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Nomadic species can rely on unpredictable resources making them challenging to understand and, consequently, to conserve. Here, we present knowledge advancement for a nomadic predator, the Short‐eared Owl Asio flammeus, by tracking individuals from a wide latitudinal range inclusive of most breeding populations in western Europe (Iceland, Scotland and Spain). Tracked owls showed pronounced plasticity in both inter‐ and intra‐individual behaviour. Distances between sequential breeding areas of individual owls ranged from 41 to 4216 km, with similar low fidelity to areas used at other times of year. Owls spent most (> 60%) of their time occupying home‐ranges (including breeding) and least (< 10%) undertaking long‐distance movements. The propensity for long‐distance movements was least for the most geographically isolated population, Iceland. Annual survival rates of 47% were lower than expected for an owl of comparable body mass with mortality concentrated during long‐distance displacements and immediately after breeding. Extensive, nomadic travel to find areas where large broods might be reared may incur carry‐over costs that lower survival. Conservation planning and assessment for nomadic species and their habitats must acknowledge the uncertainties associated with nomadism at scales from local to international. [ABSTRACT FROM AUTHOR]

Microplastics threaten the health of numerous marine organisms at all trophic levels. Currently, the topic is well studied among large predators. However, knowledge of microplastics present in organisms at lower trophic levels is poorly understood. The aim of this study was to assess the presence of microplastics within lower trophic level forage fishes. Four locations were sampled, classified into two categories based on human population: urban and non-urban. Five species were sampled: Striped Mullet (Mugil cephalus), Scaled Sardine (Harengula jaguana), Redfin Needlefish (Strongylura notata), Pinfish (Lagodon rhomboides), and Irish Pompano (Diapterus auratus). Of the 248 fish sampled, 99.6% contained microplastics, with a total of 2,126 pieces found in gastrointestinal tracts and livers. No significant difference in microplastics concentration among forage fish species was found. However, location had a significant effect on the frequency of microplastics found within the fishes, with the urban location near Miami, Florida having a higher frequency of occurrence compared with the other three sampled locations. This was the first study to assess microplastics within the forage fishes of southeastern Florida and provides further evidence that microplastics are pervasive throughout multiple trophic levels. [ABSTRACT FROM AUTHOR]

Predatory fishes often have strong top-down effects on coastal marine ecosystems and are considered a priority for conservation and management. Predator activity can influence prey distribution, abundance, and foraging behaviors, and is likely to influence habitat by impacting ecological and environmental characteristics as well as presence of competitor species. There are knowledge gaps of the effects of functional diversity, non-consumptive predator association, and environmental effects on fish assemblages, particularly within the Greater Caribbean region. In this study, effects of apex marine predatory fishes on diversity and abundance of prey ichthyofaunal communities were examined in putative predation low-risk (north side = lagoon) and high-risk (south side = flat) areas around South Bimini Island, The Bahamas. Baited remote underwater video surveys (BRUVs, n = 100 sites) deployed in the two nearshore habitat types captured abundance and potential predator-prey interactions, which were compared to assess potential risk effects within low-risk and high-risk habitats. Results showed a difference in ichthyofaunal communities between the two habitats, with teleost abundance highest on the south side. Depth, temperature, salinity, and dissolved oxygen were significantly linked to biotic assemblages. There were no differences in flight (escape) behavior of prey from predator (sharks versus great barracuda), suggesting that predator avoidance was a minimal factor in ichthyofaunal community structures. In the rapidly developing Greater Caribbean region, knowledge of ichthyofaunal communities and predator-prey interactions in different coastal habitats can better inform management regarding ecological changes over time and between island locations. [ABSTRACT FROM AUTHOR]

Stranding events of marine mammals provide valuable opportunities to study their biology, health, and causes for mortality, such as interactions with predators. Here we document the stranding of a deceased adult spinner dolphin (Stenella longirostris) with a shark bite (possibly an injury) on Utila Island, Honduras. The findings may shed light on predator-prey dynamics and scavenging in the region. [ABSTRACT FROM AUTHOR]

This paper discusses the large deviations for stochastic predator–prey model driven by multiplicative Lévy noise. Using Galerkin approximation, we initially prove the existence and uniqueness of solution. Due to the equivalence between Laplace principle and large deviation principle under a Polish space, the method of weak convergence has been followed in order to establish our results for this coupled system of equations. [ABSTRACT FROM AUTHOR]

In this paper, we propose and analyze a prey–predator model with the functional response of Beddington–DeAngelis and the fear effect that have infection only in prey populations. We determine existence criteria of several equilibria, and the stability at different equilibria are presented. We exert pesticide control over prey and additional food control over predators, the optimal control is obtained by the Pontryagin maximum principle. We confirm that adding controls to the predator and prey yields better results. Further we enrich our analysis with the inclusion of the existence and uniqueness of the optimal control. Finally, some numerical results to illustrate our analysis are presented. [ABSTRACT FROM AUTHOR]

The caterpillar Anticarsia gemmatalis (Lepidoptera: Noctuidae) is a prevalent pest in soybean plantations, managed using both natural and synthetic chemical products. However, the emergence of resistance in some populations emphasizes the need to explore alternative insecticides. Flupyradifurone, a neurotoxic insecticide, has not been previously used for controlling A. gemmatalis. This study evaluated the potential of flupyradifurone in the management of A. gemmatalis. Initially, the toxicity and anti-feeding effects, as well as histopathological and cytotoxic impacts, of flupyradifurone on A. gemmatalis were evaluated. Subsequently, the indirect effects of flupyradifurone on the midgut and fat body of the predator Podisus nigrispinus (Hemiptera: Pentatomidae) were verified. The results indicate the susceptibility of caterpillars to flupyradifurone, with an LC50 of 5.10 g L−1. Furthermore, the insecticide adversely affects survival, induces an anti-feeding response, and inflicts damage on the midgut of the caterpillars. However, flupyradifurone also leads to side effects in the predator P. nigrispinus through indirect intoxication of the caterpillars, including midgut and fat body damage. While flupyradifurone demonstrates toxicity to A. gemmatalis, suggesting its potential for the chemical control of this pest, the indirect negative effects on the predator indicate the need for its controlled use in integrated pest management programs with the insecticide and the predator. [ABSTRACT FROM AUTHOR]

