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In this study, Crayfish Optimization Algorithm (COA) was examined. COA, which simulates crayfish's summer resort behavior, competition behavior, and foraging behavior. COA is a successful heuristic algorithm originally proposed for continuous optimization problems. In this study, the continuous search space of COA was converted into a binary search space with eight different S- and V-shaped transfer functions. Thus, the Binary COA (BinCOA) algorithm was proposed to the literature. The success of BinCOA variations was analyzed on 25 different knapsack problems of different sizes. The most successful transfer function was determined as BinCOAV1. Since the success of BinCOAV1 fell behind many binary heuristic algorithms in the literature, BinCOA was developed with two different methods (bitwise operator and repair method). Thus, the Improved BinCOA (IBinCOA_RX) algorithm was proposed in this study. BinCOA's local search ability and discovery ability in the binary search space have been improved. The resulting improved BinCOA variations (IBinCOAX (BinCOA with bitwise operator), IBinCOAR (BinCOA with repair method), and IBinCOA_RX (BinCOA with bitwise operator and repair method)) were analyzed in detail and the effect of each method added to BinCOA was detailed in the paper. The success of IBinCOA_RX has been proven by comparing it with eight different binary heuristic algorithms selected from the literature. According to the results, the IBinCOA_RX algorithm showed preferable success for binary optimization problems. In addition, in this study, the effectiveness of BinCOAV1 and IBinCOAX algorithms is also shown on a different binary problem, namely the uncapacitated facility layout problem (UFLP). [ABSTRACT FROM AUTHOR]

Due to the disproportionate role that large carnivores can have on communities and their global decline over the last century, carnivores are increasingly being repatriated across their historic ranges. The reintroduction of gray wolves (Canis lupus) can precipitate substantive changes to communities and ecosystems. Notably, wolves could have strong effects on smaller and subordinate carnivores, especially in altering their foraging behavior and prey selection. Past studies investigating wolf effects on other carnivores, however, have generally been conducted in relatively complex communities featuring a diverse assemblage of carnivores and prey and have lacked baseline (i.e. pre-repatriation) data. Consequently, researchers have quantified what a community looks like after wolf return, with little information on how the community behaved before. To better understand the effect of large carnivore repatriation on the foraging ecology of a carnivore community, we investigated the impact of reintroduced gray wolves on 2 meso-carnivores: Red Fox (Vulpes vulpes); and American Marten (Martes americana) within an insular and simple vertebrate community at Isle Royale National Park before and after wolf reintroduction. We analyzed >600 scats from 20 individual martens and 63 individual foxes as well as the stable isotopes of 9 and 22 tissue samples from martens and foxes, respectively, at both individual and population levels. We found that the wolf reintroduction had little effect on marten diet but strongly influenced fox diet depending on the analysis conducted. At the population level, our analysis revealed that both foxes and martens were dietary generalists consuming an array of food items including small prey, berries, and human food regardless of wolf presence. However, at the individual level, we found that prior to wolf repatriation foxes primarily consumed berries and small prey but following wolf repatriation the diet of foxes shifted to berries and human foods as well as large carrion. This post-wolf reintroduction shift in diet increased the dietary overlap between foxes and martens. Our work provides new insights into how the return of a large carnivore can alter the foraging ecology of small-bodied carnivores and act both to provision carrion resources as well drive other carnivores to consume more human food and increase dietary overlap. [ABSTRACT FROM AUTHOR]

The tropical bat Mops plicatus feeds primarily on planthoppers, a major pest for rice farmers in Southeast Asia. This bat may help limit the spread of planthoppers by feeding on wind-dispersed individuals at high altitudes, providing an important ecosystem service. However, its foraging behavior during peak planthopper activity remains poorly understood. Therefore, we examined the three-dimensional foraging behavior of M. plicatus using miniaturized Global Positioning System loggers during peak emergence of planthoppers. We predicted that bats would spend most foraging time at high altitudes (i.e., > 110 m above ground), and use relatively large foraging ranges. Furthermore, we predicted that low-altitude flights would occur in paddy fields and high-altitude flights above forested sites on mountain ridges. Six of the 11 tracked bats used large foraging areas, covering between 40 to 1,740 km2 during a single night. The median distance bats traveled per foraging trip was 60 km (range 27–217 km), with a median maximum distance from the cave roost of 26 km (range 13–95 km). Bats flew at a median altitude of 146 m above ground, yet occasionally reached more than 1,600 m above ground. Our results confirmed that M. plicatus foraged primarily at high altitudes for about 57% of their time. They preferred paddy fields and forests while avoiding water bodies. With its high-altitude flights and preference for planthoppers as prey, M. plicatus could help limit the spread of a major rice pest in Southeast Asia. Protecting this bat species could help support rice harvests throughout the region. [ABSTRACT FROM AUTHOR]

Successful predation by piscivores is driven by both prey and environment. Effects of light intensity and habitat on behavior of juvenile muskellunge Esox masquinongy were evaluated as predators foraged on either bluegill Lepomis macrochirus or golden shiner Notemigonus crysoleucas in laboratory experiments. Three light intensities were simulated (day, twilight, and night) in the presence or absence of treatments of simulated vegetation. Muskellunge behaviors for locating prey were shaped by light intensity and vegetation, while strategies for capturing prey remained consistent across all conditions. Similarly, muskellunge capture efficiency and success did not depend on light intensity or vegetation, and few interactions occurred between predator foraging behavior and these factors. While prey had difficulty maintaining anti-predator behavior with decreasing light, muskellunge did not exploit increased prey vulnerability with increased captures. Rather, prey species was a better predictor of predator success as bluegill were less vulnerable to predation than golden shiner. Our results indicate that, due to a slow stalking or ambush strategy resulting in low capture rates, foraging throughout a large portion of the diel cycle may be an adaptive response to increase prey capture opportunities for juvenile muskellunge. [ABSTRACT FROM AUTHOR]

Evaluating the dynamic co-evolution and feedback mechanisms within socio-ecological systems is crucial for determining the resilience and sustainability of environmental governance strategies. The grass-livestock system, as a complex entity encompassing livestock nutrition, foraging behavior, vegetation ecology, pastoralists' economic income, and policy interventions, indicates that any change in a single element may trigger a chain reaction within the system. This paper uses a system dynamics approach to construct a simulation model of the grass-livestock system in alpine pastoral areas, simulating the long-term dynamic co-evolution of the socio-ecological system in the Qilian Mountains region of China. Four optimization schemes were proposed, and the synergistic development of the grass-livestock system in alpine pastoral areas under each scheme was simulated. The results show that, under the premise of sustainable use of grazing-based artificial grassland, the combination of reasonable use of fenced grasslands and cooperative management by pastoralists can effectively control livestock numbers, ensure pastoralists' income, and maintain grassland quality within the next 20 years, thereby achieving coordinated socio-economic and ecological development. Additionally, optimizing feed supply can significantly improve grass production, livestock weight, and income. Therefore, it is recommended that alpine pastoral areas prioritize both grassland ecological management and development, adopt grassland restoration technologies, strengthen the management of artificial grasslands, set reasonable grazing bans, develop pastoralist cooperative organizations and design internal operational mechanisms. [ABSTRACT FROM AUTHOR]

