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Multispecies assemblages of Appalachian desmognathans have long intrigued ecologists seeking to understand the structure of ecological communities. Body size and life history in this group correlate with the moisture gradient from stream to forest, with large species being more aquatic and progressively smaller ones being ever more terrestrial. Since the work of N.G. Hairston, Sr. in the early 1980s, the prevailing hypothesis has been that predation and competition among desmognathans themselves have been the driving processes in the development and maintenance of the spatial organization along stream sides, with large, aggressive species forcing smaller ones to occupy less favorable terrestrial niches. Decades of research have confirmed that biotic interactions are important. However, evidence from recent studies has not agreed with the idea that biotic interactions are primary. Herein, I have concluded that the prevailing hypothesis fails to reconcile the currently available data. I have presented an alternative hypothesis that an abiotic factor, specifically the relative abundance of water, has been the primary force driving adaptation of species of Desmognathus longitudinally along moisture gradients by way of stream headwaters. Interspecific interactions, though important aspects of the current ecology of these species, are not the underlying drivers of spatial organization along the moisture gradient. I have further generated specific predictions that will enable this hypothesis to be tested. [ABSTRACT FROM AUTHOR]

In this paper, a predator–prey system with multiple anti-predator behaviors is developed and studied, where not only the prey may spread between patches but also the fear effect and counter-attack behavior of the prey are taken into account. First, the stability and existence of coexistence equilibria are presented. The unique positive equilibrium may be a saddle-node or a cusp of codimension 2. Then, various transversality conditions of bifurcations such as saddle-node bifurcation, transcritical bifurcation, Hopf bifurcation and Bogdanov–Takens bifurcation are obtained. Moreover, compared with a single strategy, the multiple anti-predator strategies are more beneficial to the persistence and the population density of prey. [ABSTRACT FROM AUTHOR]

This paper proposes a two-dimensional modified Leslie–Gower predator–prey model with carry-over effects, fear, prey protection and additional food, including prey harvesting. For this, it assumes the carry-over effect with delay incorporated in the birth rate of the prey population and gestation delay in Leslie–Gower term of a predator, and supposes that the predator consumes the prey according to Holling type II functional response. This dynamical system is split into two groups, namely non-delayed and delayed systems, respectively. In the non-delayed system, first, we discuss positivity, boundedness solutions, and the existence of equilibria, especially finding the coexistence of interior equilibrium points under certain conditions. After that, local and global stabilities are systematically analyzed. In addition, we obtain the conditions of Hopf-bifurcation in terms of the growth rate of prey species, prey protection and preference rate of predator for the non-delayed system. Whereas in the delayed system, both the delays have an essential role in governing the dynamical system discussed in three cases, and each case found the Hopf-bifurcation parameters for which the system changes stability behavior into instability. At last, the numerical simulations have been carried out to verify the theoretical findings. [ABSTRACT FROM AUTHOR]

An ecosystem with anti-predator behavior is established in both deterministic and stochastic environments. This means that adult prey could attack weak predators. Bifurcation diagrams are used to analyze the deterministic case, while a tool called the most probable trajectory, defined by the spatial extreme point of the probability density function (PDF), is employed to explore the stochastic case. The Fokker-Planck equation is solved using the stochastic averaging method of energy envelope, which provides an analytical expression for the PDF. The results show that in the deterministic case, effective anti-predator behavior can dampen predator-prey oscillations and mitigate negative effects caused by the time delay. Additionally, it can accelerate the transient solution to reach a steady state and reduce the ratio of predator-to-prey densities in coexistence. In the stochastic case, effective anti-predator behavior can raise the noise threshold that leads to population extinction. Furthermore, it can also reduce the randomness of solutions. It's worth noting that appropriate anti-predator behavior can ensure that the most probable solution in the stochastic system approximates the solution in the deterministic system. Monte Carlo simulations verify the accuracy of these analytical results. [ABSTRACT FROM AUTHOR]

Current environmental changes can drastically affect aquatic freshwater ecosystems. Salinization is one such change that affects freshwater species due to osmotic costs, which induce a wide variety of behavioural responses, including altered response to predation. This is particularly important in larval anurans, known to modulate their morphology, physiology and behaviour in response to salinity. Although these responses are known for long-term exposure, the effects of shorter exposure to salinity, relevant for coastal biodiversity as a result of sea water intrusions and precipitation variation, have rarely been assessed despite their importance in understanding the speed at which impacts on biodiversity occur. In this study, we experimentally acclimated larvae of the spined toad, Bufo spinosus , for 2 weeks to freshwater or to moderate levels of salinity (4 g/litre). The response to predation, activity and spatial movements of each individual were then assessed both at the salinity of acclimation and after a change in salinity. We demonstrated that medium-term exposure to salinity decreased activity, decreased growth and increased mortality. In contrast, sudden changes in salinity increased the escape distance of tadpoles in response to a predation stimulus but decreased activity. These results suggest that exposure to both stressors (predation cues and varying salinities) led to increased activity presumably linked to a stress response. However, individuals exposed to a change in salinity or to moderate salinity for medium durations expressed similar behavioural responses, indicating that the detrimental effects of high salinity can occur rapidly. Future studies should investigate the dynamics of osmolality in larval anurans exposed to brackish water to assess whether these behavioural shifts are linked with hydromineral dysregulation, and how long after exposure this occurs. • Two weeks exposure to salinity reduced tadpole growth and activity. • Transfer to freshwater did not improve activity levels. • Transfer to high salinity altered behaviour in less than 1 h. • Sudden increase in salinity led to increased escape distance from predators. • Sudden changes in salinity led to decreased overall activity. [ABSTRACT FROM AUTHOR]

Aposematic prey use conspicuous, high-contrast colour patterns to warn potential predators that they possess a defence mechanism, and signal uniformity is important to promote predator learning and memory retention; however, documented variation in the aposematic pattern of many species exists. Most aposematism studies use avian predators and insect prey; we know little about how mammalian predators learn about and interact with aposematic prey. For the first time, we evaluated aposematic learning in a mammalian predator–prey system. We conditioned captive coyotes, Canis latrans , to contact brown-furred models, and then trained them to avoid black-and-white models resembling striped skunks, Mephitis mephitis , that sprayed a skunk oil solution before testing their ability to generalize to variant patterns mimicking natural skunk coat variation. Coyotes exhibited great variation at all levels of the experiment but generally showed varying levels of wariness of the skunk-striped model and most effectively learned to avoid the model after being sprayed. Subsequently, whiter models elicited greater avoidance than blacker models, suggesting that the strength of the white on black signal influences coyote aposematic generalization. This pioneering study of mammalian aposematic learning suggests that more conspicuous coloration speeds learning for predator avoidance of aposematic prey and enhances generalization. • First examination of aposematic learning in a mammalian predator–prey system. • We trained coyotes to avoid skunk-striped models that sprayed skunk oil upon attack. • Coyotes displayed varying wariness of skunk-striped models. • Whiter models induced stronger avoidance than blacker models. • Pioneering study reveals coyotes' ability to learn avoidance from skunk models. [ABSTRACT FROM AUTHOR]

The process of organizing and interpreting sensory information, known as perceptual processing, is a key feature of adaptation allowing animals to integrate, assess and cope with challenges in their environments. Here, we examined the durations of vigilance bouts and stares in bighorn sheep, Ovis canadensis , as an indicator of time spent vigilant and perceptual processing, respectively. We tested the extent to which vigilance was shaped by relevant ecological factors, focusing on predation risk. Specifically, we tested whether stare duration increased when sheep were younger, part of smaller groups, further from others, further from escape terrain or closer to obstructive cover, all of which are expected to affect individual predation risk. Perceptual processing in bighorn sheep conformed to the 1–4 s perceptual window found in other mammals, consistent with the idea of a phylogenetically conserved mechanism across mammalian species but was variable within individuals, indicating that perceptual processing is plastic to relevant ecological contexts. As expected, stare duration was much shorter than vigilance bout duration. Stare duration increased with decreasing distance to obstructive cover, which could indicate perceptual processing costs of searching for cryptic predators. We also found a significant difference in vigilance bout duration between the sexes: age was positively correlated with vigilance bout duration in males but not in females. Vigilance bout durations were longer when animals were further from escape terrain. Neither group size nor distance to other individuals was associated with stare or bout durations. • We examined vigilance bouts and stares (perceptual processing) in bighorn sheep. • Vigilance bout duration was highly repeatable; stare duration was more variable. • Vigilance bouts were affected by age, sex and distance to escape terrain. • Stare duration was only affected by distance to obstructive cover. • Male, but not female, bighorn sheep increased vigilance bout duration with age. [ABSTRACT FROM AUTHOR]