Externally laid eggs are often responsive to environmental cues; however, it is unclear how such plasticity evolves. In Trinidad, the killifish (Anablepsoides hartii) is found in communities with and without predators. Here, killifish inhabit shallower, ephemeral habitats in sites with predators. Such shifts may increase the exposure of eggs to air and lead to possible desiccation. We compared egg-hatching plasticity between communities by rearing eggs terrestrially on peat moss or in water. The timing of hatching did not differ between communities when eggs were reared in water. Eggs from sites with predators responded to terrestrial incubation by hatching significantly earlier compared with water-reared eggs. These responses were weaker in sites with no predators. Such divergent trends show that the presence of predators is associated with evolutionary shifts in hatching plasticity. Our results provide evidence for local adaptation in embryonic plasticity at the population scale. [ABSTRACT FROM AUTHOR]

The spatial arrangement of organisms is significantly influenced by the structure of vegetation. Bromeliads, characterized by a remarkable architectural design featuring rosette‐like leaf arrangements for rainwater storage, act as habitats for various organisms. These organisms use bromeliads for shelter, foraging, reproduction and the supply of nutrients and moisture. This study investigated how specific aspects of bromeliad structure, such as the number, width and length of leaves, impact the behaviour and distribution patterns of the bromelicolous scorpion Tityus neglectus. In the examination of 110 sampled bromeliads, 33 scorpions were recorded, resulting in an occupancy rate of 30%. The likelihood of scorpion occurrence was associated with the plant's structure. The length and coefficient of variation in the width of leaves appeared as the main predictors, positively influencing scorpion presence while the number of leaves exhibited a negative relation with scorpion occurrence. The distribution of scorpions was uniform across the spatial design of bromeliads. Furthermore, T. neglectus demonstrated the ability to utilize water accumulated in the bromeliad to evade potential predators, submerging itself for, on mean, almost 8 min. We concluded that bromeliad structure is essential in shaping the distribution patterns and anti‐predatory behaviour of T. neglectus. [ABSTRACT FROM AUTHOR]

Despite global declines in the abundance and distribution of predators, conservation and reintroduction efforts are increasingly leading to predator recoveries. Unexpected species interactions and ecological consequences often arise when these predator recoveries occur. Here, we describe a novel species interaction in which coyotes (Canis latrans) kleptoparasitize North American river otters (Lontra canadensis) in a region of river otter recovery along the north‐central California coast, USA. We describe eight observations of coyotes scavenging otter‐killed waterbird carrion, including one observation in which river otters aggressively defended their prey from a coyote kleptoparasite. These observations highlight the importance of carrion provisioning as an overlooked pathway through which river otters facilitate nutrient subsidies to terrestrial scavengers. This behavior may have ecological implications including effects on the abundance, behavior, and health of scavengers as well as their interspecific interactions. We propose hypotheses and questions regarding these ecological consequences to guide further investigations into the cross‐ecosystem impacts of recovering river otter populations. [ABSTRACT FROM AUTHOR]

Predators and prey benefit from detecting sensory cues of each other's presence. As they move through their environment, terrestrial animals accumulate electrostatic charge. Because electric charges exert forces at a distance, a prey animal could conceivably sense electrical forces to detect an approaching predator. Here, we report such a case of a terrestrial animal detecting its predators by electroreception. We show that predatory wasps are charged, thus emit electric fields, and that caterpillars respond to such fields with defensive behaviors. Furthermore, the mechanosensory setae of caterpillars are deflected by these electrostatic forces and are tuned to the wingbeat frequency of their insect predators. This ability unveils a dimension of the sensory interactions between prey and predators and is likely widespread among terrestrial animals. [ABSTRACT FROM AUTHOR]

Optimal foraging and individual specialization theories suggest that different properties of the interactions between prey and predators determine foraging strategies. However, none of these theories consider how the nutritional status of the predators and the risk of being attacked by other predators may affect prey foraging strategy. Shelter-building spiders, such as Metazygia laticeps (Araneidae), build webs as dynamic traps to capture prey and may optimize capture efficiency while adopting strategies to minimize their exposure to predators by building a shelter and staying inside it most of the time. Prey capture, however, involves leaving the shelter, which may contribute to an increased risk of predation. Individuals may be more likely to take risks when they are in poor nutritional status. In this study, we conducted field experiments to assess support for the hypotheses that M. laticeps spiders with poor nutritional status (i) expose themselves to greater risk of predation during foraging and (ii) invest more silk in different web structures to increase prey capture success. Nutritional state was unrelated to exposure to predation and did not restrict web investment in M. laticeps. However, spiders left the shelter more quickly at night than during the day, regardless of their nutritional state. We suggest that individual's nutritional state does not determine foraging, and predation risk can affect general activity of spiders depending on foraging period. [ABSTRACT FROM AUTHOR]

We explored the potential of differences in foraging preferences to contribute to long-term species coexistence in aquatic predatory hemipterans. We hypothesized that predatory hemipterans would have distinct foraging preferences informed by their morphology. We used a prey choice experiment to test whether Belostoma flumineum, Pelocoris biimpressus, and Ranatra australis differed in their relative preferences of amphipod, damselfly naiad, and physid snail prey. We discovered that the predators showed complementarity in their foraging preferences with B. flumineum preferring snails, P. biimpressus damselfly naiads and R. australis amphipods as prey. Our results suggest that the disparate foraging preferences of aquatic hemipterans may facilitate their coexistence in aquatic systems but caution that studies need to explore whether patterns uncovered in the laboratory experiment reflect interactions in nature. [ABSTRACT FROM AUTHOR]