Optimal foraging theory posits that foragers adjust their movements based on prey abundance to optimize food intake. While extensively studied in terrestrial and marine environments, aerial foraging has remained relatively unexplored due to technological limitations. This study, uniquely combining BirdScan-MR1 radar and the Advanced Tracking and Localization of Animals in Real-Life Systems biotelemetry system, investigates the foraging dynamics of Little Swifts (Apus affinis) in response to insect movements over Israel’s Hula Valley. Insect movement traffic rate (MoTR) substantially varied across days, strongly influencing swift movement. On days with high MoTR, swifts exhibited reduced flight distance, increased colony visit rate, and earlier arrivals at the breeding colony, reflecting a dynamic response to prey availability. However, no significant effects were observed in total foraging duration, flight speed, or daily route length. Notably, as insect abundance increased, inter-individual distances decreased. These findings suggest that Little Swifts optimize their foraging behavior in relation to aerial insect abundance, likely influencing reproductive success and population dynamics. The integration of radar technology and biotelemetry systems provides a unique perspective on the interactions between aerial insectivores and their prey, contributing to a comprehensive understanding of optimal foraging strategies in diverse environments. [ABSTRACT FROM AUTHOR]

Behavioral flexibility and the ability to respond appropriately to anthropogenic cues that signal potential threats or rewards may promote the success of wild animals in the urban environment. Here, we examine the behavioral responses to anthropogenic cues of free-living American crows (Corvus brachyrhynchos), an opportunistic scavenger and common urban exploiter. Specifically, we tested the hypotheses that crows would more readily approach (1) novel objects and anthropogenic food when in close proximity to trash cans, and (2) paper bags with hidden food rewards when closer to a McDonald's restaurant, due to their associations of food with these cues. In addition, we examined the preference of crows for bags marked with a McDonald's logo vs. unmarked bags, hypothesizing that crows closer to McDonald's would be more likely to approach the labeled bag because of its familiarity. Consistent with our expectations, crows exhibited a lower approach latency to anthropogenic food and novel objects in close proximity to trash cans. Likewise, they were more likely to approach paper bags when in proximity to a McDonald's restaurant, but they showed no preference for bags with a McDonald's logo. Overall, we found evidence that the foraging behavior of crows varied in the presence of specific anthropogenic cues and that these responses depended on their probable cue familiarity. Their ability to use anthropogenic cues specific to the local environment, combined with their exploitation of human food resources, likely contributes to the success of the American crow in the city. [ABSTRACT FROM AUTHOR]

Ultrasonic flowmeters are widely used in energy and control applications, providing accurate and fast measurement of fluid flow rates. This paper proposes a denoising method based on the goose optimization algorithm, a nature-inspired optimization method mimicking the foraging behavior of goose. GO optimizes the penalty factor and decomposition layer number of variational modal decomposition, resulting in the GO-VMD approach. Decomposed modal components are further denoised using an improved wavelet thresholding method. The algorithm is compared with existing methods, such as high-frequency ultrasonic signal processing, and experimental results show that it improves the signal-to-noise ratio by 8%, reduces root mean square error by 5%, retains more useful information, and achieves significant denoising results. [ABSTRACT FROM AUTHOR]

Acoustic monitoring facilitates the detailed study of herbivore grazing by generating a timeline of sound bursts associated with jaw movements (JMs) that perform bite or chew actions. The unclassified stream of JM events was used here in an observational study to explore the notion of "grazing time". Working with shepherded goat herds in a wooded landscape, a horn-based acoustic sensor with a vibration-type microphone was deployed on a volunteer animal along each of 12 foraging routes. The software-generated timeline of unclassified JMs contained a total of 334,582 events. After excluding rumination bouts, minutely JM rates showed a broad, non-normal distribution, with an overall mean of 61 JM min−1. The frequency distribution of inter-JM interval values scaled logarithmically, with a peak in the region of 0.43 s representing a baseline interval that generates the unconstrained, more-or-less regular, rhythm of jaw movement (≈140 JM min−1). This rhythm was punctuated by interruptions, for which duration scaled logarithmically, and which were primarily related to the search phase of the intake process. The empirical time accumulation curve shows the contribution of the inter-JM interval to the total foraging time and provides a penetrating profile of how the animal interacted with the foraging environment. The sum total of time along a foraging route spent at a near-potential JM rate was only ≈1 h, whereas sub-potential rates containing intervals as long as ≈30 s accounted for the bulk of the foraging route. The dimensionless behavioral grazing intensity was defined as the product of the number of ingestive JMs performed and the baseline interval, divided by the duration of the foraging route (excluding rumination). Values were mostly <0.5 for the foraging routes examined. This has implications for how animal presence should be translated to grazing pressure and for how long animals need to forage to meet their nutritional requirements. [ABSTRACT FROM AUTHOR]

Background and Aims Pollinators provide critical ecosystem services, maintaining biodiversity and benefitting global food production. However, plants, pollinators and their mutualistic interactions can be affected by drought, which has increased in severity and frequency under climate change. Using two annual, insect-pollinated wildflowers (Phacelia campanularia and Nemophila menziesii), we asked how drought impacts floral traits and foraging preferences of a solitary bee (Osmia lignaria) and explored potential implications for plant reproduction. Methods In greenhouses, we subjected plants experimentally to drought to induce water stress, as verified by leaf water potential. To assess the impact of drought on floral traits, we measured flower size, floral display size, nectar volume and nectar sugar concentration. To explore how drought-induced effects on floral traits affected bee foraging preferences, we performed choice trials. Individual female bees were placed into foraging arenas with two conspecific plants, one droughted and one non-droughted, and were allowed to forage freely. Key Results We determined that P. campanularia is more drought tolerant than N. menziesii , based on measures of turgor loss point, and confirmed that droughted plants were more drought stressed than non-droughted plants. For droughted plants of both species, the floral display size was reduced and the flowers were smaller and produced less, more-concentrated nectar. We found that bees preferred non-droughted flowers of N. menziesii. However, bee preference for non-droughted P. campanularia flowers depended on the time of day and was detected only in the afternoon. Conclusions Our findings indicate that bees prefer to visit non-droughted flowers, probably reducing pollination success for drought-stressed plants. Lack of preference for non-droughted P. campanularia flowers in the morning might reflect the higher drought tolerance of this species. This work highlights the potentially intersecting, short-term physiological and pollinator behavioural responses to drought and suggests that such responses might reshape plant–pollinator interactions, ultimately reducing reproductive output for less drought-tolerant wildflowers. [ABSTRACT FROM AUTHOR]

Breeding seabirds are required to balance between feeding their chicks and maintaining their body condition. Adélie penguins (Pygoscelis adeliae), a keystone species of the Antarctic ecosystem, have foraging behavioral flexibility that depends on the marine environment and own body condition. This study collected tracking data and weight measurements from 47 brooding penguins during two breeding seasons at Cape Hallett (72°19´S, 170°12´E), Ross Sea. In 2021, the breeding season with a high sea ice concentration, penguins had lower body weights during the early guarding period compared to the body weights of the penguins in 2022. Penguins performed three types of foraging trips - ice hole trips, ice edge trips, and pack ice trips—during the 2021 breeding season. However, in the season characterized by a low sea ice concentration (2022), most of the foraging trips were pack ice trips. Furthermore, penguins performed relatively shorter pack ice trips and had lower foraging efforts than they did in 2021. On the other hand, we found that penguins with higher initial weights lost more weight, where for every additional 1 kg of weight, individuals lost 360 g more during the tracking period. We suggest that penguins use selective foraging strategies to adapt to their situation. Additionally, they regulate their food intake for raising chicks based on their body condition. In summary, our findings suggest how Adélie penguins determine foraging strategies and allocating food according to the marine environment and their body condition. [ABSTRACT FROM AUTHOR]