Crested Caracaras (Caracara plancus) are diurnal, opportunistic raptors that feed on a great variety of prey, including carrion, nestlings, and eggs. In the coastal area of Chubut province, Argentina, they co-occur with White-headed Steamer-Ducks (Tachyeres leucocephalus), an endemic and vulnerable species. Here we report observations of Crested Caracaras on nests of White-headed Steamer-Ducks in the Interjurisdictional Marine Park in Northern San Jorge Gulf, Chubut, Argentina. We looked for steamerduck nests on islands and islets in the park from September to December in 2015 and 2016. We installed camera traps at 21 nests and operated them for a total of 166 camera-nights. We detected Crested Caracaras 27 times, at 15% and 37% of the duck nests in 2015 and 2016, respectively. We corroborated predation on eggs after visiting nests, although we were not able to see Caracaras directly eating eggs on pictures. The timing of Crested Caracara visits to duck nests corresponded with the recess pattern (i.e., periods of time when nest is unattended during incubation) of the White-headed Steamer-Ducks. Crested Caracaras are generally visual predators and they likely observe the steamerducks and take advantage of their incubation patterns. Our camera data contribute to improving our understanding of Crested Caracara ecology and potential limiting factors on White-headed Steamer-Duck nesting success. Caracara plancus es una rapaz oportunista de hábitos diurnos, que se alimenta de gran variedad de presas, carroña, pichones y huevos. En la costa marina de la provincia del Chubut (Argentina), se reproduce en simpatría y sintopía con el pato Tachyeres leucocephalus, una especie endémica y vulnerable. Aquí reportamos la presencia y el patrón de actividad de C. plancus sobre los nidos de T. leucocephalus en el Parque Interjurisdiccional Marino del norte del Golfo San Jorge (Chubut, Argentina). Durante septiembre y diciembre de 2015 y 2016 buscamos nidos de T. leucocephalus en las islas e islotes dentro del parque. A través del uso de cámaras trampa instaladas en 21 nidos por un período total de 166 nochescámara, registramos un total de 27 detecciones. Detectamos la presencia de C. plancus en el 15% y 37% de los nidos en 2015 y 2016, respectivamente. Corroboramos la depredación de los huevos con nuestras visitas, pero no pudimos ver directamente en las fotos a C. plancus comiendo huevos. El momento de las visitas de C. plancus a los nidos de patos coincidió con el patrón de recesos de T. leucocephalus. C. plancus es generalmente un depredador visual y probablemente observó a T. leucocephalus y aprovechó sus patrones de incubación. Nuestros datos de las cámaras contribuyen a mejorar nuestra comprensión de la ecología de C. plancus y los posibles factores que limitan el éxito reproductivo de T. leucocephalus. [Traducción de los autores editada] [ABSTRACT FROM AUTHOR]

Consistent differences among individuals in the boldness-shyness continuum have been described in a variety of species. Environments with higher levels of predation are likely to select for shyer behavioural responses, due to the increased susceptibility of being 'fearless' in a high-risk environment. In this study, we compared the behavioural responses in two populations of South Island robin (Petroica australis), one of which is sympatric with a range of introduced predators (Kaikoura mainland) and one with no introduced predators (Motuara Island). We found robins on Motuara Island were significantly bolder than mainland robins. This was evidenced by robins in this low-risk environment being more likely to approach mealworms placed closer to a researcher. Robins in Kaikoura were also significantly slower than Motuara Island robins in latency (time to approach mealworms) but faster to remove five mealworms placed nearest to a researcher (handling time). These differences may be driven by bolder individuals having a disadvantage on the mainland as it exposes them to a higher risk from introduced predators. Although the extent to which these differences have a genetic basis is unknown, our results suggest that sympatry with introduced predators may favour more risk-averse behaviours in robins and other native species. [ABSTRACT FROM AUTHOR]

Artificial light at night (ALAN) is considered a growing threat to bat species due to its potential impacts on circadian cycles, increased predation risk, and avoidance behaviour. Urban expansion and associated increases in ALAN may impact the behaviour of New Zealand's critically threatened long-tailed bat (Chalinolobus tuberculatus). To determine whether long-tailed bat behaviour was affected by ALAN, a small-scale study was conducted on the fringe of Hamilton City, New Zealand, using LED floodlights. Changes in the number of nightly detections in response to periodic illumination were measured using acoustic monitoring and compared to a nearby unlit control site. Bat detection rates were significantly lower on lit nights compared to unlit nights at the treatment site, while there was no significant difference at the control site for the same period. In addition, the median time of the first recorded bat detection was c. 2 h later during lit nights compared to unlit nights at the treatment site. These results indicate that ALAN may have a negative effect on the behaviour of long-tailed bats, potentially delaying the use of areas and excluding them from foraging habitat. Further research into the effects and potential mitigation of ALAN for long-tailed bats is required. [ABSTRACT FROM AUTHOR]

Aim: Spatial variation in predation can shape geographic patterns in ecology and evolution, but testing how predation varies across ecosystems is challenging as differing species compositions and defensive adaptations can mask underlying patterns. Recently, biogeography has borrowed a tool from ecology: clay prey models. But clay models have not been adequately tested for geographic comparisons, and a well‐known problem –that clay prey only appeal to a subset of potential predators– could bias detected geographic patterns whenever the relative importance of predator guilds varies among sites. Here, we test whether clay larvae accurately capture geographic differences in predation on real larvae. Location: 90° of latitude and >2000 m elevation across the Americas. Taxon: Vertebrate and invertebrate predation on 'superworms' (Zophobas larvae). Methods: Across six sites that vary dramatically in latitude, elevation, and biome, we quantified predation on live, dead, and clay larvae. We physically excluded vertebrate predators from some larvae to distinguish total predation and invertebrate‐only predation. Results: Predation on live superworms almost doubled from our high‐elevation high‐latitude site to our low‐elevation tropical site. Geographic patterns were consistent among live and dead larvae, but clay larvae missed extremely high predation at some sites and therefore mis‐measured true geographic patterns. Clay larvae did a particularly bad job at capturing geographic patterns in predation by invertebrates, although sample sizes for invertebrate predation were small. Main Conclusions: Clay larvae are inappropriate for comparing predation rates across sites. They should be abandoned for biogeographic studies and reserved for comparisons within, rather than across, predator communities. [ABSTRACT FROM AUTHOR]

Aim: Climate is a major driver of large‐scale variability in biodiversity, as a likely result of more intense biotic interactions under warmer conditions. This idea fuelled decades of research on plant‐herbivore interactions, but much less is known about higher‐level trophic interactions. We addressed this research gap by characterizing both bird diversity and avian predation along a climatic gradient at the European scale. Location: Europe. Taxon: Insectivorous birds and pedunculate oaks. Methods: We deployed plasticine caterpillars in 138 oak trees in 47 sites along a 19° latitudinal gradient in Europe to quantify bird insectivory through predation attempts. In addition, we used passive acoustic monitoring to (i) characterize the acoustic diversity of surrounding soundscapes; (ii) approximate bird abundance and activity through passive acoustic recordings; and (iii) infer both taxonomic and functional diversity of insectivorous birds from recordings. Results: The functional diversity of insectivorous birds increased with warmer climates. Bird predation increased with forest cover and bird acoustic activity but decreased with mean annual temperature and functional richness of insectivorous birds. Contrary to our predictions, climatic clines in bird predation attempts were not directly mediated by changes in insectivorous bird diversity or acoustic activity, but climate and habitat still had independent effects on predation attempts. Main Conclusions: Our study supports the hypothesis of an increase in the diversity of insectivorous birds towards warmer climates but refutes the idea that an increase in diversity would lead to more predation and advocates for better accounting for activity and abundance of insectivorous birds when studying the large‐scale variation in insect‐tree interactions. [ABSTRACT FROM AUTHOR]