Simple Summary: The round goby is considered one of the most widespread Ponto-Caspian invasive species, which poses a threat to ecosystems and food web alterations. While it is known for direct predation, its interactions with native higher predators and its feeding behaviour upon their presence remain unclear. Therefore, we investigated how the exposure to chemical alarm cues emitted by conspecifics and the odour of a native predator, the European eel, affects the round goby's feeding activity. Surprisingly, the gobies did not exhibit any pronounced threat sensitivity to both types of chemical stimuli, which was observed in unchanged food consumption probability and gut evacuation rates. The obtained outcomes suggest boldness, great efficiency in food processing, and a potential competitive advantage over native counterparts when colonising new ecosystems, irrespective of local higher predator presence. The round goby Neogobius melanostomus is a notoriously invasive fish originating from the Ponto-Caspian region that in recent decades has successfully spread across the globe. One of its primary impacts is direct predation; in addition, when entering new ecosystems, the round goby is likely to become a food resource for many higher native predators. However, little is known either about the indirect effects of predators on the round goby as prey or its feeding behaviour and activity. The non-consumptive effect of the presence of higher native predators presumably plays an important role in mitigating the impact of non-native round gobies as mesopredators on benthic invertebrate communities, especially when both higher- and mesopredators occupy the same habitat. We tested the food consumption probability and gut evacuation rates in round gobies in response to chemical signals from a higher predator, the European eel Anguilla anguilla. Gobies were placed individually in experimental arenas equipped with shelters and exposed to water from a tank in which (a) the higher predator had actively preyed on a heterospecific prey, earthworms Lumbricus sp. (the heterospecific treatment; HS); (b) the higher predator had fed on round gobies (the conspecific treatment; CS); or (c) the water was provided as a control treatment (C). To ensure exposure to the chemical stimuli, this study incorporated the application of skin extracts containing damaged-released alarm cues from the CS treatment; distilled water was used for the remaining treatments. No significant differences were observed in either the food consumption probability or gut evacuation rate in the tested treatments. Despite the lack of reaction to the chemical stimuli, round gobies did exhibit high evacuation rates (R = 0.2323 ± 0.011 h−1; mean ± SE) in which complete gut clearance occurred within 16 h regardless of the applied treatment. This rapid food processing suggests high efficiency and great pressure on resources regardless of the presence or not of a higher predator. These findings hint at the boldness of round gobies, which did not exhibit any pronounced threat sensitivity. This would seem to suggest great efficiency in food processing and a potential competitive advantage over local native species when colonising new ecosystems, irrespective of the presence of native predators. Our study did not detect any non-consumptive effect attributable to the higher predator, given that the feeding activity of the invasive round goby was not altered. [ABSTRACT FROM AUTHOR]

The freshwater snail Latia neritoides occurs in certain streams and lakes of New Zealand's North Island. It defends itself against predators with a unique mechanism - the release of sticky, glowing mucus. Two possible origins of this defence mucus had earlier been suggested: the foot and the pneumostome area. After examining the glandular system of the foot in a previous study, in the present study we examined the general morphology of L. neritoides, focusing on the mantle cavity. With the first complete 3D model of L. neritoides now available, it is possible to evaluate previous morphological studies and to give non-specialists a better understanding of the soft part anatomy of this fascinating gastropod. As a by-product of this, we also compared the capabilities of μ-CT and HREM on a methodological level. We characterized the two most common gland types in the mantel cavity (Lmcg1/Lmcg2) on the basis of their ultrastructure. They are present in large numbers and, therefore, regarded as likely candidates for being the producers of one or more components of the defence mucus. This notion was confirmed by histochemical analyses of Lmcg1 and Lmcg2 and other gland types in L. neritoides. [ABSTRACT FROM AUTHOR]

In this study, we investigated faecal specimens from legally hunted and road‐killed red foxes, raccoons, raccoon dogs, badgers and martens in Germany for parasites and selected zoonotic bacteria. We found that Baylisascaris procyonis, a zoonotic parasite of raccoons, had spread to northeastern Germany, an area previously presumed to be free of this parasite. We detected various pathogenic bacterial species from the genera Listeria, Clostridium (including baratii), Yersinia and Salmonella, which were analysed using whole‐genome sequencing. One isolate of Yersinia enterocolitica contained a virulence plasmid. The Salmonella Cholerasuis isolate encoded an aminoglycoside resistance gene and a parC point mutation, conferring resistance to ciprofloxacin. We also found tetracycline resistance genes in Paeniclostridium sordellii and Clostridium baratii. Phylogenetic analyses revealed that the isolates were polyclonal, indicating the absence of specific wildlife‐adapted clones. Predators, which scavenge from various sources including human settlements, acquire and spread zoonotic pathogens. Therefore, their role should not be overlooked in the One Health context. [ABSTRACT FROM AUTHOR]

