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Harvester ants are one of the most extensively studied groups of ants, especially the group foraging ants, Messor barbarus (Linnaeus, 1767), which construct long‐lasting trunk trails. Limited laboratory investigations have delved into head‐on encounters along foraging trails involving workers moving in opposing directions, with fewer corresponding studies conducted in the natural environment. To address this gap, we devised an in‐field experimental design to induce lane segregation on the foraging trunk trail of M. barbarus. Using an image‐based tracking method, we analyzed the foraging behavior of this species to assess the costs associated with head‐on encounters and to figure out the natural coexistence of outgoing and returning workers on a bidirectional route. Our results consistently reveal heightened straightness and speed in unidirectional test lanes, accompanied by an elevated foraging rate compared to bidirectional lanes. This suggests a potential impact of head‐on collisions on foraging behavior, especially on foraging efficiency. Additionally, Kinematic analysis revealed distinct movement patterns between outbound and inbound flows, particularly low speed and sinuous trajectories of inbounding unladen workers. The study of encounter rates in two traffic systems hints at the plausible utilization of individual memory by workers within trails, underscoring the pivotal role of encounters in information exchange and load transfer. [ABSTRACT FROM AUTHOR]

Bumblebees have become model organisms for cognitive ecology and social learning. Quantifying the foraging behavior of free-flying bees, however, remains a methodological challenge. We describe and provide the code for a method of studying bee free flying foraging behavior using the open source neural-network based markerless tracking software DeepLabCut. From videos of bees foraging in an arena we trained a neural network to accurately track the position of each bee. We then used this approach to study foraging behavior and show that the ratio between flying time and flower visiting time decreases over repeated foraging bouts, indicating increasing efficiency of bee foraging behavior with experience. Visit durations, a laborious metric to measure by hand, were significantly shorter on flowers that had previously been visited. This experiment illustrates the usefulness of DeepLabCut for objective quantification of behavior, and in this case study shows that previous experience increases bee foraging efficiency. [ABSTRACT FROM AUTHOR]

This experiment evaluated the effect of light manipulation on the behavior and welfare of broilers using 280-day-old Arbor-Acre chicks, which were weighed and assigned to 7 treatments having 4 replicates and 10 birds per replicate. The light treatments were as follows: white light (WH), blue light (BL), green (GR), blue light switched to green light at 14 days (2BG), green light switched to blue at 14 days (2GB), blue light switched to green light at 28 days (4BG), and green light switched to blue light at 28 days (4GB). Feeding, drinking, resting, standing, walking, foraging and preening behaviors were observed using the scan sampling method. Behavior and welfare parameters such as footpad dermatitis and hock burn were evaluated and analyzed in a Completely Randomized Design. The results showed that feeding behavior of birds of BL, 2BG, and 2GB treatment groups was significantly higher (P < 0.05) than those of WH and GR at the starter phase. At the finisher phase, resting behavior of birds of 4GB was similar to those of 2GB but higher than those of the other treatments. It was concluded that switching of light from green to blue (4GB) at four weeks of age fostered ideal behavior and stimulated growth in broilers but had no effect on welfare parameters. [ABSTRACT FROM AUTHOR]

Wildfires cause profound challenges for animals to overcome due to their reliance on vegetation. This study addresses the impact of three levels of forest burn severity (unburned, low, and high burn severity) on the foraging behavior of small mammals in the Pinaleño Mountains (AZ, USA) using the giving up density (GUD) experiment approach. Overall, burn severity affected the foraging behavior of small mammals that spent less time foraging in high burn severity patches. Vegetation characteristics influenced GUD differently based on the level of burn severity. Higher canopy cover was perceived as areas with a higher predation risk (higher GUD) in unburned and low burn severity patches, while cover provided by logs and shrubs decreased the GUD (increased foraging). This suggests a complicated interaction between horizontal (logs, grass, shrub cover) and vertical vegetation cover in relation to burn severity. Fires affected the foraging behavior of the small mammals but did not impact all species in the same way. Generalists, such as Peromyscus sp. and Tamias dorsalis, seemed to forage across all burn severities, while specialist species, such as tree squirrels, tended to avoid the high burn severity patches. Clarifying the complex impacts of fires on small mammals' foraging behaviors contributes to our understanding of the intricate interactions, at micro-habitat levels, between vegetation structure and the behavioral responses of animals and it can help managers to plan actions to reduce the negative impacts of wildfires. [ABSTRACT FROM AUTHOR]