Roads have pervasive impacts on wildlife, including habitat loss and fragmentation, road mortality, habitat pollution and increased human use of habitats surrounding them. However, the effects of roads on interspecific interactions are less understood. Here we provide a synthesis of the existing literature on how species interactions may be disrupted by roads, identify knowledge gaps, and suggest avenues for future research and conservation management. We conducted a systematic search using the Web of Science database for each species interaction (predation, competition, mutualism, parasitism, commensalism and amensalism). These searches yielded 2144 articles, of which 195 were relevant to our topic. Most of these studies focused on predation (50%) or competition (24%), and less frequently on mutualism (17%) or, parasitism (9%). We found no studies on commensalism or amensalism. Studies were biased towards mammals from high‐income countries, with most conducted in the USA (34%) or Canada (18%). Our literature review identified several patterns. First, roads disrupt predator–prey relationships, usually with negative impacts on prey populations. Second, new disturbed habitats created in road corridors often benefit more competitive species, such as invasive species, although some native or endangered species can also thrive there. Third, roads degrade mutualistic interactions like seed dispersal and pollination. Fourth, roads can increase parasitism rates, although the intensity of the alteration is species specific. To reduce the negative impacts of roads on interspecific interactions, we suggest the following management actions: (i) verges should be as wide and heterogenous as possible, as this increases microhabitat diversity, thus enhancing ecosystem services like pollination and seed dispersal; (ii) combining different mowing regimes can increase the complexity of the habitat corridor, enabling it to act as a habitat for more species; (iii) the use of de‐icing salts should be gradually reduced and replaced with less harmful products or maintenance practices; (iv) wildlife passes should be implemented in groups to reduce animal concentrations inside them; (v) periodic removal of carcasses from the road to reduce the use of this resource by wildlife; and (vi) implementation of traffic‐calming schemes could enhance interspecific interactions like pollination and avoid disruption of predator–prey relationships. [ABSTRACT FROM AUTHOR]

Predation is a dominant structuring force in ecological communities. In aquatic environments, predation on bivalves has long been an important focal interaction for ecological study because bivalves have central roles as ecosystem engineers, basal components of food webs, and commercial commodities. Studies of bivalves are common, not only because of bivalves' central roles, but also due to the relative ease of studying predatory effects on this taxonomic group. To understand patterns in the interactions of bivalves and their predators we synthesised data from 52 years of peer‐reviewed studies on bivalve predation. Using a systematic search, we compiled 1334 studies from 75 countries, comprising 61 bivalve families (N = 2259), dominated by Mytilidae (29% of bivalves), Veneridae (14%), Ostreidae (8%), Unionidae (7%), and Dreissenidae and Tellinidae (6% each). A total of 2036 predators were studied, with crustaceans the most studied predator group (34% of predators), followed by fishes (24%), molluscs (17%), echinoderms (10%) and birds (6%). The majority of studies (86%) were conducted in marine systems, in part driven by the high commercial value of marine bivalves. Studies in freshwater ecosystems were dominated by non‐native bivalves and non‐native predator species, which probably reflects the important role of biological invasions affecting freshwater biodiversity. In fact, while 81% of the studied marine bivalve species were native, only 50% of the freshwater species were native to the system. In terms of approach, most studies used predation trials, visual analysis of digested contents and exclusion experiments to assess the effects of predation. These studies reflect that many factors influence bivalve predation depending on the species studied, including (i) species traits (e.g. behaviour, morphology, defence mechanisms), (ii) other biotic interactions (e.g. presence of competitors, parasites or diseases), and (iii) environmental context (e.g. temperature, current velocity, beach exposure, habitat complexity). There is a lack of research on the effects of bivalve predation at the population and community and ecosystem levels (only 7% and 0.5% of studies respectively examined impacts at these levels). At the population level, the available studies demonstrate that predation can decrease bivalve density through consumption or the reduction of recruitment. At the community and ecosystem level, predation can trigger effects that cascade through trophic levels or effects that alter the ecological functions bivalves perform. Given the conservation and commercial importance of many bivalve species, studies of predation should be pursued in the context of global change, particularly climate change, acidification and biological invasions. [ABSTRACT FROM AUTHOR]

Interspecific information flow is known to affect individual fitness, population dynamics and community assembly, but there has been less study of how species diversity affects information flow and thereby ecosystem functioning and services. We address this question by first examining differences among species in the sensitivity, accuracy, transmissibility, detectability and value of the cues and signals they produce, and in how they receive, store and use information derived from heterospecifics. We then review how interspecific information flow occurs in communities, involving a diversity of species and sensory modes, and how this flow can affect ecosystem‐level functions, such as decomposition, seed dispersal or algae removal on coral reefs. We highlight evidence that some keystone species are particularly critical as a source of information used by eavesdroppers, and so have a disproportionate effect on information flow. Such keystone species include community informants producing signals, particularly about predation risk, that influence other species' landscapes of fear, and aggregation initiators creating cues or signals about resources. We suggest that the presence of keystone species means that there will likely be a positive relationship in many communities between species diversity and information through a 'sampling effect', in which larger pools of species are more likely to include the keystone species by chance. We then consider whether the number and relative abundance of species, irrespective of the presence of keystone species, matter to interspecific information flow; on this issue, the theory is less developed, and the evidence scant and indirect. Higher diversity could increase the quantity or quality of information that is used by eavesdroppers because redundancy increases the reliability of information or because the species provide complementary information. Alternatively, there could be a lack of a relationship between species diversity and information if there is widespread information parasitism where users are not sources, or if information sourced from heterospecifics is of lower value than that gained personally or sourced from conspecifics. Recent research suggests that species diversity does have information‐modulated community and ecosystem consequences, especially in birds, such as the diversity of species at feeders increasing resource exploitation, or the number of imitated species increasing responses to vocal mimics. A first step for future research includes comprehensive observations of information flow among different taxa and habitats. Then studies should investigate whether species diversity influences the cumulative quality or quantity of information at the community level, and consequently ecosystem‐level processes. An applied objective is to conserve species in part for their value as sources of information for other species, including for humans. [ABSTRACT FROM AUTHOR]

Motion is a crucial part of the natural world, yet our understanding of how animals avoid predation whilst moving remains rather limited. Although several theories have been proposed for how antipredator defence may be facilitated during motion, there is often a lack of supporting empirical evidence, or conflicting findings. Furthermore, many studies have shown that motion often 'breaks' camouflage, as sudden movement can be detected even before an individual is recognised. Whilst some static camouflage strategies may conceal moving animals to a certain extent, more emphasis should be given to other modes of camouflage and related defences in the context of motion (e.g. flicker fusion camouflage, active motion camouflage, motion dazzle, and protean motion). Furthermore, when motion is involved, defence strategies are not necessarily limited to concealment. An animal can also rely on motion to mislead predators with regards to its trajectory, location, size, colour pattern, or even identity. In this review, we discuss the various underlying antipredator strategies and the mechanisms through which they may be linked to motion, conceptualising existing empirical and theoretical studies from two perspectives – concealing and misleading effects. We also highlight gaps in our understanding of these antipredator strategies, and suggest possible methodologies for experimental designs/test subjects (i.e. prey and/or predators) and future research directions. [ABSTRACT FROM AUTHOR]

Individuals join mixed‐species groups to gain benefits such as improved foraging and predator detection. Birds in the family Paridae often drive mixed‐species flocking in North America, and these species can act as community informants for forest‐wide eavesdropping networks. Although we know a great deal about how this communication functions in anti‐predator contexts, less is known about how the vocalizations of members of these flocks may affect the foraging behavior of potential flockmates. In this study, we presented naturally occurring mixed‐species flocks of chickadees, titmice, and nuthatches with one of four playback conditions: chickadee‐only calls, nuthatch‐only calls, calls of both species, and a silent control. We hypothesized that the flocks would be most responsive to playbacks that contained calls from more than one species. We also tested an alternative hypothesis that predicted that birds would be most responsive to the nuclear species within the flock (chickadees). We found that birds were more likely to arrive, and arrived more quickly, for the playbacks with calls from both species compared to playbacks of nuthatches alone or the silent control. Playbacks of chickadee calls alone attracted an intermediate number of birds, which did not differ significantly from the mixed‐species flock condition, or the nuthatch call alone condition. Our hypotheses were not supported due to the lack of significant difference between the mixed‐species playbacks and the chickadee playbacks. However, our findings do indicate that different species in these flocks can react differently to the calls of members of these flocks and that future studies may continue to find asymmetries in attraction to these different social signals. [ABSTRACT FROM AUTHOR]