Implementing effective, affordable and ethical conservation management will be crucial for minimising future biodiversity losses. Such management requires reliable foundational evidence to help managers make informed choices about how to address the needs of their target species. Unfortunately, such evidence is still lacking for many species and management scenarios.One major global challenge is improving the reproductive success of threatened species in the context of predation. We conducted a systematic review and meta‐analysis of in situ experiments that used non‐lethal methods to protect bird nests against predators, with the aims of summarising global trends in nest protection efforts, comparing the effectiveness of different protection measures and informing future research and management. We considered peer‐reviewed studies in English.We detected a large geographic and taxonomic bias in the evidence base with 58% of articles conducted in North America and 76% on ground‐nesting birds. Less than 3% of articles involved taxa listed as Endangered or Critically Endangered and 51% of study units lasted just a single breeding season.Nests protected with exclosures, fences and guards were more likely to be successful than their unprotected controls. Interventions involving deterrents, conditioned taste aversion, chemical camouflage and diversionary feeding did not have a significant positive effect on nest success, but the interventions in these categories were less common and more diverse in nature.Synthesis and applications. To increase their conservation value, future non‐lethal nest protection experiments should whenever possible clearly state overall aims, take place over multiple seasons, use a comparable control and test non‐lethal protection methods independently of lethal predator control. Greater focus is required on under‐studied taxa such as cup‐nesting songbirds and birds in South America, Africa and Asia, and novel protection techniques such as deterrents and chemical camouflage. Practitioners should consider the evidence we synthesise here when deciding whether non‐lethal nest protection approaches are optimal for their study system, to increase conservation success and reduce ethical and financial costs. [ABSTRACT FROM AUTHOR]

Camouflage and warning signals are different antipredator strategies, which offer an excellent opportunity to study the evolutionary forces acting on prey appearance. Edible prey often escape detection via camouflage, which usually leads to apostatic selection favoring rare morphs. By contrast, defended prey often display conspicuous coloration acting as warning signals to predators, which usually leads to positive frequency dependence and signal uniformity. However, when two morphs of the same species vary greatly in conspicuousness, the maintenance of both cryptic and conspicuous forms in profitable prey populations remains enigmatic. Using the white and melanic morphs of the invasive box tree moth (Cydalima perspectalis) presented at three different frequencies, we investigate (a) the palatability of caterpillars and adult moths to birds, (b) predation rates on the less conspicuous melanic morph, and (c) the role of frequency dependence in balancing morph frequencies. Our results show that caterpillars are distasteful for birds but not adult moths that are fully palatable. We found that the less conspicuous, melanic morph, benefits from reduced predation due to its lower detectability. The more conspicuous, white morph, instead, is more predated and is best off when common, suggesting positive frequency dependence. These results offer new insights into the evolution of color polymorphism and prey defenses in a polymorphic moth species. Further investigation is required to understand the role of different predation regimes on the maintenance of the polymorphism in this species and test whether additional selection pressures operate in natural populations. [ABSTRACT FROM AUTHOR]

Brachycaudus divaricatae Shaposhnikov has spread in many European countries over the last decades, where it causes intensive damage to Prunus cerasifera. Forty P. cerasifera trees were monitored in 2013 at Dārziņi, on the outskirts of Riga city (Latvia), to obtain data on seasonal dynamics of an exotic aphid species, B. divaricatae. Brachycaudus divaricatae was predominant on its only known host plant species, P. cerasifera. Other aphid species were found on monitored trees: Brachycaudus sp., Hyalopterus pruni (Geoffroy) and Rhopalosiphum nymphaeae (L.). The target species, B. divaricatae was the most abundant, followed by H. pruni, but only B. divaricatae reached the highest infestation level. The latest date of registered B. divaricatae colonies was 31 October 2013. Many predatory arthropods belonging to Acari, Araneae, Coleoptera, Diptera, Hymenoptera, and Neuroptera were registered in B. divaricatae colonies. The most abundant predators were dipteran larvae from the families Cecidomyiidae and Syrphidae. Predatory dipterans most abundant were only at the beginning of the season (June). Later in the season, the number of spiders increased in aphid colonies, and of 365 spiders, 43.8% were members of the Linyphiidae family. Five ant species were caught in B. divaricatae colonies, and Formica cinerea Mayr was the most abundant. [ABSTRACT FROM AUTHOR]

The harlequin ladybird (Harmonia axyridis) shows a high level of colour polymorphism. Particular forms differ in their colour combination, pattern and abundance.Two species of wild‐caught passerines native to Central Europe were offered various forms of ladybirds, differing in their colour pattern and abundance in nature. We predicted that those forms that are more abundant in the wild are better protected, as they are more familiar to predators.Forms novemdecimsignata and spectabilis, which represent 97% of individuals in the wild population, significantly differ in their visual appearance (mostly orange vs. mostly black). The form axyridis is very rare in the wild, and suturalis and aninkae do not occur in the wild and were derived from laboratory breedingsAs predators, we used great tits (Parus major), which are very aversive towards ladybirds, and tree sparrows (Passer montanus), which are quite willing to attack and even eat ladybirds.We compared bird responses to particular ladybird colour forms and included a brown‐painted control to test the effect of conspicuous colours.We showed that both species of birds attacked all conspicuous forms of the ladybird equally and usually very rarely. The brown‐painted novemdecimsignata form was attacked more frequently compared with the conspicuous forms, showing that the visual appearance prevents birds from attacking any conspicuous colour combination. Sparrows tended to eat the attacked ladybirds of forms novemdecimsignata, spectabilis and brown painted. The rare axyridis form and laboratory forms were very well protected from the attack, very likely due to neophobia.We may conclude that despite the outstanding polymorphism of H. axyridis, its protection against avian predators is very effective as long as the red‐and‐black pattern is preserved. [ABSTRACT FROM AUTHOR]