Bumblebees carry out the complex task of foraging to provide for their colonies. They also conduct pollination, an ecosystem service of high importance to both wild plants and entomophilous crops. Insecticides can alter different aspects of bumblebee foraging behavior, including the motivation to leave the hive, finding the right flowers, handling flowers, and the ability to return to the colony. In the present study, we assessed how the neonicotinoid imidacloprid affects bumblebees' foraging behavior after exposure to four different treatment levels, including field‐realistic concentrations (0 [control], 1, 10, and 100 μg/L), through sucrose solution over 9 days. We observed the behavior of several free‐flying bumblebees simultaneously foraging on artificial flowers in a flight arena to register the bees' complex behavior postexposure. To conduct a detailed assessment of how insecticides affect bumblebee locomotor behavior, we used video cameras and analyzed the recordings using computer vision. We found that imidacloprid impaired learning and locomotor activity level when the bumblebees foraged on artificial flowers. We also found that imidacloprid exposure reduced sucrose solution intake and storage. By using automated analyses of video recordings of bumblebee behavior, we identified sublethal effects of imidacloprid exposure at field‐realistic doses. Specifically, we observed negative impacts on consumption of sucrose solution as well as on learning and locomotor activity level. Our results highlight the need for more multimodal approaches when assessing the sublethal effects of insecticides and plant protection products in general. Environ Toxicol Chem 2023;42:1337–1345. © 2023 SETAC [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the impact of different stocking populations of tilapia nilotica fish in their aquaculture on some maintenance behavior, performance, economic values, and hormonal concentration levels. On this research, 300 tilapia nilotica fish were distributed into different densities (15, 20,25 and30 fish per aquaria 40*30*80cm) 3 replica for each population and distributed in 70 Litter water in aquaria. 30 fish kept as aspare. After 2 weeks from the start of the experiment and at the end of the experimental periods, blood samples were collected for serum cortisol and growth hormones assay. From the obtained results we found that, the feeding and foraging behavior time and frequency (94.00+3.55&144.00+9.79) were improved with stocking density (15 fish in aquaria) and the aggressive behavior was at high level with overcrowding. (26.80+1.83&105.00+4.68), on the other hand the surfacing, swimming, and resting time were increased with higher stocking rate. The growth hormone was increased with decreased stocking density. The stress indicating hormone (cortisol) was increased with high stocking populations. The return and profit were significantly increase with decreased stocking density. [ABSTRACT FROM AUTHOR]

Danaus plexippus (monarch butterfly) populations in North America east of the Rocky Mountains are in decline due to loss of habitat containing Asclepias spp. (milkweed) and blooming forbs. To support D. plexippus recovery, habitat restoration efforts use seed mixes designed to maintain a diversity of species that bloom over the breeding and migration periods. The extent to which these species are uniquely attractive to foraging D. plexippus is unclear. We conducted observational studies at areas in Iowa USA with varying densities and diversities of Asclepias spp. and floral resources to help inform conservation management practices. Forty-two blooming forb species were present across four sites (2-4-ha) in Boone and Story counties from June through September in 2020. Many of the species present are commonly found in pollinator seed mixes. The number of blooming forbs species per site varied from 12 to 24 across the four months; the minimum and maximum density of species-specific inflorescences ranged from 8.45 to 36.3 inflorescence/m2. We observed D. plexippus nectaring on 27 of the 42 species across the sites. Based on total feeding events observed and the species-specific density of inflorescences, Asclepias syriaca, Asclepias verticillata, Helianthus grosseserratus, and Cirsium vulgare were favored for nectaring at each site where they were present. Additional species were favored in some, but not all, sites including Symphyotrichum pilosum, Eupatorium altissimum, Trifolium pratense, Echinacea pallida, and Verbena urticifolia. Findings suggest variation in preference may be due, in part, to site-specific and surrounding landscape features. Future studies on D. plexippus foraging behavior could address the interacting roles of habitat and landscape features, as well as species-specific flower size and shape, scent, nutrition, and nectar abundance. While forb utilization is likely influenced by site- and plant-specific features, preferred species we observed are typically included in recommended native seed mix designed to ensure blooms from June through September to support migratory and non-migratory, breeding D. plexippus. [ABSTRACT FROM AUTHOR]