[Display omitted] • Toll-like receptor signaling in neurons limits C. elegans foraging behavior during low hunger states. • Toll-like receptor signaling through the p38 MAPK PMK-1 is attenuated during high hunger states to promote foraging. • Neuro-immune signaling can modulate risk aversion during complex feeding behaviors. Animals face the risk of encountering pathogenic microbes while foraging for resources. Assessing the risk of nutrition vs. infection can result in the behavioral regulation of immune processes. Behavioral immunity in the nematode roundworm Caenorhabditis elegans (C. elegans) is regulated, in part, by the innate immune molecule TOL-1: a homolog of vertebrate Toll-like Receptor (TLR) proteins that influences C. elegans pathogen avoidance behaviors by promoting the development of CO 2 -detecting chemosensory neurons. While TOL-1′s role in pathogen avoidance is well established, its role in an opposing behavior – foraging – has not been examined. In addition to pathogenic bacteria, preferred food for C. elegans , such as Escherichia coli (E. coli) , create significant and aversive environmental CO 2 levels which may limit feeding behaviors in a tol-1 dependent manner. We have found that in addition to conferring antibacterial immunity, TOL-1 signals in neurons through the p38 MAPK PMK-1 to promote turning behavior and limit foraging when food is abundant and that the anorectic TOL-1/PMK-1 pathway is attenuated during starvation to promote foraging. These data highlight the dynamic role of a conserved innate immune cascade in neurons during both high and low hunger states and identify mechanisms underlying the neuro-immune control of feeding strategies. [ABSTRACT FROM AUTHOR]

Avian excavators (woodpeckers and other species) select nest sites based on the characteristics of the nest patch, nest tree, and substrate. These characteristics could increase foraging opportunities or reduce the risk of predation, but there is also a potentially important role for wood hardness in restricting nest-site selection, a role that has been little explored and is expected to vary among species according to their ability to excavate. We examined patterns of nest-site selection in 8 woodpecker species in the humid Chaco of South America, where the dominant trees have extremely hard wood. We hypothesized that (1) wood hardness is the main factor driving the selection of excavation sites, and (2) interspecific variation in body size and foraging behavior (traits frequently related to excavation ability) explain interspecific variation in the wood hardness of excavated nest substrates. From 2016 to 2019 in well-preserved forests of the Argentine Chaco, we compared nesting cavities excavated in wood (cases; n  = 42) vs. potential wood substrates without cavities (matched controls) and made 187 focal observations of foraging woodpeckers. Woodpeckers selected nesting substrates with softer heartwood than potential substrates, regardless of any other characteristics of the tree or nest patch. Wood hardness around nest cavities increased with body size and the prevalence of chiseling during foraging, traits that were positively correlated. Woodpeckers often excavated in Prosopis spp. (Algarrobos) but rarely in Schinopsis balansae (Quebracho), a tree with exceptionally hard internal wood, in which cavity adopters frequently nest in non-excavated cavities. Wood hardness is critical to assessing the role of woodpeckers as cavity facilitators, understanding the costs and benefits of excavation, and interpreting excavation patterns across species and forests globally. [ABSTRACT FROM AUTHOR]

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To enhance the accuracy of CNC machine tool fault diagnosis, this study proposes an intelligent optimization method based on the combination of Particle Swarm Optimization (PSO) and Bacterial Foraging Algorithm (BFA), referred to as PSO-BFA. By simulating the local foraging behavior of bacteria, the PSO-BFA algorithm demonstrates characteristics of local convergence, replicability, and migratory properties during parameter selection, effectively improving the local optimization capability and fitness value of the model. This leads to faster convergence to the optimal solution in the fault data training process. The study utilizes a Deep Confidence Network (DCN) model, known for its strong adjustability of model structure, for training the fault feature set. The PSO algorithm is employed to search for the optimal value in the global range. Simulation data indicate that the PSO-BFA intelligent optimization method significantly outperforms traditional swarm intelligence methods in multi-fault diagnosis and classification, achieving the peak fitting value in fewer iterations. [ABSTRACT FROM AUTHOR]

To maximize energy available for foraging or reproduction, optimality theory suggests individuals allocate energy toward defensive behaviors equivalent to risk of predation. In this framework, repeat encounters with humans by wildlife that do not reduce individual fitness could result in a decreased defensive response toward humans in subsequent encounters. We investigated whether individual experience influenced the defensive behaviors and frequency of site use of foraging eastern copperheads (Agkistrodon contortrix) at Koomer Ridge Campground in the Daniel Boone National Forest, Kentucky. Beginning in 2015, this site has been used for annual mark-recapture studies of copperhead foraging ecology as they predate emerging annual cicadas (Neotibicen tibicen). Using a standardized behavioral trial, we tested how copperhead defensive behavior toward humans was influenced by capture history, body size, and soil temperature. Model averaging results indicated that the overall intensity of copperhead defensive response to humans increased with capture history length, and soil temperature was positively associated with likelihood to respond when touched. Number of years recaptured was a significant, positive predictor of foraging frequency in 2022. Therefore, copperheads with longer capture histories visit the site to forage more frequently and are more willing to defend their opportunity to forage, suggesting a degree of acquired tolerance absent from naïve snakes that fled readily. Collectively, these results provide evidence that eastern copperheads at our site modulate their foraging and defensive behavior based on previous capture experience to more efficiently predate a seasonally abundant prey item. Significance: All species are faced with tradeoffs between foraging and avoiding predation. Although the decision of energetic investment between behaviors has been the subject of considerable research, the extent to which an individual's experience plays a role in this decision-making process remains unclear, particularly for cryptic taxa like squamates. Using a long-term research site where eastern copperheads (Agkistrodon contortrix) seasonally gather to predate emerging cicadas, we studied the foraging and defensive behaviors of individuals with known capture histories to determine if capture history influenced foraging frequency and the initiation and magnitude of defensive behavior towards humans. Through standardized behavioral trials and nightly monitoring of site foraging activity we documented that copperheads with longer capture histories foraged for cicadas more frequently and were more willing to defend their foraging opportunity to human approach than less experienced individuals. [ABSTRACT FROM AUTHOR]

