interactions, moths have developed hearing detect the echolocation calls of bats. This allows bats impose non-consumptive effects predation on moths. However, information changes in growth, development, reproduction, and hormones are vulnerable bat limited. In this study, we used Spodoptera litura (Lepidoptera: Noctuidae) determine risks their hormone titers. Our results showed larvae S. increased food intake, accelerated development larval stages, mortality metamorphosis failure, had smaller body size under risk by Additionally, reproductive activity fecundity decreased adults , but juvenile titers 20-Ecdydysone increased. These suggested an adaptive response at cost lower survival reproduction. Finally, found different responses cues, which they might assess magnitude make most suitable decision for highlight importance imposed negatively regulate population dynamics findings indicated biological control bugs using promising strategy.

Language: Английский

---

Long-term anti-predator learning and memory differ across populations and sexes in an intertidal snail

Proceedings of the Royal Society B Biological Sciences, Journal Year: 2024, Volume and Issue: 291(2032)

Published: Oct. 1, 2024

Anti-predator behaviours in response to predator cues can be innate, or they learned through prior experience and remembered over time. The duration strength of continued anti-predator behaviour after are no longer present, the potential for an enhanced when re-exposed later is less known but could account observed variation responses. We measured carryover effects past predation exposure learning memory marine snail

Language: Английский

---

The primacy of density‐mediated indirect effects in a community of wolves, elk, and aspen

Ecological Monographs, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 23, 2024

Abstract The removal or addition of a predator in an ecosystem can trigger trophic cascade, whereby the indirectly influences plants and/or abiotic processes via direct effects on its herbivore prey. A cascade operate through density‐mediated indirect effect (DMIE), where reduces density predation, trait‐mediated (TMIE), induces trait response that modifies herbivore's plants. Manipulative experiments suggest TMIEs are equivalent more important driver cascades than DMIEs. Whether this applies generally nature is uncertain because few studies have directly compared magnitudes and DMIEs natural unmanipulated field patterns. TMIE often invoked to explain textbook involving wolves ( Canis lupus ), elk Cervus canadensis aspen Populus tremuloides ) northern Yellowstone National Park. This hypothesis posits increase recruitment young into overstory primarily reduced browsing spatial variation wolf predation risk rather population density. To test hypothesis, we spatiotemporal temporal patterns across 113 stands over 21‐year period (1999–2019) Only 2 10 indices had statistically meaningful aspen, these were 8–28 times weaker extent was attributable our results wolf–elk–aspen trait‐mediated. aligns with alternative other actively hunting predators broad habitat domains cause dominate whenever prey, such as elk, also domain. For at least type predator–prey community, study suggests risk‐induced responses be abstracted ignored while still achieving accurate understanding cascades.

Language: Английский

---

Playing it safe; risk‐induced trait responses increase survival in the face of predation

Journal of Animal Ecology, Journal Year: 2023, Volume and Issue: 92(3), P. 690 - 697

Published: Jan. 4, 2023

Abstract Predation risk effects are impacts on prey caused by predators that do not include consumption. These can changes in behaviour, physiology, and morphology (i.e. risk‐induced trait responses), which have consequences to individual fitness population dynamics non‐consumptive effects). While these responses (RITRs) lower as compared exposed risk, they assumed increase the presence of predators. much work has been built upon this assumption, most evidence occurs consumptive experiments where values consumed unknown. We little showing individuals with a greater magnitude RITR survival. Here, we tested hypothesis RITRs survival predators, but come at cost growth. using Nucella lapillus Carcinus maenas predator including mussels basal resource two‐phase mesocosm experimental set‐up. In phase 1, were placed into either control or treatment (exposure non‐lethal ) for 28 days their behaviour growth measured. 2, lethal was added all mesocosms (non‐lethal crabs removed), recorded 15 days. At (group) level, found predation 1 had significantly aversion (summed score risky vs. safe behaviour) level (regardless treatment), scores higher 2 when predator, came This study provides some first empirical evidence, both group testing long‐held assumption behavioural face direct predation, prey. results add our growing understanding benefits generally.

Language: Английский

---

Predator signaling of multiple prey on different trophic levels structures trophic cascades

Ecology, Journal Year: 2023, Volume and Issue: 104(6)

Published: April 9, 2023

Abstract The capacity of an apex predator to produce nonconsumptive effects (NCEs) in multiple prey trophic levels can create considerable complexity cascading interactions, but these are poorly studied. We examined such a model food web where the (blue crabs) releases chemical cues urine that affect both intermediate consumer (mud crabs seek shelter) and basal (oysters induced grow stronger shells). Shelter availability presence were manipulated laboratory experiment identify patterns species interactions. Then, experimentally uninduced oysters planted across high‐quality low‐quality habitats with varying shelter habitat heterogeneity determine consistency field. Oyster shell thickening response blue crab generally protected from mud predation field environments differed intensity, structural complexity, heterogeneity, composition. However, NCEs on (greater use refugia) opposed oyster interior reefs while still providing survival advantages reef edges bare substrates. Thus, combined changing movement predators morphological defenses complex, predictable, landscapes ecotones vary complexity. Generalist feed ubiquitous, their potential propagating simultaneously different must be quantified understand role webs.

Language: Английский

---

Prey responses to direct and indirect predation risk cues reveal the importance of multiple information sources

Journal of Animal Ecology, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 28, 2024

Abstract Prey can use several information sources (cues) to assess predation risk and avoid with a variety of behavioural responses (e.g., changes in activity, foraging, vigilance, social behaviour, space use, reproductive behaviour). Direct cues produced by predators indirect from environmental features or conspecific heterospecific prey generally provide different types about risk. Despite widespread interest understanding antipredator direct cues, clear general pattern relative response strength across taxa environments has yet emerge. We conducted meta‐analysis studies ( N = 113 articles 999 effect sizes taken search over 7500 articles) testing risk, their combination, terrestrial aquatic ecosystems. further contrasted if effects were moderated ecosystem type (terrestrial, marine, freshwater), cue source (predator, conspecific, heterospecific, feature), sensory modality (visual, auditory, chemosensory). Overall, there strong on behaviour. found that responded more strongly when both presented together compared either isolation, which was driven activity levels but not other behaviours. There no cues. Responses these interactions between environment, source, visual elicited stronger than modalities, chemosensory those predator systems). These results suggest rather broad framework the specific context system should be considered tests predictions how respond elucidate patterns responses.

Language: Английский

---