This special issue comprises papers presented at the 7th International Entomophagous Insects Conference (IEIC7), in Buenos Aires, Argentina, in 2023. Entomophagous insects, which prey on or parasitize other insects, play a pivotal role in ecosystems and are widely utilized as biocontrol agents. This special issue includes two review articles and nine research papers covering diverse subjects such as ecology, physiology, behavior, genetics, chemical ecology, and biological control, which reflects the diversity of topics presented and discussed during the conference. [ABSTRACT FROM AUTHOR]

The mealybug (Paracoccus marginatus) is one of the most important pests of papaya (Carica papaya L.). The high potential damage of this pest threatens papaya production. The objective of this paper is to explore the impact of biocontrol and temperature variations on the population dynamics of Paracoccus marginatus (P. marginatus). We first propose and study a mathematical model for the dynamics of P. marginatus within a papaya field. This model consists of a time-delayed non-autonomous system of differential equations that takes into account the egg incubation period, temperature variations, plant compensation and predators that are natural enemies of the papaya pest. We provide the basic properties of the model, compute the basic offspring number N 0 and show that there exists two threshold parameters N _ 0 and ξ 0 such that N _ 0 ≤ N 0 ≤ ξ 0 ≤ 1 and N 0 ≥ N _ 0 > 1 provide conditions for the extinction and persistence of the pest within the papaya field, respectively. After, we investigate the impact of biocontrol on the pest population. We found that the use of a control strategy based on constant releases of predators could reduce the pest population by 35.62 percent and increase the biomass by 77.50 percent, while the use of impulsive releases of predators result in a decrease of 96.31 percent of the pest population and an increases of 55.74 percent of the biomass. We also combine the use of continuous predator releases and bio-pesticides and discovered that a spray applied 90 days after germination could completely eliminate the pest population and boost the biomass by 81.58 percent. • The population dynamics of Paracoccus marginatus , papaya pest is modeled. • The model includes the egg incubation period, temperature variations and biocontrol. • The warm temperatures are favorable to the development and survival of the pest. • The use of impulsive releases of predators can reduce the pest by 96.31%. • The use of continuous releases of predators and bio-pesticides can eradicate the pest. [ABSTRACT FROM AUTHOR]

Allee effect in models in interacting species of predator prey system has great significance in ecological context. Allee effect plays crucial role in population dynamics in ecology, where it is the challenging fact that per capita population growth rate is positively dependent on the population density of a species. In this paper, we inspect the famous Hastings and Powell (HP) (Hastings and Powell 1991 Ecology 72 896–903) model incorporating component Allee effect on top predator's reproduction. We analyse the updated model with the help of both analytical and numerical phenomena. Considering cost of Allee effect, half-saturation constant of prey as the key parameters, the Hopf bifurcations are also analysed. The directions of Hopf bifurcations at the critical values of Allee parameter and half-saturation constant of prey are studied theoretically by using normal form theory introduced by Hassard et al (1981 Theory and Applications of Hopf Bifurcation vol 41 (CUP Archive)). The formulated model indicates that the system demonstrates chaotic, periodic and stable dynamics in the variation of key parameters. The chaos can be controlled for proper application of the large values of parameter used as the cost of Allee effect and also for small values of the parameter used as the half saturation constant of prey population. The results of this study are applicable in the field of marine and wild ecosystem dynamics. [ABSTRACT FROM AUTHOR]

The effects of forest fragmentation on ecosystems are pervasive, but little is known about the factors that influence lizard abundance in fragmented landscapes. We studied the roles of patch size and shape, thermal quality, and refuge availability as predictors of the relative abundance of Psammodromus algirus lizards at deciduous or evergreen forest fragments surrounded by cereal fields. Relative abundance, based on time-controlled counts, decreased from the northeast (dominated by deciduous habitat) to the southwest (with a higher cover of croplands, and dominated by evergreen habitat). Refuge availability was correlated with this gradient, decreasing from the northeast to the southwest and being larger in deciduous than in evergreen fragments. After controlling for the effects of this environmental variation, lizard abundance increased as perimeter-to-area ratio (P/A) decreased (and consequently as fragment size increased). Although the effects of thermal quality as such were negligible, our results can be interpreted in the light of thermoregulatory requirements; given the low temperatures available at shaded locations, lizards should actively select sunlit patches while they try to minimize predation risk by basking as close as possible to the nearest refuge. Although use of fragment edges as basking sites is expected to increase with P/A ratio, lizards should avoid using them as basking sites, because both exposure to predators and risk of overheating are expected to be higher at edges and croplands than inside fragments. We conclude that long and narrow forest strips with high P/A ratios could act as ecological traps rather than as dispersion-promoting corridors. [ABSTRACT FROM AUTHOR]

Interspecific interactions, including predator–prey, intraguild predation (IGP) and competition, may drive distribution and habitat use of predator communities. However, elucidating the relative importance of these interactions in shaping predator distributions is challenging, especially in marine communities comprising highly mobile species. We used individual‐based models (IBMs) to predict the habitat distributions of apex predators, intraguild (IG) prey and prey. We then used passive acoustic telemetry to test these predictions in a subtropical marine predator community consisting of eight elasmobranch (i.e. shark and ray) species in Bimini, The Bahamas. IBMs predicted that prey and IG prey will preferentially select habitats based on safety over resources (food), with stronger selection for safe habitat by smaller prey. Elasmobranch space‐use patterns matched these predictions. Species with predator–prey and asymmetrical IGP (between apex and small mesopredators) interactions showed the clearest spatial separation, followed by asymmetrical IGP among apex and large mesopredators. Competitors showed greater spatial overlap although with finer‐scale differences in microhabitat use. Our study suggests space‐use patterns in elasmobranchs are at least partially driven by interspecific interactions, with stronger spatial separation occurring where interactions include predator–prey relationships or IGP. [ABSTRACT FROM AUTHOR]

The common hippopotamus (Hippopotamus amphibius) is one of the most endangered mega herbivore in Africa. Although the human-hippo conflict (HHC) is currently escalating due to habitat loss, little is known about the scope of the conflict and potential mitigation measures. From 2021 to 2022, the extent of HHC, the perception of local inhabitants towards the animal, and its impacts on the conservation of the hippo were assessed within and in the surrounding areas of Dhidhessa Wildlife Sanctuary, southwestern Ethiopia. A total of 227 households were used as a data sources, participating in the questionnaire survey, focus group discussion and key informant interviews. Direct field observations were also used as key data source. Crop raiding and damage (63%, n = 143), was the most severely reported source of conflict, followed by direct human attack (22.9%, n = 52). Livestock predation and increased hippo mortality were also common types of HHC in the area. According to the study, the majority of respondents (74.4%, n = 169) agreed that the trend of conflict was increasing, while 16.7% (n = 38) argued that there was no change. Food scarcities in the buffer zone, as well as agricultural expansion in the area, have been identified as major drivers of HHC. The majority of respondents had a negative attitude toward hippo conservation; however, there were differences based on gender, age, and educational level. The major traditional hippo conflict mitigation strategies in the area include guarding, fencing, and trenching. Field observation revealed that a large extent of the former grazing and ranging areas of hippo in the area are heavily encroached and taken over by large private and public agricultural investments. Vacating and recovering at least the former buffer areas dedicated to the wildlife in the area and modern, non-lethal mitigation strategies are recommended for better conservation and safeguarding of the currently good-sized hippo population of the sanctuary. [ABSTRACT FROM AUTHOR]