Polymorphisms are maintained over time by trade-offs that alternatively favor morphs over space or time. In a polyphenic population of amphibians (Arizona tiger salamander; Ambystoma mavortium nebulosum), two morphs—paedomorphs and metamorphs—exhibit a trade-off in dispersal capacity. Larvae select between two discrete ontogenetic pathways based on environmental cues—adult paedomorphs remain in their permanent, natal pond, while adult metamorphs disperse between ponds of varying hydroperiods and overwinter in the terrestrial environment. This polyphenism is maintained in part by sex-specific reproductive advantages within each morph, with paedomorphic males achieving more reproductive opportunities and metamorphic females achieving higher egg production. In this study, we examined the role of a high-quality, primary prey taxon (fairy shrimp)—which is accessible to metamorphs only—in balancing the sex-specific component of this dispersal trade-off. Among the 95 metamorphs for which we evaluated diet and body condition, we found that most of the high-condition individuals were females that contained predominantly fairy shrimp in their stomachs. In addition, females specialized on fairy shrimp at much lower fairy shrimp densities than males, indicating that the consumption of this prey taxon may have differential fitness benefits across metamorph sexes. Our findings align with the expectations of parental investment theory, in which female reproductive success is most limited by the energetic resources necessary for egg production, while male reproductive success is limited predominantly by access to females. Significance statement: Polymorphisms are a common source of phenotypic diversity in animal populations that are often maintained over time by trade-offs among morphs. In a subalpine amphibian population that exhibits a dispersal polyphenism, the dispersing morph (metamorph) can leave natal ponds and access a high-quality, ephemeral food resource (fairy shrimp) in ponds of nonpermanent hydroperiods. In this study, we quantify the spatiotemporal availability of this focal prey taxon and examine whether sex-specific foraging behavior among metamorphs could contribute to the persistence of this polyphenism. Our results suggest that fairy shrimp consumption allows metamorphs to realize benefits of the dispersal trade-off through high female fecundity. These findings emphasize the importance of considering intrapopulation variation in functional responses and how the behavior can contribute to the maintenance of polymorphisms. [ABSTRACT FROM AUTHOR]

The phytoseiid predatory mite Neoseiulus californicus (McGregor) is one of the most efficient biocontrol agents in integrated pest management (IPM) programs of greenhouse pests, with different feeding habits on pollen, thrips, eriophyiids, and spider mites. This study appraised the effect of the age and gender on functional response and age on numerical response of N. californicus fed on larvae and protonymph of Tetranychus urticae Koch under laboratory conditions at 25 ± 1 ℃, 70 ± 5% RH and a photoperiod of 16L: 8D h. In the functional response test, the 2, 4, 8, 16, 32, 64, and 128 densities of prey were offered to 3, 5, 7, 10, 15, 20, 25, 30, 35 and 40-day-old ages of female and 7, 10, 15, 20, 25 and 30-day-old ages of male individuals of N. californicus. The logistic regression was used to recognize the type of functional response. Type II functional response was recognized for all ages of the male and female individuals of N. californicus. The highest predation rate, and searching efficiency (a) was observed in the middle ages of the predator. A significant increase in oviposition was shown with increasing T. urticae density and increasing ages of the predator. Furthermore, in the middle age with low prey density, the efficiency of conversion of ingested food (ECI) was the highest. The results of this study showed that the different ages of N. californicus are influencing factors on its predation capacity and oviposition rate. [ABSTRACT FROM AUTHOR]

Successful foraging of piscivores is often dependent upon light availability in their visual habitat and is often influenced by a number of abiotic and biotic factors. In north-temperate lakes, dissolved organic carbon concentrations vary greatly, thus likely influencing foraging success. To understand the impact this has on the walleye (Sander vitreus), we sought to study foraging success at various light intensities under physiologically relevant downwelling light conditions in a laboratory foraging arena. Using electroretinography to determine physiologically relevant light conditions in adult walleye, we found that fish exhibit broad spectral sensitivity that was greatest from 500 to 550 nm. Under optimal light conditions (525 nm), we next determined the reaction distance and foraging success of age-0 walleye at various light intensities. The average reaction distance of age-0 walleye increased rapidly from 12 cm in complete darkness to 27 cm at civil twilight (1 lx or 3.16 × 1013 photons m−2 s−1) and then plateaued, ranging from 28 to 30 cm at higher light intensities. Prey capture success of age-0 walleye was greatest under low light conditions, averaging 20.5% from nautical twilight to civil twilight at − 3° solar altitude (0.05–1 lx or 1.58 × 1011–3.16 × 1013 photons m−2 s−1) and declined to 10–12% as light intensity increased and in full darkness. Walleye may be best suited for environments with predominantly green downwelling light and age-0 foraging was most successful at nautical and civil twilight. In north-temperate lakes, dissolved organic carbon concentrations can fluctuate interannually due to climate change. Defining preferred juvenile walleye foraging conditions allows for predictions of climate change influences on walleye habitat and age-0 recruitment. [ABSTRACT FROM AUTHOR]

In many primate species, nest raiding is a form of opportunistic foraging behavior designed to acquire protein-rich eggs and nestlings. In urban environments, this is a significant cause of nest failure in birds. Here, we describe nest raiding and egg predation in bonnet macaques (Macaca radiata) inhabiting a suburban area of Salem, Tamil Nadu, India. During nest raiding, large-billed crows (Corvus macrorhynchos) and house crows (Corvus splendens), actively defended their nest from the macaques. When several macaque foragers jointly raided the nest, they were successful in obtaining and consuming the eggs. In contrast, when a solitary macaque attempted to raid the nest, it was unsuccessful. Bird size appeared to play an important role in nest defense. Small birds, such as the scaly breasted munia (Lonchura punctulata) and the purple sunbird (Cinnyris asiaticus) were not able to protect their nests from lone bonnet macaques. These observations indicate that in urban landscapes, bonnet macaques are egg predators of many bird species. When macaques coordinate their actions and forage in small subgroups, they were more successful in preying on the eggs of larger-bodied bird species. [ABSTRACT FROM AUTHOR]

Introduction: Urbanization, characterized by the rapid expansion of human settlements and development, greatly impacts biodiversity, especially where developments and human settlements are not guided by proper environmental consideration. Methods: We used data collected through citizen science projects under the African Bird Atlas Project, based on standardized protocols to gather bird occurrence data. Species' ecological traits, related to foraging behavior, habitat speciality, and body mass, were analyzed to assess functional richness and functional diversity (FD) represented by Rao's quadratic entropy. Geospatial data, including the Global Human Settlement Layer and Human Modification Index (HMI), along with the probability of urban expansion up to 2030, were integrated to examine the impact of urbanization using Bayesian models. Results: Our findings reveal a marked decline in taxonomic richness, diversity, and functional richness associated with increasing urbanization and human modification, with a similar pattern observed along the gradient from mostly uninhabited areas to cities. However, FD increased with urbanization from uninhabited areas to cities. The relationship between FD and HMI was nonlinear, showing an initial negative trend that became positive as HMI increased. This suggests a transition in bird communities, where generalist species thrive in urban environments, potentially replacing specialized species and leading to functional redundancy. Discussion: Despite the complex relationships observed, urbanization has a predominantly negative impact on the richness and diversity of Afrotropical bird communities. The decline in avian diversity and functional richness has important implications for ecosystem functions and services, crucial for biodiversity and human well-being. Our research provides valuable insights into the ecological impacts of urban expansion and emphasizes the importance of preserving natural habitats amidst growing urban landscapes. Summary of taxonomic and functional richness and diversity trends along the urbanization gradient. Taxonomic Richness, Functional Richness, and Taxonomic Diversity decrease with increasing urbanization, as indicated by the downward red arrows (highest in uninhabited and rural areas). Functional Diversity, as measured by Rao's Quadratic Entropy, increases in more urbanized environments, as shown by the upward blue arrow (highest in cities). [ABSTRACT FROM AUTHOR]