Augmentative release of predators is used in agriculture to suppress pest populations and minimise crop damage. However, predators affect prey populations not only through consumption but by inducing changes to prey morphology, physiology, behaviour and life history. These risk‐induced trait responses can increase prey fitness, potentially reducing the efficacy of certain predators as biocontrol agents.We investigated how non‐consumptive effects contribute to the overall influence of predators by modelling the effect of the predator Podisus maculiventris on the population dynamics of a major agricultural pest, the Colorado potato beetle (Leptinotarsa decemlineata). We developed a demographic model incorporating both consumption and non‐consumptive Podisus‐induced shifts in beetle reproductive strategy. Our model combines data from multiple mechanistic experiments showing that predator‐exposed beetles produce fewer offspring but increase offspring provisioning, and that provisioned larvae have increased survival when predators are present. We simulated beetle densities across multiple beetle generations and a range of predator densities.The influence of non‐consumptive effects depended on predator density. At low predator densities, non‐consumptive effects strengthened the negative effect of predators by up to 45%, and risk‐induced changes to offspring provisioning had a stronger effect on prey densities than reduced offspring quantity. In contrast, at high predator densities, non‐consumptive effects changed the effect of predators by <5%, likely because beetle densities were very low both with and without non‐consumptive effects.Our results suggest that even adaptive responses to predation risk by prey do not necessarily reduce the ability of predators to suppress pest populations. [ABSTRACT FROM AUTHOR]

We formulate and analyze a general diffusive predator–prey system with predator maturation delay. Global asymptotic stability of the predator-free equilibrium and uniform persistence results are obtained under different conditions on model parameters. We then use Leray–Schauder degree theory to establish the existence of the spatial heterogeneous steady state. Moreover, we prove the global existence of nonconstant positive steady states bifurcated from the positive constant steady state. Taking the time delay as the bifurcation parameter, we conduct local and global Hopf bifurcation analysis and prove the boundedness of global Hopf branches. Rigorous analyses for global Hopf bifurcation and branches are challenging but important in understanding global transitions of dynamics. [ABSTRACT FROM AUTHOR]

Many predators ambush prey rather than pursue them or shift between foraging modes. Active predators typically encounter prey more frequently than ambush predators. I designed a simulation model to examine whether this always holds and how active and ambush predators fare in capturing mobile prey. Prey foraged for clumped resources using area‐restricted search, shifting from directional movement before resource encounter to less directional movement afterward. While active predators succeeded more than ambush predators, the advantage of active predators diminished when ambush predators were positioned inside resource patches rather than outside. I investigated the impact of eight treatments and their interactions. For example, regeneration of prey resources increased the difference between ambush predators inside and outside patches, and uncertain prey capture by predators decreased this difference. Several interactions resulted in outcomes different from each factor in isolation. For instance, reducing the directionality level of active predators impacted moderately when applied alone, but when combined with resource regeneration it led to the worst success of active predators against ambush predators inside patches. Ambush predators may not always be inferior to active predators, and one should consider the key traits of the studied system to predict the relative success of these two foraging modes. [ABSTRACT FROM AUTHOR]

In this study, we proposed a Leslie-Gower prey-predator model, whose dynamics includes a constant effort harvesting rate in predators and an additive Allee impact on prey. A system of stochastic differential equations is also used to study its behaviour, with the assumption that each population's exposure to environmental unpredictability is represented by noise terms. This kind of randomness is considerably more reasonable and realistic in the proposed paradigm. Due to the paucity of studies on the dynamics of this kind of model, this investigation is being believed to be a way to advance the subject of literature. First, we establish the system's positivity and boundlessness. Next, we look into the dynamics of every one of the stable states, the form of the positive equilibrium point, and the continued existence of every species in the system.It is established that the equilibrium levels of prey and predator are impacted by the Allee effect parameter as well as the impact of harvesting. The positive steady state point's global stability criterion is derived. By selecting the Allee effect and harvesting effort as the bifurcation parameters, it has been established that a Hopf bifurcation exists close to the interior steady state. This study is novel since it incorporates various ecological factors into a single model, potentially opening up new perspectives on predator-prey relationships. To support the mathematical conclusions, rigorous numerical visualisations of the key parameters are provided below using specific hypothetical data. In conclusion, we may state that our model is a project that aims to preserve the ecological equilibrium of the natural world. [ABSTRACT FROM AUTHOR]

Predation and competition are two major factors that drive natural selection. When they vary unpredictably, selection has promoted the evolution of plastic responses in behavioral, morphological and life-history traits. These responses are not independent of each other and often represent a trade-off between conflicting interests. We conducted a common-garden experiment to study the effects of predation and competition on the morphology and life history of R. dalmatina and R. latastei tadpoles. The experiment used a randomized-block design, where tadpoles were raised either with or without siblings and either with or without predators. Regardless of the treatments, R. dalmatina grew faster, developed proportionally larger tails, proportionally smaller bodies, and completed metamorphosis earlier than R. latastei. Both species developed relatively larger bodies with competitors, and relatively larger tails with predators. While the relative increase in body size with competitors was similar in the two species, the increase in tail size with predators was greater in R. dalmatina, suggesting that this species invested more in defense than R latastei. Competitors delayed metamorphosis in both species and in R. latastei they negatively affected froglet body size and shape. Conversely, predators delayed the metamorphosis only in R. dalmatina. This delay was the long-term cost paid by R. dalmatina for the short-term benefits of developing more effective behavioral and morphological defensive traits. Significance statement: Tadpoles develop plastic morphological and life-history traits in responses to predators and competitors. This plasticity is costly in terms of both performance and function. Our study shows that two closely related brown frogs have evolved different trade-offs in their plastic responses to predators and competitors. Rana dalmatina, which grew and developed faster than R. latastei, was more sensitive to predators and developed more effective morphological defenses. Both species delayed metamorphosis at high density, but R. dalmatina did it more than R. latastei. Predators did not affect the duration of larval development in R. latastei, whereas in R. dalmatina, they further delayed metamorphosis. This delay was the long-term cost of the R. dalmatina's larger investment in short-term defensive traits. [ABSTRACT FROM AUTHOR]

The feeding behavior and trophic niche overlap between Stone Marten (Martes foina Erxleben, 1777) and Red Fox (Vulpes vulpes Linnaeus, 1758) in two regions of Bulgaria with different human influence were determined. A total of 1,440 fecal samples were collected from agricultural area in the Upper Thracian Plain and from near-natural habitat in Central Stara Planina Mts. In agricultural area, both predators preferred fruits in all seasons, while rodents dominated in winter diets in the mountain area. Our results showed that the Stone Marten and the Red Fox had high trophic niche overlap in both habitats. [ABSTRACT FROM AUTHOR]