Camouflage is a widespread and well-studied anti-predator strategy, yet identifying which patterns provide optimal protection in any given scenario remains challenging. Besides the virtually limitless combinations of colours and patterns available to prey, selection for camouflage strategies will depend on complex interactions between prey appearance, background properties and predator traits, across repeated encounters between co-evolving predators and prey. Experiments in artificial evolution, pairing psychophysics detection tasks with genetic algorithms, offer a promising way to tackle this complexity, but sophisticated genetic algorithms have so far been restricted to screen-based experiments. Here, we present methods to test the evolution of colour patterns on physical prey items, under selection from wild predators in the field. Our techniques expand on a recently-developed open-access pattern generation and genetic algorithm framework, modified to operate alongside artificial predation experiments. In this system, predators freely interact with prey, and the order of attack determines the survival and reproduction of prey patterns into future generations. We demonstrate the feasibility of these methods with a case study, in which free-flying birds feed on artificial prey deployed in semi-natural conditions, against backgrounds differing in three-dimensional complexity. Wild predators reliably participated in this experiment, foraging for 11 to 16 generations of artificial prey and encountering a total of 1,296 evolved prey items. Changes in prey pattern across generations indicated improvements in several metrics of similarity to the background, and greater edge disruption, although effect sizes were relatively small. Computer-based replicates of these trials, with human volunteers, highlighted the importance of starting population parameters for subsequent evolution, a key consideration when applying these methods. Ultimately, these methods provide pathways for integrating complex genetic algorithms into more naturalistic predation trials. Customisable open-access tools should facilitate application of these tools to investigate a wide range of visual pattern types in more ecologically-relevant contexts. [ABSTRACT FROM AUTHOR]

Simple Summary: In this study, we investigated how predators and conspecific density impact the growth of Chinhai spiny newt larvae. Using a two-factor experimental design, we manipulated both factors to explore their independent and interactive effects on larval development. Our findings demonstrate that both high and low conspecific densities constrain larval growth, while predators also limit growth. Interestingly, high conspecific density restricts predator-induced growth plasticity without interacting effects. This study provides valuable insights into the complex interplay between environmental factors and larval development in endangered Chinhai spiny newts. Understanding these dynamics is crucial for informing conservation strategies aimed at protecting this vulnerable species. Predators significantly influence amphibian larval development. Predator-induced plasticity is often studied independently from conspecific density effects, but these environmental factors may interact. We conducted two-factor factorial experimental design to manipulate conspecific density and predator cues, aiming to investigate the independently or interactive impacts of these two factors on the development of Chinhai spiny newt larvae (Echinotriton chinhaiensis). Our findings reveal that both high and low conspecific densities constrain spiny newt larval growth and predators also limit growth. Interestingly, high conspecific density restricts predator-induced growth plasticity without interacting effects. Only lower density groups exhibit slower growth responses to predators. Our study investigates how density mediates predator-induced plasticity in the endangered Chinhai spiny newt larvae, providing insights into their intricate life history. These results contribute to the understanding of predator-induced plasticity in amphibians and provide insights into the adaptive strategies of endangered species like Chinhai spiny newt. Such knowledge informs the development of effective conservation strategies for their protection. [ABSTRACT FROM AUTHOR]

Simple Summary: Having venom is a rare trait among mammals and even rarer among primates. Slow and pygmy lorises are the only venomous primates, and they possess a unique "two-step" venom system. When threatened, they release a secretion from a gland on their forearm and lick it, activating the venom by mixing it with their saliva. There are several hypotheses for why slow and pygmy lorises evolved this unique trait. Venom can be used to capture prey, to defend against predators or parasites, or for competition with other slow or pygmy lorises. We tested the hypothesis that venom is used to capture prey by experimentally offering various arthropod prey items to 22 wild-caught greater slow lorises living in a rescue center. We observed how their behavior was affected by prey characteristics including size, potential for escape, and toxicity. The few venom-related behaviors we observed only occurred in a defensive context, suggesting that the greater slow lorises do not use their venom as a means of subduing prey. These negative results are consistent with the growing body of evidence that pygmy and slow lorises primarily use venom in competition with members of their own species. 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. [ABSTRACT FROM AUTHOR]

This article deals with a free boundary problem of the Lotka-Volterra type prey-predator model with advection in one space dimension. The model considered here may be applied to describe the expanding of an invasive or new predator species adopting a combination of random movement and advection upward or downward along the resource gradient, with the free boundaries representing expanding fronts of predator species. The main purpose of this article is to understand the influence of the advection environment on the dynamics of the model. We provide sufficient conditions for spreading and vanishing of the predator species, and we find a sharp threshold between the spreading and vanishing concerning this model. Moreover, for the case of successful spreading for the predator, we give estimates of asymptotic spreading speeds and nonlocal long-time behavior of the prey and the predator. [ABSTRACT FROM AUTHOR]

The human inclination to value rarity contributes to the exploitation of many wildlife species by driving up their market value when their numbers are scarce. This research investigates a model to explore how the value attached to rarity impacts the harvesting of predator species and subsequently influences the dynamics of predator-prey interactions in an ecological system. To broaden the model's scope, it's extended to its nonautonomous form by allowing the harvesting rate of predator species and the degree of neutrality in consumers to respond for the rarity of predator species to change over time. Both the autonomous and nonautonomous systems are explored through analytical and numerical investigation. Numerical findings reveal that as the prey population's growth rate gradually increases, the unforced system shifts from stable boundary equilibrium (harvesting absent) to stable interior equilibrium, then to oscillatory interior equilibrium, followed by period doubling oscillations leading to chaotic behavior. The autonomous system exhibits limit cycle oscillations around the boundary equilibrium when predator species are minimally harvested. Moderate harvesting stabilizes the system, while excessive harvesting induces instability. However, the chaotic oscillations can be eliminated through period-halving route upon decreasing the consumers' response to predator rarity. Furthermore, the seasonally forced model demonstrates periodic solutions, higher order periodic solutions, and chaotic dynamics contingent upon different settings of prey growth rate, the strength of seasonality in predator harvesting, and the consumers' response to predator rarity. [ABSTRACT FROM AUTHOR]

In this investigation, we explore a predator-prey system characterized by generalist predators exhibiting cooperative behavior during hunting, subject to nonlinear harvesting rate. Employing a Beverton-Holt type functional response to capture the impact of additional food sources on predator growth, our numerical findings affirm the destabilizing influence of hunting cooperation, excessive predation, and supplementary food sources. Conversely, the system demonstrates stabilization in response to increased prey species growth. We unveil the occurrence of both forward and backward bifurcations in the system due to the predator growth attributed to additional food sources, contingent on the degree of hunting cooperation. To broaden the scope, we extend our proposed model to its stochastic counterpart, introducing environmental white noises. Our numerical results anticipate that higher intensities of white noises lead to fluctuations of greater amplitude, while smaller intensities exhibit a more modest impact. Additionally, we elucidate the dynamics of prey and predator populations through histogram plots. The theoretical and numerical insights derived from this study provide a deeper understanding of the intricate dynamics within predator-prey systems of ecological communities, emphasizing the significance of additional food sources for cooperative predators subject to harvesting in both constant and fluctuating environments. [ABSTRACT FROM AUTHOR]

In this paper, the dynamical behaviors of a stochastic eco-epidemic predator-prey model with Lévy jump and Allee effect for prey population are investigated. First, the existence and uniqueness of the global positive solution are built. Then, the long-term behaviors of the prey and predator populations are obtained. Furthermore, we demonstrate the stochastic ultimate boundedness of all species and the ergodic stationary distribution without Lévy jump. Finally, numerical examples are provided to support the theoretical analysis results. [ABSTRACT FROM AUTHOR]

The structure of many aquatic food webs is influenced by tadpole survivorship and duration of seasonal occupancy, which depend on tadpole diet. Pollen has been occasionally reported to occur in tadpole diets, and the available studies show that tadpoles have a strong preference for this supposedly nutritive resource. Thus, we aimed to test whether a diet composed of pollen from varied plant species would boost tadpole growth, development, and agility/mobility, compared to a regular artificial balanced and nutritive diet. Tadpoles in initial developmental stages 25 and 30 grew more when fed with pollen, compared to artificial food and a mixture of both diets. Those initially in stage 30 advanced more developmental stages during one month when fed exclusively with pollen. Tadpoles fed with pollen moved longer distances in response to an aversive stimulus simulating a predatory attack than tadpoles fed with artificial food or a mixed diet. Our results corroborate the hypotheses of pollen being a very important food source to aquatic consumers such as tadpoles, being likely to influence the structure of aquatic food webs through tadpole nutrition and modulation of growth/development speed, as well as tadpole ability to escape predators. [ABSTRACT FROM AUTHOR]