Strawberries are a widely cultivated greenhouse crop in China, primarily pollinated by honeybees, in accordance with traditional planting practices and local conditions. Extensive research has demonstrated that cross-pollination benefits numerous strawberry cultivars, leading to enhanced yield through the interplanting of different cultivars. However, the high costs associated with cultivation have hindered systematic research on the design of interplanting strategies. In this study, we utilized a simulation model to investigate how to leverage honeybee natural foraging behavior to improve pollination efficiency and explore fruit weight under various interplanting strategies within a greenhouse. Our findings indicate that adopting an alternating planting approach for different cultivars within the same bed effectively facilitates cross-pollination, leading to increased strawberry fruit yield. Additionally, dividing the strawberry plants into two batches and staggering their planting time helps mitigating the pressure of competition for bee pollination during peak blooming period, consequently contributing to enhanced yield. These proposed planting strategies offer valuable cultivation suggestions for farmers in some remote areas in China who still rely on honeybees as primary pollinators. [ABSTRACT FROM AUTHOR]

The appetite of honeybees for food is crucial to their survival and reproduction, as they sustain their entire colony by collecting pollen and nectar for nutrients. Dopamine, an important neurotransmitter, regulates appetite and satiety. However, how dopamine regulates honeybee foraging behavior remains unexplored. In this study, we investigated dopamine expression in 23-day-old Apis mellifera under different food-wanting conditions and identified differentially expressed genes (DEGs) in the brains of honeybees using RNA sequencing technology. We showed that dopamine levels in honeybees starved for 2 h were higher than those sated after 2 h of starvation. RNA-seq results revealed there were differences in the expression of cytochrome P450-dependent monooxygenase (CYP9Q1) in honeybees, which regulated the sucrose sensitivity of honeybees under different intake states. Furthermore, CYP9Q1 targeted the expression of the insulin receptor substrate (IRS) to promote dopamine synthesis. Our findings emphasize the relationship between dopamine and honeybees' desire for food at the molecular level, providing a reference for further exploring the mechanism of food wanting. [ABSTRACT FROM AUTHOR]

ABSTRACT The conspicuous abdominal spines in females of Micrathena spiders have evolved independently in several species within the genus. Like other orb‐web spiders, Micrathena species can serve as prey to parasitoid mud‐dauber wasps, which paralyzes the spiders and inserts them into their nests to serve as food to their larvae. Based on this fact, some studies suggest that Micrathena spines evolved as an antipredator defense against the wasp. However, there is no direct evidence of how the spines could act to avoid the wasp behavior. Here, we present two distinct records involving an Amazonian species of spiny spider, Micrathena schreibersi, where the abdominal spines act as a mechanical barrier against mud‐dauber wasps (Sceliphron spp.). These spines prevented the wasps from completely inserting the paralyzed spiders into their tubular nests, forcing the wasps to alter the opening shape to close it. In our second record, the wasp was not able to completely close the nest, leading to predation of her offspring by ants. We discuss the ecological implications of this potential defense trait for both species and propose future hypotheses to further elucidate how these spines may have evolved based on the foraging behavior of mud‐dauber wasps. [ABSTRACT FROM AUTHOR]

A species' diet is highly dependent on the availability of food resources in space and time, as well as on intrinsic factors such as sex or age. Accurate assessments of variations in the diet composition of bird populations across spatial scales, seasons and demographic groups are essential not only for understanding the basic ecology of species, but also for the conservation of endangered ones. However, our current knowledge about how birds' diet change according to spatio-temporal variations or intrinsic factors is very limited. Here, we used a multi-marker metabarcoding approach to characterize the diet of a declining shrub-steppe passerine, the Dupont's Lark (Chersophilus duponti), throughout a large part of its global distribution range. We also investigated spatial, phenological and sexual variations in its diet. Using markers from two genomic regions (18S and COI), we analyzed fecal samples from 303 adult Dupont's larks from Morocco and Spain during the breeding and non-breeding seasons. Overall, arthropods from the orders Coleoptera, Lepidoptera, Julida and Orthoptera were the main prey consumed by Dupont's Larks. We found that Dupont's Lark diet varied spatially, as well as temporally, reflecting dietary plasticity in response to changes in prey availability across landscapes and the species' phenological periods. High dietary overlap and no differences between sexes were observed, suggesting similar foraging behavior and nutritional requirements in both sexes. This is the first study providing detailed information on Dupont's Lark food ecology over much of its distribution, which is fundamental for the management and conservation of this declining steppe species. [ABSTRACT FROM AUTHOR]

Climate warming can precipitate mismatches in plant-pollinator interactions by altering their phenologies of both parties, impacting ecosystem services. While most studies have focused on long-term, seasonal phenological shifts, the effect of warming on short-term phenological match-mismatch in these interactions remains unclear. Here, we investigate how experimental warming affects within-day foraging behavior of the honey bee (Apis mellifera) and plant anthesis, and whether the resulting changes in bee pollen composition, in terms of the relative abundance of pollen from different plant species, influences larval development. Experimental warming advanced both the within-day foraging by bees and anthesis of Bidens pilosa—the predominant pollen source among all plant species represented in the collected pollen. Through experimental manipulation of pollen composition, we demonstrated that an increased proportion of B. pilosa pollen in the diet enhanced bee larval growth efficiency. Overall, our study demonstrates that warming may influence pollinator interactions with the many plant species by affecting pollinator behaviors and plant anthesis on short-term temporal scales, with potential implications for pollinator larval development. [ABSTRACT FROM AUTHOR]

Knowledge of how animals respond to weather and changes in their physical environment is increasingly important, given the higher frequency of extreme weather recorded in recent years and its forecasted increase globally. 1,2 Even species considered to be highly adapted to extremes of weather, as albatrosses are to strong winds, 3,4,5 may be disadvantaged by shifts in those extremes. Tracked albatrosses were shown recently to avoid storms and the strongest associated winds. 6 The drivers of this response are so far unknown, though we hypothesize that turbulent storm conditions restrict foraging success, possibly by reducing the detectability or accessibility of food, and albatrosses divert toward more profitable conditions where possible. We tested the impact of the physical environment—wind speed, rainfall, water clarity, and time of day—on feeding activity and success of two species of albatrosses with contrasting foraging strategies. We tracked 33 wandering and 48 black-browed albatrosses from Bird Island (South Georgia) with GPS and immersion loggers, and 19 and 7 individuals, respectively, with stomach-temperature loggers to record ingestions, providing an in-depth picture of foraging behavior. Reduced foraging profitability (probability of prey capture and overall mass) was associated with stormy conditions, specifically strong winds and heavy rain in surface-seizing wandering albatrosses, and the probability of prey capture was reduced in strong winds in black-browed albatrosses. We show that even highly wind-adapted species may frequently encounter conditions that make foraging difficult, giving context to storm avoidance in albatrosses. [Display omitted] [Display omitted] • Albatrosses exploit wind for flight but seemingly avoid the strongest winds in storms • We use multi-stream biologging data to relate albatross foraging to the environment • Our two study species experience reduced foraging success in stormy conditions • Wandering albatross land repeatedly in very strong winds, possibly to avoid injury Strong winds reduce the energy required for flight and takeoff in albatrosses; however, little is known about how wind impacts other behaviors, such as foraging. Darby et al. combined at-sea behavior and stomach-temperature data from two species of albatross to demonstrate the negative impact of stormy weather on foraging behavior and prey capture. [ABSTRACT FROM AUTHOR]