Many insects rely heavily on visual cues in foraging and other life activities. Mantids are insect predators that usually ambush prey. The sophisticated visual system of mantids allows them to spot, track, and strike at prey with high accuracy. Mantids are categorized as diurnal animals in most cases, while our field observations suggested that they were active in foraging both day and night. Therefore, we hypothesize that predation in dim light is possible for mantids, while mantids are unable to capture prey in complete darkness. In this study, we experimentally examined whether different light conditions could affect the predation success and efficiency of mantid nymphs and adults, Hierodula chinensis Werner (Mantodea: Mantidae), through behavioral observations. Individual mantids were placed in individual chambers in complete darkness, simulated moonlight (0.1 lux), or simulated dusk (50 lux) conditions and were allowed to forage for prey items for 10 min. Our observations showed no evidence that H. chinensis could capture any prey in complete deprivation of light. The proportion of nymphs with successful predation in simulated moonlight was 50% higher than that in complete darkness and 45.83% lower than that in simulated dusk. The proportion of adults with successful predation in simulated moonlight was 42.11% higher than that in complete darkness and 57.89% lower than that in simulated dusk. Overall, the results provide new insights into the behavioral ecology of diurnal predators at night, with potential association with moonlight, starlight, and light pollution. [ABSTRACT FROM AUTHOR]

Chemical eavesdropping is a critical tool used by organisms to gain information about their environment and mediate interactions with other organisms within it, such as prey gaining information about predators and vice versa. However, most chemical eavesdropping studies focus on information used by prey species, not predators. The goal of this study was to assess whether or not a desert ambush predator, Crotalus ornatus (Eastern Black-tailed Rattlesnake), differentiates among chemical cues from nonnative familiar and novel native prey items when choosing ambush spots. Naive neonate C. ornatus were obtained from wild mothers, born and raised in captivity, and placed in an arena where they were presented with aquatic extracts from the integument from 9 known and suspected prey items, a familiar non-native prey item, and a tap water control. Their reactions to the chemical extracts were recorded under diurnal and nocturnal conditions, and they were given a tongue-flick ambush (TFAM) score based on their predatory behavior towards the chemical cue. Ten naive neonate C. ornatus were put through each of the 11 trials under diurnal and nocturnal conditions, and based on TFAM scores, snakes differentiated among the chemical cues, but there were no detectable differences based on photoperiod. Post hoc pairwise tests revealed that snakes preferred native small mammal and lizard prey. The snakes used in this study had never been exposed to wild prey stimuli in their native ecosystem and had fed exclusively on non-native mammalian prey in captivity, thus their preference for native small mammals and lizards indicates an innate basis for prey preference in C. ornatus. [ABSTRACT FROM AUTHOR]

Predatory arthropods play a crucial role in mitigating the impact of insect pests. However, the use of broad-spectrum insecticides in pest management methods can pose a threat to predator populations. In response to the need for safer and more selective insecticides that spare natural enemies, an effort was made to know the diversity of predatory fauna and effect of seed dressers and foliar spraying insecticides on coccinellids and spiders at the Main Agricultural Research Station in Dharwad, Karnataka, during the summer 2021 and 2022. The treatments included four seed treatments, four seed treatments in combination with foliar spray, two foliar sprays alone, and an untreated control. Predator numbers were recorded at 45 and 65 days after sowing (DAS), selecting 20 plants randomly in all treatments. The results demonstrated that during the summer 2021 and 2022, seed treatment with chlorpyriphos 20EC was identified as safe, exhibiting the highest number of coccinellids (0.55 and 1.33 per plant) and spiders (0.54 and 1.62 per plant), respectively. These results were statistically comparable to other treatments like, seed treatment with imidacloprid 60 FS (0.49 and 1.00 coccinellids per plant) (0.48 and 1.38 spiders per plant), thiamethoxam 30 FS (0.45 and 0.95 coccinellids per plant) (0.44 and 1.22 spiders per plant) during 2021 and 2022 summer, respectively, ranking just below the untreated control. A significant difference in the population of coccinellids and spiders was observed among all the treatments, with seedtreated plants recording the highest predatory populations compared to foliarsprayed plants. Consequently, the study concludes that seed treatment chemicals prove to be safer for predators while still effectively providing necessary pest control. This highlights the potential of integrating such seed treatment methods into pest management strategies to enhance overall efficacy while minimizing adverse effects on beneficial predator populations. [ABSTRACT FROM AUTHOR]

Although lethal interactions between wolves and other apex carnivores have been reported for a handful of species, the killing or consumption of wolves by free-ranging golden eagles has rarely been reported. Here, we present four opportunistic field observations documenting the consumption of a wolf pup by free-ranging golden eagles and predatory behavior of eagles towards wolf pups. Although we could not confirm the killing and consumption of wolves by eagles in a single predatory event, actual predation seems plausible based on our observations. We hypothesize that these intraguild apex predators' interactions, consisting on a smaller raptor predator attacking or consuming a lager mammal and social predator, are rare events, but provide valuable information on potential relationships across keystone apex predators. [ABSTRACT FROM AUTHOR]