This paper examines the dynamic behavior of a particular category of discrete predator-prey system that feature both fear effect and refuge, using both analytical and numerical methods. The critical coefficients and properties of bifurcating periodic solutions for Flip and Hopf bifurcations are computed using the center manifold theorem and bifurcation theory. Additionally, numerical simulations are employed to illustrate the bifurcation phenomenon and chaos characteristics. The results demonstrate that period-doubling and Hopf bifurcations are two typical routes to generate chaos, as evidenced by the calculation of the maximum Lyapunov exponents near the critical bifurcation points. Finally, a feedback control method is suggested, utilizing feedback of system states and perturbation of feedback parameters, to efficiently manage the bifurcations and chaotic attractors of the discrete predator-prey model. [ABSTRACT FROM AUTHOR]

This article proposes a class of nonsmooth Filippov pest–predator ecosystems with intermittent control strategies based on the pest's antipredator behavior. aiming to investigate the influence of control strategies and switching thresholds on pest control. First, a comprehensive theoretical analysis of various equilibria within the Filippov system is undertaken, emphasizing the presence and stability of sliding mode dynamics and pseudoequilibrium. Secondly, through numerical simulations, the article discusses boundary-focus, boundary-node, and boundary-saddle bifurcation. Finally, the nonexistence of limit cycles in the Filippov system is theoretically studied. The research indicates that the solution trajectories of the model ultimately stabilize either at the real equilibria or at pseudoequilibrium on the model's switching surface. Moreover, when the model has multiple coexisting real equilibrium and pseudoequilibrium, the pest-control strategy is correlated with the initial density of both the pest and the predator population. [ABSTRACT FROM AUTHOR]

The distribution of New Zealand sea lions is typically localised to New Zealand and its remote subantarctic islands. However, non-resident male sea lions were seen on Macquarie Island, 650 km from their nearest natal islands, in all months of all years from 1965 to 1980. The majority of the apparently opportunistic sightings were at the northern end of the island. Sightings increased from May to a September-October peak that was coincident with the cessation of breeding activities in the sea lions’ natal range and the period when resident gentoo and royal penguins, and fur and elephant seals aggregated for breeding, all of which are now confirmed prey for New Zealand sea lions on Macquarie Island. The long-term effect of predation pressure from New Zealand sea lions on resident species remains unmeasured. After sleeping, interacting with southern elephant seals was a core sea lion activity. Predation on seabirds and interactions with elephant seals increase the risk of cross-species disease transmission. [ABSTRACT FROM AUTHOR]

The risk of predation directly affects the physiology, behavior, and fitness of wild birds. Strong social connections with conspecifics could help individuals recover from a stressful experience such as a predation event; however, competitive interactions also have the potential to exacerbate stress. Few studies have investigated the interaction between environmental stressors and the social landscape in wild bird populations. In 2 years of field studies, we experimentally simulated predation attempts on breeding female tree swallows (Tachicyneta bicolor). At the same time, we manipulated female breast plumage color, a key social signal. Simulated predation events on tree swallows early in the nestling period reduced young nestlings' mass by approximately 20% and shortened telomere lengths. Ultimately, only 31% of nestlings in the predation group fledged compared with 70% of control nestlings. However, the effects of experimental manipulations were timing dependent: the following year when we swapped the order of the experimental manipulations and simulated predation during incubation, there were no significant effects of predation on nestling condition or fledging success. Contrary to our expectations, manipulation of the social environment did not affect the response of tree swallows to simulated predation. However, manipulating female plumage during the nestling period did reduce nestling skeletal size and mass, although the effects depended on original plumage brightness. Our data demonstrate that transient stressors on female birds can have carry‐over effects on their nestlings if they occur during critical periods in the breeding season. [ABSTRACT FROM AUTHOR]

The emergence of multicellularity is one of the major transitions in evolution that happened multiple times independently. During aggregative multicellularity, genetically potentially unrelated lineages cooperate to form transient multicellular groups. Unlike clonal multicellularity, aggregative multicellular organisms do not rely on kin selection instead other mechanisms maintain cooperation against cheater phenotypes that benefit from cooperators but do not contribute to groups. Spatiality with limited diffusion can facilitate group selection, as interactions among individuals are restricted to local neighbourhoods only. Selection for larger size (e.g. avoiding predation) may facilitate the emergence of aggregation, though it is unknown, whether and how much role such selection played during the evolution of aggregative multicellularity. We have investigated the effect of spatiality and the necessity of predation on the stability of aggregative multicellularity via individual-based modelling on the ecological timescale. We have examined whether aggregation facilitates the survival of cooperators in a temporally heterogeneous environment against cheaters, where only a subset of the population is allowed to periodically colonize a new, resource-rich habitat. Cooperators constitutively produce adhesive molecules to promote aggregation and propagule-formation while cheaters spare this expense to grow faster but cannot aggregate on their own, hence depending on cooperators for long-term survival. We have compared different population-level reproduction modes with and without individual selection (predation) to evaluate the different hypotheses. In a temporally homogeneous environment without propagule-based colonization, cheaters always win. Predation can benefit cooperators, but it is not enough to maintain the necessary cooperator amount in successive dispersals, either randomly or by fragmentation. Aggregation-based propagation however can ensure the adequate ratio of cooperators-to-cheaters in the propagule and is sufficient to do so even without predation. Spatiality combined with temporal heterogeneity helps cooperators via group selection, thus facilitating aggregative multicellularity. External stress selecting for larger size (e.g. predation) may facilitate aggregation, however, according to our results, it is neither necessary nor sufficient for aggregative multicellularity to be maintained when there is effective group-selection. Author summary: There is a lot of debate about how and why multicellularity emerged many times independently and what factors contributed to its prevalence. There are many theories why it was advantageous to be multicellular. Factors with direct advantage for aggregation (like avoiding predation) are evident but there are factors with indirect advantages, like spatiality and temporal heterogeneity. The latter can ensure the survival of the cooperative trait through group selection, without kin recognition or selection towards larger size (predation). In our model we investigated this hypothesis. We modelled two types of cells in a temporally heterogenous, spatial environments. Cooperators can associate to form aggregates while cheaters cannot by themselves stick to others but can enjoy the benefits of the aggregate. In resource-rich environments, cooperators have a disadvantage due to slower growth, but only they can create propagules in resource-poor environments. Cheaters therefore need to piggyback propagule-forming cooperators to make it to the next rich habitat. We show that cooperators can survive due to group selection enabled by spatiality in altering environments, without any further mechanism needed. [ABSTRACT FROM AUTHOR]

Insecticidal Bacillus thuringiensis Berliner (Bt) toxins produced by transgenic cotton (Gossypium hirsutum L.) plants have become an essential component of cotton pest management. Bt toxins are the primary management tool in transgenic cotton for lepidopteran pests, the most important of which is the bollworm (Helicoverpa zea Boddie) (Lepidoptera: Noctuidae) in the United States (U.S.). However, bollworm larvae that survive after consuming Bt toxins may experience sublethal effects, which could alter interactions with other organisms, such as natural enemies. Experiments were conducted to evaluate how sublethal effects of a commercial Bt product (Dipel) incorporated into artificial diet and from Bt cotton flowers impact predation from the convergent lady beetle (Hippodamia convergens Guérin-Méneville) (Coleoptera: Coccinellidae), common in cotton fields of the mid-southern U.S. Sublethal effects were detected through reduced weight and slower development in bollworm larvae which fed on Dipel incorporated into artificial diet, Bollgard II, and Bollgard 3 cotton flowers. Sublethal effects from proteins incorporated into artificial diet were found to significantly alter predation from third instar lady beetle larvae. Predation of bollworm larvae also increased significantly after feeding for three days on a diet incorporated with Bt proteins. These results suggest that the changes in larval weight and development induced by Bt can be used to help predict consumption of bollworm larvae by the convergent lady beetle. These findings are essential to understanding the potential level of biological control in Bt cotton where lepidopteran larvae experience sublethal effects. [ABSTRACT FROM AUTHOR]