Spatial patterns in topography and forage distribution significantly influence the movements and choices of large herbivores. However, understanding the foraging strategies of free-grazing herbivores at different temporal and spatial scales remains limited, as different behavioral decisions can apply at different hierarchical levels. This study investigates the fine-scale foraging strategies of the Plains Zebra (Equus quagga) in a South African savanna, with a specific focus on their selection of green vegetation at the plant and feeding patch levels. We used the Normalized Difference Vegetation Index as a proxy for vegetation productivity and quality. Our findings reveal that zebras adapted their foraging strategies according to scale and season. During the late-dry season and early-wet season, selection for greenness was at both the grass tuft and feeding site levels. In contrast, during the mid-dry season, selection was predominantly at the tuft level, focusing solely on greenness. These insights emphasize the importance of conducting multilevel studies when investigating factors influencing foraging decisions. Findings at 1 hierarchical level may not necessarily apply across other levels of investigation, highlighting the need for a nuanced and comprehensive approach to understanding the complex foraging behaviors of animals. [ABSTRACT FROM AUTHOR]

The olfaction in batoids have an important role for initial detection of the chemical stimulus produced by prey during the foraging activities. The present study relates the morphology of olfactory rosettes to the habitat use and feeding habits in four potamotrygonin species. The morphological and histological descriptions of the olfactory structures are provided, using preserved olfactory rosettes. A simpler structure of olfactory organs in Paratrygon sp. does not indicate a primary sensory role during the initial phase of its feeding behavior. In Potamotrygon wallacei, the largest surface area of primary lamellae suggests enhanced olfactory sensitivity related to its generalist feeding habits and complex substrate exploration. Although the gross morphology is similar, histological analyses revealed that the sensory and non-sensory regions present differences in epithelial cell composition among species, with variations in the secondary folds shape and the distribution of mucus cells. The simplicity of secondary folds in both Paratrygon sp. and Potamotrygon orbignyi probably is related to their specialized feeding habits, requiring fewer adaptations to detect different types of chemical stimuli. These findings provide insights into the functional morphology of olfactory organs in potamotrygonin stingrays and their ecological implications, evidencing the intricate sensory adaptations crucial for foraging success in diverse freshwater habitats. Additionally, it becomes necessary to take into account the contribution of all sensory systems to understand their foraging behavior. Nonetheless, the generalization of the morphological characteristics of olfactory organ in a potamotrygonin species requires caution, since morphological variations can be found, especially to widespread species. [ABSTRACT FROM AUTHOR]

The composition of assemblages, diet and behavior of waterbird species with similar ecological features are important aspects in the functioning of aquatic ecosystems. Closely related animal species often share resources such as space and food in ways that reduce competition, but if the diets of different species strongly overlap, interspecific competition may intensify. This analysis examined behavioral data relating to Great Egret, Little Egret, and Squacco Heron to explore their foraging efficiencies in rich aquatic habitats in an arid zone during post-breeding movements. The fieldwork was carried out in small estuaries of a Wadi on the southern coast of Oman. The frequency of interactions was the highest in Squacco Heron and the lowest in Great Egret. However, the differences in the numbers of inter- and intra-specific interactions between the 3 species were significant. Activity indices calculated for a 5-min period, i.e. the number of interactions (interaction index) and times of flying and walking (movement index) differed among the 3 species. The number of successful attacks was the highest in Squacco Heron, while the foraging effectiveness of Great Egret and Little Egret was similar. GLM analysis showed that only the movement index was significant, as it had a positive impact on individual foraging success. Great Egret caught more fish than the other 2 heron species which, in turn, caught a greater number of smaller prey items, mostly invertebrates. This study shows that heron species in the same rich habitat employ different foraging tactics. In comparison to the other two heron species, the foraging tactics of Squacco Heron seem to be the most susceptible to competition. However, its greater mobility and using different foraging tactics, enhance its foraging success. [ABSTRACT FROM AUTHOR]

Chironius snakes are typically arboreal or scansorial, usually foraging in trees or forest ground. Herein we report the foraging behavior of the vine snake Chironius brazili while hunting on the large hylid frog Bokermannohyla pseudopseudis on rocky surfaces in open habitats at the Chapada dos Veadeiros, Central Brazil. Snakes were able to locate frogs when they were basking over rock surfaces close to rivers or searching for them on rock crevices even in areas with strong water flux, close to waterfalls. We suggest that scansorial habits and the swimming abilities of Chironius species occurring in rocky montane habitats enable these snakes to feed on these large hylids. [ABSTRACT FROM AUTHOR]

Predators have evolved a variety of novel mechanisms for efficient prey location that rely on specific sensory modalities. Strike-induced chemosensory searching (SICS) is a behavior pattern common across squamate reptiles (snakes and lizards) where a series of specific searching behaviors are activated in the predator following the envenomating strike and immediate release of prey. Of all squamates, rattlesnakes (Crotalus spp.) have been studied most extensively for their SICS behavior, but field documentation of such behaviors is sparse and often lacking in detail. Our study took advantage of a wild population of Timber Rattlesnakes (Crotalus horridus) in the Ozark Mountains of northwest Arkansas. Individuals were implanted with radio transmitters as part of a larger study on the effects of supplemental rodent prey on the physiological ecology of C. horridus. From these supplemental feeding trials, we filmed n 5 10 successful episodes of SICS as rattlesnakes (n 5 7) struck, released, and relocated rodent prey. All rattlesnakes exhibited the typical phases of SICS (quiescence, searching, trailing), and though the duration of each phase did not differ, rates of tongue-flicking (RTF) and breathing significantly increased from quiescence to trailing. We noted rapid, shallow ventilation patterns in the rattlesnakes, burst-like ventilation (BLV), and propose that BLV functions to surveil volatile chemical cues in the environment. Rates of tongue-flicking are well known proxies for measuring vomerolfaction in squamates, and we suggest BLV may similarly serve as a proxy for estimating rates of olfaction. The short cycles of air exchange we quantified as BLV flush air across the olfactory epithelium and thus could serve to detect volatile chemical cues. Quantification of BLV may enable researchers to capture more information about the sensory processes involved in squamate foraging behavior. [ABSTRACT FROM AUTHOR]

This paper proposes a novel artificial bee colony with predation effect (ABCPE) algorithm for tuning a proportional integral derivative (PID) controller. The mathematical model of ABCPE algorithm to introduce predator effect in the foraging behavior of artificial bees colony algorithm has been formulated. The proposed algorithm has been tested on tuning problems of different process models. The simulation results reveal that the closed-loop responses are relatively fast and non-oscillatory as compared to the frequency response analysis method for reference tracking. Further, the results obtained using ABCPE are also compared with other evolutionary algorithms. The exhaustive analysis shows that the ABCPE-based solution approach leads to a set of tuning parameters having smaller overshoot, less setting time, and rise time compared to other solution approaches. The stability analysis using Nichols plot reveals that the phase margin of proposed algorithm is higher as compared to other tuning methods. Finally, the convergence behavior and robustness analysis reveals the effectiveness of the proposed approach to solve engineering design problems. [ABSTRACT FROM AUTHOR]