Some predators prefer to settle on leaf patches with microstructures (e.g., trichomes and domatia), leaving traces on the patches. Herbivorous arthropods, in turn, select leaf patches in response to these traces left by predators. It remains unclear whether traces of predators on leaf patches affect the distribution of herbivorous prey within plants through plant microstructure. Therefore, we examined the distribution of herbivorous mite (Tetranychus urticae) and predatory mite (Phytoseiulus persimilis) by investigating their oviposition pattern. We used a kidney bean plant (Phaseolus vulgaris) with two expanded primary leaves and the first trifoliate leaf, focusing on leaf trichomes as the microstructure. The density of trichomes was higher on the first trifoliate leaf than on the primary leaves and on the abaxial surface of the leaves than on the adaxial surface. Adult female P. persimilis laid more eggs on the first trifoliate leaf to the primary leaves. Although adult female T. urticae preferred to oviposit on the abaxial surface of primary leaves, previous exposure of plants to predators diminished this preference. The altered egg distribution would be a response to the traces of P. persimilis rather than eggs of P. persimilis. Our findings indicate that T. urticae reproduces on leaf patches with traces of predators without altering their oviposition preference. Given that the presence of predator traces is known to reduce the reproduction of T. urticae, it may have a substantial effect on the population of T. urticae in the next generations on kidney bean plants. [ABSTRACT FROM AUTHOR]

Background: Toumeyella parvicornis is an alien pest of recent introduction in Italy that infests stone pines (Pinus pinea L.), its main host plant in Europe. Infestations are currently controlled through endotherapic treatments, but the high costs and the long‐term inefficacy highlight the need for alternative control strategies applicable in natural systems as well. An analysis of the effectiveness of autochthonous and naturalized predators is the first step to achieve this goal. This work focused on two candidate predators, Exochomus quadripustulatus and Cryptolaemus montrouzieri (Coleoptera: Coccinellidae), that may potentially control T. parvicornis. The analysis was carried out under laboratory‐controlled and semi‐field conditions. Results: Laboratory tests were carried out to assess: (i) the predation rate of the ladybugs over different densities of pest preimaginal stages, and (ii) the effect of the presence of heterospecific and conspecific predators on the attractiveness of prey colonies. Semi‐field experimentations were carried out by wrapping infested stone pine twigs with net sleeves and applying one of three treatments: (i) Exochomus quadripustulatus, (ii) Cryptolaemus montrouzieri, and (iii) control containing only the pest population. Both the ladybugs were attracted by T. parvicornis, offered as prey. Exochomus quadripustulatus was more attracted to conspecific and heterospecific ladybugs than Cryptolaemus montrouzieri and responded to prey more quickly. Conclusions: The results obtained could be useful for planning further experimentations to explore the potential use of these predators in biological control programs that may be applied in infested areas. Besides the use in an urban context, where pesticide use is strongly limited, the release of natural enemies may help safeguard stone pine forests. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

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Predatory publishing poses significant challenges to academic integrity and progress. It requires the involvement of academic institutions, funding bodies, and policymakers to establish robust evaluation mechanisms and promote ethical publishing practices. This study examines the effectiveness of implementing promotion policies to discourage unethical academic publishing, focusing on Kwame Nkrumah University of Science and Technology (KNUST) in Ghana. This study analyses 273 promotion applications submitted from January 2022 to November 2023, regardless of approval. The results show that researchers at KNUST submit relatively more publications to recommended outlets after the implementation of the new promotion guidelines. Moreover, with nine out of ten non-verified publications found to be from predatory journals, the verification process effectively discourages publication such outlets. Our study therefore confirms that the verification process can identify predatory publication outlets. Consequently, it is recommended that research institutions eliminate incentives for publishing in questionable outlets through publication criteria as part of promotion standards. [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]

The behavioural responses of predator-naïve (laboratory-born), predator-experienced (laboratory-born but with short-term experience with predators), and wild-caught (with long-term experience with predators in natural settings) tadpoles of Sphaerotheca breviceps to carnivorous predatory tadpoles of Hoplobatrachus tigerinus was studied in the laboratory. The predator's stimulus solution (kairomones) was used to simulate predation threat. All S. breviceps tadpoles (i.e., predatornaïve, predator-experienced and wild-caught) exhibited behavioural antipredator responses, i.e., reduced swimming activity and time spent swimming, and had a higher burst speed in response to water-borne kairomonal cues of predators. Wildcaught tadpoles showed stronger responses than predator-naïve and predator-experienced tadpoles and the latter exhibited stronger responses than predator-naïve tadpoles. Our study thus suggests that antipredator behaviour in these tadpoles is basically innate. Furthermore, the enhanced antipredator behaviour of wild-caught tadpoles indicates that learning is involved. [ABSTRACT FROM AUTHOR]

Entomopathogenic fungi (EPF) are economical and environmentally friendly, forming an essential part of integrated pest management strategies. We screened six strains of Beauveria bassiana (B1-B6) (Hypocreales: Cordycipitaceae), of which B4 was the most virulent to Bactrocera dorsalis (Hendel) (Diptera: Tephritidae). We further assessed the biological characteristics of strain B4 and the environmental factors influencing its ability to infect B. dorsalis. We also evaluated the effects of B4 on two of the natural predators of B. dorsalis. We found that strain B4 was the most virulent to 3rd instar larvae, pupae, and adult B. dorsalis, causing mortality rates of 52.67, 61.33, and 90.67%, respectively. B4 was not toxic to B. dorsalis eggs. The optimum B4 effects on B. dorsalis were achieved at a relative humidity of 91-100% and a temperature of 25°C. Among the six insecticides commonly used for B. dorsalis control, 1.8% abamectin emulsifiable concentrate had the strongest inhibitory effect on B4 strain germination. B4 spraying affected both natural enemies (Amblyseius cucumeris and Anastatus japonicus), reducing the number of A. cucumeris and killing A. japonicus adults. We found a valuable strain of EPF (B4) that is virulent against many life stages of B. dorsalis and has great potential for the biological control of B. dorsalis. We also provide an important theoretical and practical base for developing a potential fungicide to control B. dorsalis. [ABSTRACT FROM AUTHOR]