Fire shapes animal communities by altering resource availability and species interactions, including between predators and prey. In Australia, there is particular concern that two highly damaging invasive predators, the feral cat (Felis catus) and European red fox (Vulpes vulpes), increase their activity in recently burnt areas and exert greater predation pressure on the native prey due to their increased exposure. We tested how prescribed fire occurrence and extent, along with fire history, vegetation, topography, and distance to anthropogenic features (towns and farms), affected the activity (detection frequency) of cats, foxes, and the native mammal community in south‐eastern Australia. We used camera traps to quantify mammal activity before and after a prescribed burn and statistically tested how the fire interacted with these habitat variables to affect mammal activity. We found little evidence that the prescribed fire influenced the activity of cats and foxes and no evidence of an effect on kangaroo or small mammal (<800 g) activity. Medium‐sized mammals (800–2000 g) were negatively associated with prescribed fire extent, suggesting that prescribed fire has a negative impact on these species in the short term. The lack of a clear activity increase from cats and foxes is likely a positive outcome from a fire management perspective. However, we highlight that their response is likely dependent upon factors like fire size, severity, and prey availability. Future experiments should incorporate GPS‐trackers to record fine‐scale movements of cats and foxes in temperate ecosystems immediately before and after prescribed fire to best inform management within protected areas. [ABSTRACT FROM AUTHOR]

Habitat is fundamental for facilitating various life activities in animals, for instance, snakes procure essential energy for survival and reproduction by selecting ambush microhabitats. While there has been extensive research on the selection of microhabitat for feeding in terrestrial and aquatic snakes, little is known about arboreal snakes. In the present study, we analyzed the ambush microhabitat preferences of Viridovipera stejnegeri, a widely distributed Asian pitviper in China, conducted association analysis between snake microhabitat and prey microhabitat and abundance to determine the ro5le of microhabitat selection in feeding. Employing random forest analysis and habitat selection functions, we further constructed a predictive framework for assessing the probability of ambush site selection by V. stejnegeri. Our results revealed that V. stejnegeri exhibited a distinct microhabitat preference for ambush prey. Among the 13 environmental factors assessed, V. stejnegeri showed pronounced preferences towards 12 of these factors, including climatic factors, geographical factors, and vegetation factors. Furthermore, although the preferences of V. stejnegeri overlapped substantially with those of its prey across multiple habitat factors, food abundance shows no significant association with various habitat factors of V. stejnegeri, and does not have significant predictive effect on habitat selection of V. stejnegeri. Therefore, we infer that V. stejnegeri does not preferentially select microhabitats with the highest food abundance, which does not support the hypothesis that "snakes select habitats based on the spatial distribution of prey abundance." By analyzing the characteristics of vegetation, geography, and climate, we conclude that V. stejnegeri tends to choose microhabitats with better ambush conditions to increase attack success rate, thereby achieving the optimal feeding success rate at the microhabitat scale, which is in line with the predictions of optimal foraging theory. This study provides new insights into the predation ecology and habitat selection of snakes. [ABSTRACT FROM AUTHOR]

In predator–prey interactions, the prey faces extreme challenges from predation, which drives the evolution of defense or anti‐predator mechanisms. Compared with adult birds, nestlings are more vulnerable but not helpless. However, data on whether nestlings eavesdrop on the danger signals transmitted by other prey nestlings and the mechanisms of eavesdropping remain limited. In brood parasitism, common cuckoo (Cuculus canorus) nestlings, raised by host adults who are not closely related, offer an instructive system for studying the transmission and recognition of danger signals among nestlings of different species that share special relationships. We played back the distress calls of common cuckoo nestlings to nestlings of three sympatric host species (the oriental reed warbler Acrocephalus orientalis, which is a primary host of the common cuckoo, the reed parrotbill Paradoxornis heudei, an occasional host, and the vinous‐throated parrotbill Sinosuthora webbiana, which is not parasitized in the study area) to investigate whether the host nestlings reduced their begging behavior. We also quantified the degree of inhibition toward begging behavior for these nestlings. The results revealed that, in response to the distress calls, the three sympatric host species markedly suppressed their begging behavior. This response can likely be attributed to the innate response of host nestlings caused by the general characteristics of distress calls, rather than the acoustic similarity and phylogenetic relationship between host nestlings and cuckoo nestlings. Furthermore, we observed that upon hearing the distress calls of cuckoo nestlings, the oriental reed warbler nestlings exhibited the greatest reduction in the total number of calls compared to the other two host species, potentially owing to stronger predation and parasitic pressures. This study suggests that host nestlings can detect danger signals emitted by parasitic nestlings; however, further investigation is needed to determine whether they can respond to distress calls from unfamiliar nestlings in different regions. [ABSTRACT FROM AUTHOR]

Unitary and modular sessile organisms both dominate in marine benthic communities, commonly preyed upon by the same generalist predators. The differences between unitary and modular defensive strategies may underlie the ways generalist predators control community structure, but this has never been empirically examined. We hypothesize that the individual size of an omnivorous mesopredatory shrimp affects the relative vulnerability of unitary and modular prey and hence translates into community structure. In a short‐term laboratory microcosm experiment, we assessed the effect of the shrimp individual size on an epibiotic assemblage of red algae blades initially dominated by three species of modular bryozoans and a unitary serpulid tubeworm. We found that the individual size of a shrimp determines its effect on the prey community composition. Large shrimp stronger than small shrimp increased the proportion of unitary tubeworms among the epibionts surviving predation. While large shrimp reduced the proportions of all the three dominant bryozoan species, small shrimp, in contrast, mostly increased the proportion of a bryozoan species with the smallest modules and largest colonies. This bryozoan, like the tubeworms, demonstrated a higher survival rate with larger individual (colony) size. Yet, against large shrimp this bryozoan was outperformed by the largest tubeworms almost immune to predation. Partial predation by small shrimp modestly improved survival of the largest bryozoan colonies. Thus, relative vulnerability of unitary and modular prey is determined by the predator individual size. Our findings clarify the complex way the size structures of generalist consumers and their prey shape communities by affecting the species‐specific relative performance of modular and unitary organisms. The demography of a foundation species and the competitive hierarchy can have additional effects by altering the balance of predation and competition. [ABSTRACT FROM AUTHOR]

Simple Summary: The oriental fruit fly, Bactrocera dorsalis, negatively impacts global agriculture. One promising mitigation strategy is biological control, emphasizing a comprehensive understanding of predator influences: specifically, the effects of predation risk on B. dorsalis development and reproduction. Our study investigated the predation risk effects of the mantis Hierodula patellifera Serville on B. dorsalis. We found that exposure to this predator or its odor shortened developmental time and increased fecundity in female B. dorsalis. However, male development and the death weights for both sexes remained stable. Our findings extend the understanding of H. patellifera's predation risk effects on B. dorsalis' life history, shedding light on potential alterations in the fitness and population dynamics of B. dorsalis. Additionally, we identified the use of predator odor as a possible innovative method for controlling B. dorsalis. Predators are dependent on the capture of prey to meet their energetic and nutritive requirements, which brings the risk of predation to prey. The predation risk is divided into consumptive and non-consumptive effects. Non-consumptive effects may manifest through altered growth and ontogenetic trajectories in prey species, a dynamic modulated by olfactory or other sensory cues from predators. Bactrocera dorsalis Hendel represents a major invasive threat to global horticulture. While earlier research was primarily centered on the consumptive interactions between B. dorsalis and its natural enemies, the potential consequences of non-consumptive interactions on the development of B. dorsalis have been overlooked. In this study, we investigated the impact of predation risk effects, induced by both visual exposure to the predatory mantis Hierodula patellifera Serville and its associated odor, on the life history traits of B. dorsalis. Female B. dorsalis demonstrated a reduced developmental time in the presence of a caged predator (H. patellifera) or predator odors, but showed significantly increased fecundity. Conversely, males displayed no significant change in developmental time. Additionally, neither the female nor male body weight at death was significantly influenced by the predation risk from the caged predator or predator odors. This study investigated the effects of predation risk on the development and reproduction of B. dorsalis, emphasizing the potential importance of odor risk in biological and pest control. [ABSTRACT FROM AUTHOR]