Simple Summary: We conducted an investigation into the foraging behavior of Dinoponera quadriceps, which is an ant species that forages solitarily. The ants were subjected to a range of foraging scenarios that included varying distances to food sources, differing prey sizes, and varying capture success rates. The findings revealed that these ants display a significant preference for returning to previously successful foraging sites, irrespective of the distance, prey size, or reward rate. Conversely, in instances where the ants were unsuccessful in capturing prey, they exhibited a heightened tendency to explore new foraging areas. When searching for food, animals often make decisions about where to go, how long to stay in a foraging area, and whether to return to the most recently visited spot. These decisions can be enhanced by cognitive traits and adjusted based on previous experience. In social insects, such as ants, foraging efficiency has an impact at both the individual and colony levels. The present study investigated the effect of the distance to, capture success, food size, and the reward rate on decisions of where to forage in Dinoponera quadriceps, a ponerine ant that forages solitarily and makes individual foraging decisions, in laboratory studies. We also investigated the influence of learning on the workers' performance over successive trips to search for food by measuring the patch residence time in each foraging trip. Four scenarios were created that differed in the food reward rates, the food size offered, and the distances from the colony to the food site. Our work demonstrated that as a general rule, the D. quadriceps workers return to the place where a prey item was found on the previous trip, regardless of the distance, food size, and reward rate. When the ants did not capture prey, they were more likely to change their route to search for food. Our results also indicated a learning process for the routes of exploration, as well as the food site conditions for exploration. After repeated trips, the foragers reduced the patch residence time in areas where they did not capture food and quickly changed foraging areas, increasing their foraging efficiency. [ABSTRACT FROM AUTHOR]

This study presents an innovative hybrid evolutionary algorithm that combines the Arctic Puffin Optimization (APO) algorithm with the JADE dynamic differential evolution framework. The APO algorithm, inspired by the foraging patterns of Arctic puffins, demonstrates certain challenges, including a tendency to converge prematurely at local minima, a slow rate of convergence, and an insufficient equilibrium between the exploration and exploitation processes. To mitigate these drawbacks, the proposed hybrid approach incorporates the dynamic features of JADE, which enhances the exploration–exploitation trade-off through adaptive parameter control and the use of an external archive. By synergizing the effective search mechanisms modeled after the foraging behavior of Arctic puffins with JADE's advanced dynamic strategies, this integration significantly improves global search efficiency and accelerates the convergence process. The effectiveness of APO-JADE is demonstrated through benchmark tests against well-known IEEE CEC 2022 unimodal and multimodal functions, showing superior performance over 32 compared optimization algorithms. Additionally, APO-JADE is applied to complex engineering design problems, including the optimization of engineering structures and mechanisms, revealing its practical utility in navigating challenging, multi-dimensional search spaces typically encountered in real-world engineering problems. The results confirm that APO-JADE outperformed all of the compared optimizers, effectively addressing the challenges of unknown and complex search areas in engineering design optimization. [ABSTRACT FROM AUTHOR]

There is a Bengali tradition of consuming palm "jaggery" (unrefined sugar made from the sap of Indian date palms, Phoenix sylvestris) as a sweetener. To obtain jaggery, people tap Indian date palms to extract the energy-rich phloem sap during the winter. In Bangladesh, people commonly cultivate Indian date palms in traditional agroforestry. We explored which bird species capitalize on the jaggery tradition by consuming sap from tapped Indian date palms on Nijhum Dweep, an island in the Bay of Bengal. Once each day for 30 d between December 2019 and February 2020, we quantified the presence of birds on 120 tapped palms along a 1 km transect. We observed 37 bird species in the palms, and 18 of them (49%) were seen to consume sap. Seven species had not previously been recorded as sap feeders. Among the 18 sap-consuming species, we categorized 5 species (Chestnut-tailed Starling Sturnia malabarica, Asian Pied Starling Gracupica contra, Jungle Myna Acridotheres fuscus, Red-vented Bulbul Pycnonotus cafer, and Black Drongo Dicrurus macrocercus) as constant consumers of date palm sap; 11 species as accidental sap consumers, and 2 species as accessory sap consumers. Insectivorous and omnivorous species accounted for 78% of the sap consumers (39% each), with granivorous and frugivorous species accounting for the remaining 22%. This study highlights date palm sap as a potentially significant winter food source for resident birds, and demonstrates birds' ability to utilize tapped palms as an anthropogenic food resource. [ABSTRACT FROM AUTHOR]

Australia is home to an incredible diversity of spiders, but much of their biology remains unstudied. The orb-weaving spiders (family Araneidae) are especially diverse and frequently encountered, yet the ecology of very few species has been explored. The common name "Australian garden orb-weaver" refers to several species, including Hortophora transmarina (Keyserling, 1865), found mostly along Australia's east coast, and Hortophora biapicata (L Koch, 1871), found mostly along Australia's south and south-eastern coasts. These two similar species are large, nocturnal orb-weavers that occupy a wide range of both natural and anthropogenically disturbed habitats. Here, I describe the general morphology, habitat use, diet and foraging behavior, key predators, laboratory rearing, and mating dynamics of these common but understudied spiders. This information was gathered via field observations, laboratory experiments, and literature reviews. These spiders provide a useful system for studying a number of aspects of spider biology, including mating systems, predation, anti-predator defences, and nocturnal behaviors. [ABSTRACT FROM AUTHOR]

Bees are essential pollinators for many plant species, but multiple threats exist to both managed and wild bee populations. Since bee nutrition is critical for hive and colony health, their innate foraging behaviors and food preferences are the subject of extensive study. Multiple approaches have been developed to assess bee foraging behavior and associated preferences, but these approaches are often labor-intensive and provide data on a limited number of parameters. In this manuscript, we present an improved method to quantify bee foraging preferences, including the design, build, and implementation of an inexpensive and automated feeding apparatus capable of recording (1) environmental conditions, (2) species and behavior through photos and videos, (3) foraging activity, and (4) food consumption. The efficacy of this apparatus is demonstrated through preference tests with artificial nectars, while also acknowledging the limitations of this approach. [ABSTRACT FROM AUTHOR]

Artificial light at night (ALAN) has become a potent pollutant in recent days that can manipulate the biology of both flora and fauna. In this context this paper deals with three types of light sources to know how they can alter the host plant choice, foraging and oviposition site selection of an Indian grasshopper Spathosternum prasiniferum. The results clearly showed that variation in light sources can definitely alter the foraging behavior of the test insects. The most interesting finding was of the egg laying response. It was evident that they preferred a warmer area for egg laying. As in the control sets the light source was the natural light only, the grasshoppers were found to lay eggs more on the marginal areas of the cages, while in case of the warm yellow light exposed sets it was more on the central part as the soil heated up in those areas. On the contrary in case of cool LED lights they got confused as those light sources never corresponded with heat. Even though the present paper deals with preliminary data, it could be safely stated that ALAN has an alarming impact on the ecology and behavior of acridid grasshoppers. [ABSTRACT FROM AUTHOR]