The assessment of site suitability is a crucial step for informing future successful species reintroductions. It ensures that translocated species have the highest chance of survival in their new environment while minimising ecological risks. However, it can be challenging when risk factors are unknown, especially when working with sessile species that cannot easily relocate to more favourable conditions. Under these scenarios, rapid (1-2 week-long), small-scale (< 1 m²) experimental translocations can help reduce uncertainty and improve restoration outcomes. This study conducted small-scale experimental translocations of green-lipped mussels, Perna canaliculus, to 11 shallow coastal sites spread across Tık? apa Moana/the Hauraki Gulf, Aotearoa/New Zealand to investigate the relationship between predator abundance, environmental factors, and mussel loss to help refine existing site selection criteria. The total number of known mussel predators counted from timelapse images was used as a proxy for potential predator pressure. Translocated mussel survival ranged from 10 - 99% and was best predicted by current speed, wind direction, predator abundance, water clarity, and depth (adjusted R² = 0.505). Predator abundance was best explained by site location (p = 0.001) and had weak correlations among environmental parameters (Rho = 0.067). These results suggest that small, short-term (1-2 week) experimental translocations can help to refine site selection criteria and reduce uncertainty in the site-selection process for larger-scale shellfish reintroduction efforts with unknown and/or hard-tocontrol risk factors. [ABSTRACT FROM AUTHOR]

Among-individual variation in predator traits is ubiquitous in nature. However, variation among populations in this trait variation has been seldom considered in trophic dynamics. This has left unexplored (a) to what degree does among-individual variation in predator traits regulate prey populations and (b) to what degree do these effects vary spatially. We address these questions by examining how predator among-individual variation in functional traits shapes communities across habitats of varying structural complexity, in field conditions. We manipulated Chinese mantis (Tenodera sinensis) density (six or twelve individuals) and behavioral trait variability (activity level by movement on an open field) in experimental patches of old fields with varying habitat complexity (density of plant material). Then, we quantified their impacts on lower trophic levels, specifically prey (arthropods > 4 mm) and plant biomass. Predator behavioral variability only altered prey biomass in structurally complex plots, and this effect depended on mantis density. In the plots with the highest habitat complexity and mantis density, behaviorally variable groups decreased prey biomass by 40.3%. In complex plots with low mantis densities, low levels of behavioral variability decreased prey biomass by 32.2%. Behavioral variability and low habitat complexity also changed prey community composition, namely by increasing ant biomass by 881%. Our results demonstrate that among-individual trait variation can shape species-rich prey communities. Moreover, these effects depend on both predator density and habitat complexity. Incorporating this important facet of ecological diversity revealed normally unnoticed effects of functional traits on the structure and function of food webs. [ABSTRACT FROM AUTHOR]

Predators significantly impact the development process and subsequently influence the metamorphic decisions of amphibian larvae. Larvae often exhibit induced growth and metamorphic plasticity in response to the presence of predators. However, growth and development rates are not always perfectly correlated, growth responses can vary throughout ontogeny. It is crucial to consider the stage‐specific growth responses induced by predators. Here, we employ a critical windows experimental design and examine development‐related growth and metamorphic responses to predators in the endangered Chinhai spiny newt (Echinotriton chinhaiensis). Our findings reveal that predators constrain the development process of spiny newt larvae and also impact survival to metamorphosis. Inducible plasticity predominantly exhibits in the early and middle stages of larval development. Our results also suggest that diverse developmental plasticity has been adopted by larvae in response to predators. The presence of predators during early stage induces larvae to exhibit a same size at metamorphosis but a prolonged time to metamorphosis, while predators present during middle stage induce larvae to exhibit a large size at metamorphosis but a same time to metamorphosis. The presence of predators at the late developmental stage does not induce any plasticity in larval growth and metamorphosis. Moreover, these results also suggest that several stages of larval development are likely critical developmental windows for spiny newt larvae. This study not only provides basic biological information on predator‐induced developmental plasticity of the endangered Chinhai spiny newt but also likely provides biological insights for the implementation of in situ conservation and preservation efforts for endangered species. [ABSTRACT FROM AUTHOR]

In this paper, we study a predator--prey mite model of Leslie type with generalized Holling IV functional response. The model is shown to have very rich bifurcation dynamics, including subcritical and supercritical Hopf bifurcations, degenerate Hopf bifurcation, focustype and cusp-type degenerate Bogdanov--Takens bifurcations of codimension 3, originating from a nilpotent focus or cusp of codimension 3 that acts as the organizing center for the bifurcation set. Coexistence of multiple steady states, multiple limit cycles, and homoclinic cycles is also found. Interestingly, the coexistence of two limit cycles is guaranteed by investigating generalized Hopf bifurcation and degenerate homoclinic bifurcation, and we also find that two generalized Hopf bifurcation points are connected by a saddle-node bifurcation curve of limit cycles, which indicates the existence of global regime for two limit cycles. Our work extends some results in the literature. [ABSTRACT FROM AUTHOR]

Predators affect their prey through consumptive and non-consumptive effects (NCEs). Regarding marine NCEs, predator chemical cues (e.g., exudates) can trigger various anti-predator responses in prey that can vary in magnitude according to the intensity of the perceived cues. Specimens of the mussel Perumytilus purpuratus were exposed to seawater that held different densities of the predatory snail Acanthina monodon as a proxy for predator cue intensity. The response of mussels was quantified in terms of valve gape size (VGS), clearance rate (CR), and oxygen consumption rate (OCR). The results showed that mussels reduced VGS, CR, and OCR as a function of the intensity of the predator exudates to which they were exposed. These results suggest that mussels are not only able to detect predators through their chemical exudates but can also detect the intensity of the predatory signal and thus respond physiologically (CR, OCR) and behaviorally (VGS) in accordance to the potential predation risk. These responses may have cascading effects at the community level, given that mussels are foundation species. [ABSTRACT FROM AUTHOR]