Simple Summary: The present study explores the impact of alternative prey on predator–prey dynamics in two contexts, without and with intraguild predation (IGP). It was found that without IGP, G. punctipes displayed a generalized functional response regardless of the alternative prey. However, under IGP conditions, the predator's functional response shifted to Type II, but the alternative prey did affect this response and it turned to a generalized type. In both contexts, handling times increased and consumption of the focal prey decreased as the density of the alternative prey increased. The presence of parasitized whitefly nymphs notably affected predator–prey dynamics, probably due to changes in prey characteristics. In biological control, joint releases of predators and parasitoids are standard. However, intraguild predation (IGP) can occur when a predator attacks a parasitoid, potentially affecting pest control dynamics. In addition to the focal prey (FP), Trialeurodes vaporariorum, the intraguild predator (IG-predator) Geocoris punctipes can consume the parasitoid Eretmocerus eremicus (IG-prey). In this IGP context with multiple prey, an alternative prey (AP), like the aphid Myzus persicae, may influence interactions. Theory predicts that, in simple interactions, a predator's functional response (FR) to the FP changes with the presence of an AP. However, whether this holds in an IGP context is unknown. In this study, we empirically tested that prediction. Our results show that without IGP, G. punctipes exhibits a generalized FR with and without AP. Nevertheless, with IGP, the predator exhibited a Type II FR at low and high AP densities, increasing pressure on the FP and potentially favoring short-term biological control strategies. However, when 25 AP were offered, the predator's response shifted, underscoring the importance of monitoring AP densities to prevent potential disruptions in FP control. In both contexts, the increase in AP produced a handling time increase and a decrease in consumption rate. These results indicate that the theoretical prediction of the effect of AP on the FR is met only under specific conditions, and the complexity of multitrophic interactions must be considered. [ABSTRACT FROM AUTHOR]

Simple Summary: Orb-weaving spiders can learn to avoid eating unpalatable prey, but what happens when they encounter one that they have never seen before? In the United States, a spider from East Asia has become established (the "jorō spider") in recent years, and their webs are most prominent during the late-summer and fall, which is also when migrating monarch butterflies are in abundance. Since monarch butterflies are unpalatable (because of developing on toxic milkweeds), we wondered if jorō spiders would recognize this and avoid eating them, given that these species do not coexist in East Asia. Using field observations of butterflies deposited into jorō spider webs, we found that these spiders do avoid eating monarchs, and even remove them from their webs in some cases. They readily attack other butterflies, even those that are similarly colored to monarchs. This raises many questions about how they perceive the "distastefulness" of monarchs, even without tasting the butterflies first. An invasive spider from East Asia has established in the U.S. southeast (the "jorō spider," Trichonephila clavata) and is rapidly expanding its range. Studies assessing the impact of this species are needed, including how expansive its diet is. An open question is whether monarch butterflies, Danaus plexippus, are a potential prey item for this spider, given that jorō spiders do not coexist with monarchs in their native range. Since monarch larvae feed on milkweed, they sequester cardiac glycosides into their adult tissues, rendering them unpalatable to many predators. At sites within northeast Georgia, we staged a series of trials (n = 61) where we tossed monarchs into jorō spider webs and, for comparison, performed similar trials with another aposematic species, gulf fritillary (Agraulis vanilla), and a palatable species, tiger swallowtail (Papilio glaucus). We recorded the outcome of the trials, which included whether the spider attacked or did not attack the prey. We also conducted a visual survey during the same fall season to look for evidence of jorō spiders consuming monarchs naturally. Our findings revealed that jorō spiders avoided eating monarchs; spiders only attacked monarchs 20% of the time, which was significantly less than the attack rates of similarly sized or larger butterflies: 86% for gulf fritillaries and 58% for tiger swallowtails. Some jorō spiders even removed monarchs from their webs. From our visual surveys of the surrounding area, we found no evidence of natural monarch consumption and, in general, butterflies made up only a fraction of the jorō spider diet. We conclude that jorō spiders appear to recognize monarch butterflies as being unpalatable, even without having a prior history with the species. This invokes questions about how these spiders can immediately recognize their unpalatability without touching the butterflies. [ABSTRACT FROM AUTHOR]

In this paper, we carry out some research on a predator–prey system with maturation delay, a stage structure for generalist predators and a Holling type-II functional response, which has already been proposed. First, for the delayed model, we obtain the conditions for the occurrence of stability switches of the positive equilibrium and possible Hopf bifurcation values owing to the growth of the value of the delay by applying the geometric criterion. It should be pointed out that when we suppose that the characteristic equation has a pair of imaginary roots λ = ± i ω (ω > 0) , we just need to consider i ω (ω > 0) due to the symmetry, which alleviates the computation requirements. Next, we investigate the nature of Hopf bifurcation. Finally, we conduct numerical simulations to verify the correctness of our findings. [ABSTRACT FROM AUTHOR]

Ladybird beetles Scymnus nubilus Mulsant, Scymnus interruptus (Goeze), and Hippodamia convergens Guérin-Méneville are key contributors to biological control of some pests including Phenacoccus solenopsis Tinsley. This study explores their feeding preferences, functional response, and interference in controlled laboratory conditions. Feeding experiments, including both no-choice and free-choice tests, were conducted at temperatures ranging from 15 to 35°C fed on different developmental stages of P. solenopsis. The study analyzed the functional response with Holling's disc equation and assessed mutual interference among predators using the Hassell and Varley model. In the no-choice feeding tests, H. convergens adults exhibited the highest consumption at 26°C, with values of 46.0 1st instar nymphs, 40.9 2nd instar nymphs, and 34.9 adult females of P. solenopsis, followed by S. interruptus. Free-choice feeding tests also showed a preference for 26°C, with H. convergens consistently consuming the most prey at all stages, followed by S. interruptus. Functional response analysis revealed a type II functional response for three predators. Hippodamia convergens exhibited a significantly higher attack rate (1.0250 h−1) and a shorter handling time (0.0449 h) compared to the other species. Interference among predators was observed, with a progressive decline in prey consumption as predator density increased. Mutual interference constants (m) were calculated as 1.70, 1.74, and 1.77 for S. nubilus, S. interruptus, and H. convergens, respectively. As predator densities increased, searching efficiency declined. This suggest that H. convergens and S. interruptus adults at 26°C with a prey density of 40 can effectively contribute to sustainable P. solenopsis management. [ABSTRACT FROM AUTHOR]

In a food chain, the role of intake patterns of predators is very influential on the survival and extinction of the interacting species as well as the entire dynamics of the ecological system. In this study, we investigate the affluent and intricate dynamics of a simple three-species food chain model in a discrete-time framework by analyzing the parameter plane of the system with simultaneous changes of two crucial parameters, the predation rates of middle and top predators. From the theoretical viewpoint, we study the model by determining the fixed points' biological feasibility and local asymptotic stability criteria, and performing some analyses of local bifurcations, namely, transcritical, flip, and Neimark–Sacker bifurcations. Here, we initiate the numerical simulation by plotting the changes of the prey population density in terms of a vital parameter of the system, and we observe the switching among different dynamical behaviors of the system. We also draw some phase portraits and plot the time series solutions to show the diverse characteristics of the system dynamics. Further, we move one step ahead to explore the intricate dynamical scenarios appearing in the parameter plane by forming Lyapunov exponent and isoperiodic diagrams. In the parameter plane of the system, we see the emergence of innumerable Arnold tongues. All these Arnold tongues are organized along a particular direction, and the beautiful arrangement of these tongues forms several kinds of period-adding sequences. The study sheds more light on various types of multistability occurring in the model system. We see the coexistence of three periodic attractors in the parameter plane. In this study, the most striking observation is the coexistence of four periodic attractors, which occurs infrequently in ecological systems. We draw the basins of attraction for the tristable and tetrastable attractors, which are complex Wada basins. A system with Wada basin is very sensitive to initial conditions and more erratic in nature than a system with fractal basin. Also, we plot the density of all interacting species in terms of the predation rates of middle and top predators and observe the variation in the population densities of all species with the variability of these two key parameters. In the parameter plane created by the simultaneous changes of two parameters, the system exhibits a variety of intricate and subtle dynamics, which cannot be found by changing only a single parameter. [ABSTRACT FROM AUTHOR]