Predation events are an important key factor determining the survival and reproduction of prey species. To cope, prey species have evolved various anti‐predator strategies, including mechanisms for accurate predator identification and distinguishing predator types and risk levels. Birds rely on visual, auditory, and olfactory cues to perceive and categorize predators. However, previous studies have focused on single sensory modalities and have largely been conducted during breeding seasons. Thus, analyses of the accuracy and differences in predator recognition cues, especially during non‐breeding periods, are needed. In this study, predator recognition in Azure‐winged Magpies (Cyanopica cyanus) was evaluated during the non‐breeding season. We examined responses to two predators, Common Kestrel (Falco tinnunculus) and Domestic Cat (Felis catus), and two non‐predators, Oriental Magpie (Pica serica) and Oriental Turtle Dove (Streptopelia orientalis). Using specimens and playback experiment, the ability of Azure‐winged magpies to identify threats through both visual and auditory cues was evaluated. The results showed that Azure‐winged Magpies can identify predator types through both visual and auditory cues, accurately distinguish threat levels, and adjust their foraging behavior accordingly. Notably, they exhibited the strongest anti‐predator response to Domestic Cats (frequently encountered under natural conditions), as evidenced by longer observation times, shorter foraging duration, and quicker flight responses. The results indicate that Azure‐winged Magpies can correctly identify predator types and threat levels through both visual and auditory cues and exhibit stronger anti‐predator behaviors with increasing apparent threat levels. [ABSTRACT FROM AUTHOR]

Foraging during breeding is a demanding activity linked to breeding investment and possibly constrained by individual quality. Telomere length, the protective nucleoproteins located at the ends of the chromosomes, is considered a trait reflecting somatic maintenance and individual quality. Therefore, foraging effort and parental investment may be positively related to telomere length, if individuals with longer telomeres are of better quality and thus able to maintain better body condition and allocate more resources to parental activities. In the brown booby (Sula leucogaster), we investigated if telomere length is related to body mass (a proxy of condition) and whether variation in foraging behavior and provisioning effort is related to telomere length or body mass. Then, we explored whether variation in foraging and provisioning influences the chick mass growth rate. In 34 pairs nesting in Isla de San Jorge, in the Gulf of California, México, we sampled their blood to estimate telomere length, measured their body mass, and for 10 days, recorded their foraging behavior via global positioning system (GPS) loggers and their chick provisioning rate and chicks' mass growth rate. We found a positive relationship between parents' body mass and telomere length. Body mass did not affect foraging behavior. Females with longer telomeres were more prone to travel longer distances toward offshore and deeper waters than females with shorter telomeres. In contrast, males with longer telomere lengths performed more nearshore foraging trips than males with shorter telomeres. The chick provisioning rate was unrelated to telomere length or body mass, but females fed the chick at a rate 2.4 times greater than males. Females' offshore foraging, but not males', was positively related to chick mass growth rate. Our results suggest that individual quality, indicated by telomere length, is an important driver of sex‐specific, between‐individual variation in foraging behavior, indirectly affecting offspring condition. [ABSTRACT FROM AUTHOR]

We studied the foraging behavior of 29 radio-tagged individuals of the nectar-feeding phyllostomid bat Leptonycteris yerbabuenae using a short-range ATLAS tracking system as they fed at hummingbird feeders at three sites in Tucson, Arizona. We tested two hypotheses: (1) a spatiotemporal consistency hypothesis which predicts that bats will be consistent in their use of the feeders where they were captured for extended periods of time and (2) a temporal association hypothesis which predicts that bats captured together will continue to forage together on subsequent nights for extended periods of time. Our data supports hypothesis (1) but not hypothesis (2). Most of the tagged bats continued to visit the site where they were captured on most nights for up to 30 days, but pairs captured together did not continue to visit these sites together more often than expected by chance. From this, we infer that groups of bats that visit feeders do not do so as socially cohesive units. [ABSTRACT FROM AUTHOR]

This study describes the diet and trophic ecology of anurans from the Amazonian savanna in Amapá (Brazil). A total of 17 anuran species were collected (three bufonids, eight hylids, five leptodactylids, and one phyllomedusid), and their stomach contents revealed 17 prey items. Coleoptera, Hemiptera, and Acari had high indices of relative importance (IRI). Boana multifasciata exhibited the most diversified diet (11 prey). The trophic niche overlap was low (0.42), and trophic niche breadth varied between 0.31 (Rhinella major) and 1 (Leptodactylus podicipinus), suggesting generalist feeding behavior for these species. The null models indicated that the observed values differed significantly from expected values, demonstrating resource partitioning amongst anuran species in the Amapá Amazonian savanna, where competition does not seem to be the structuring agent. Group analysis among species revealed two main groups. Leptodactylus macrosternum and Dendropsophus walfordi showed the highest similarity of diet composition, while Leptodactylus pentadactylus and Boana raniceps showed the most dissimilar diet composition compared to other species. Anurans from the Amapá Amazonian savanna used various categories of prey, had high values of niche breadths, and overlapped on some of the most important categories of arthropods, coexisting in the same environment and can present different ways of accessing food resources influenced by the abundant prey and foraging behavior. This is the first study evaluating the diet of Brazilian frogs in the Amazonian savanna. [ABSTRACT FROM AUTHOR]

Compensatory density‐dependent (DD) processes play an integral role in fisheries management by underpinning fundamental population demographics. However, DD processes are often assessed only for specific life stages, likely resulting in misleading evaluations of population limitations. Here, we assessed the relative roles of intra‐ and inter‐life stage DD interactions in shaping the population dynamics of perennial freshwater fish with demographically open populations. Specifically, we monitored populations of amphidromous banded kōkopu (Galaxias fasciatus), giant kōkopu (Galaxias argenteus), and shortjaw kōkopu (Galaxias postvectis) in five streams where migratory post‐larvae are fished and in three no‐take ("closed") streams located on New Zealand's South Island for two years. Using mark‐recapture data, we investigated whether fishing altered densities of "small" (non‐territorial recruits ≤1‐year‐old) and "large" (territorial fish >1‐year‐old) kōkopu size classes, and how subsequent density shifts affected the apparent survival and growth of each class while controlling for other confounding factors (e.g., habitat characteristics). We found that closed areas had substantially greater biomass of small kōkopu, particularly following the two‐month fishing season. Despite this greater influx of recruits, there was no difference in the biomass of large kōkopu at the species level, or as a combined assemblage between stream types. This indicated that although fishing of post‐larvae reduced recruit influxes into adult habitats, there was no subsequent evidence of recruitment‐limitation within adult populations. Instead, kōkopu demographics were underpinned by intra‐ and inter‐life stage DD competition and predation. Greater large fish densities played a key role in regulating the survival, growth, and/or presence of various kōkopu classes. In contrast, greater small fish densities had positive effects on the growth of opportunistic and insectivorous congeners, likely due to cannibalism and altered foraging behaviors, respectively. Our study details the prominent role of intra‐ and inter‐life stage DD interactions in regulating the population dynamics of perennial migratory freshwater fishes, even in populations with inhibited recruit and juvenile availability. We emphasize the importance for fisheries management to implement recruitment dependencies and complex interactions between distinct life stages to avoid deleterious DD responses and ensure population persistence. [ABSTRACT FROM AUTHOR]