The coexistence of competing species requires density feedbacks that have a larger effect on their own species' population growth than they do on others in the assembly. The feedbacks are often associated with behavioral tradeoffs that enable species to differentially exploit underlying axes of heterogeneity. Conjoining theories of species coexistence with foraging behavior and density‐dependent habitat selection reveals that such tradeoffs impinge on invasion probabilities and equilibrium dynamics emerging from species' differences in habitat use. The resulting habitat separation promotes coexistence by reducing the overall interaction among species. Differential habitat selection depends on the behavioral abilities of organisms to identify and exploit the most profitable habitats and resource patches. One might thus expect that each species will evolve behavioral types distinct from those of other potential competitors. Accordingly, we exposed four coexisting species in four genera of boreal rodents to open‐field tests. We used principal components (PC) to summarize their behaviors along three independent axes corresponding with clines of exploratory, vigilant, and apprehensive personalities. We confirmed that the axes represented repeatable behaviors (personalities) and assessed differences among species with a general linear model (GLM). The GLM revealed highly distinct differences among species, and between pairs of species, on each PC. Even so, it is difficult to infer the adaptive advantages of personality to the habitat segregation that reduces otherwise high interactions among species. Rather, personalities are best interpreted as co‐adaptive behaviors reflecting the complex of morphological, physiological and behavioral attributes that dictate tradeoffs and enable coexistence. [ABSTRACT FROM AUTHOR]

Giving-up densities (GUDs) are a frequently used technique that ascertains the value of a forager's patch use by measuring foraging harvest rate. However, it is not always feasible to measure GUDs due to issues such as non-target species accessing the food items and experimental designs not meeting all of the assumptions of GUDs. Under such circumstances, measuring activity densities can be a valuable alternative approach that can still address many of the same ecological questions as GUDs. Our objective was to design a feeder that enables the accurate measurement of ungulate habitat preference and space use by measuring activity densities and excluding non-target species from data collection. We conducted two experiments to measure the efficacy of our feeder design. The first measured the activity densities of white-tailed deer (Odocoileus virginianus) in three habitat types (forest, old-field, and ecotone). We then used trail cameras to monitor the frequency at which non-target species accessed our modified feeder design compared to a traditional feeding bin used in GUD experiments. We found that our feeders were able to discern habitat preference, and that white-tailed deer preferred to use the old-field habitat over the forest. From the camera-trap experiment, we found that non-target species foraged 173 times from feeding trays and zero times from our feeder design during asynchronous 5-day sampling periods. Additionally, our feeder design can be tailored to other ungulate species and provides a method that can quantify resource use and preference via measuring activity densities, while removing non-target species from data collection. Significance statement: Giving-up densities (GUDs) are a powerful behavioral indicator of foraging preference. Studies that measure GUDs frequently address the foraging behavior of individuals relative to habitat preference, predation risk, and other costs that can influence the fitness of a forager. However, many studies that measure GUDs deal with the issue of non-target species gaining access to the food source which can alter the results of a study and, in some cases, make results impossible to attain. The feeder design that we use for this experiment is suitable for measuring activity densities in place of GUDs for ungulate species and restricts access to non-target species that could alter the results of an experiment. Our approach provides a method for research that is related to foraging behavior and landscape use, and enables activity densities to be collected in circumstances where GUDs cannot. [ABSTRACT FROM AUTHOR]

Glucocorticoids (GCs) mediate responses to energetic and psychosocial challenges and are associated with behavioral adjustments that form part of an adaptive vertebrate stress response. GCs and behavior can indirectly influence each other, leading to either an intensification or attenuation of stress responses. Exploring these GC-behavior relationships may offer insights into the beneficial aspects of behavior and help identify coping mechanisms that potentially enhance individual fitness. We conducted a systematic review of the relationship between GCs and several behavioral traits, as described in the literature on captive and wild primates, and evaluated the effect of different categorical factors on these relationships using a meta-analytic approach. According to the type of behavior, we grouped statistical measures into affiliative, agonistic, anxiety-like, and foraging domains which were further differentiated into behavioral subgroups. We also categorized measures based on setting, method, sex and age of individuals, and sample matrix involved in each primary study. Overall, we found that some affiliative and foraging behaviors are associated with lower GC levels, while agonistic and anxiety-like behaviors are linked to higher GC levels. Specifically, non-sexual affiliation and energetically inexpensive activities were negatively related to GCs. In contrast, inter- and intragroup aggression, noncommunicative and self-directed behaviors, and energetically expensive activities were positively related to GCs. By demonstrating how certain social, ecological and intrinsic factors affect the GC-behavior relationships, our study helps elucidate the contexts that may alleviate or intensify the stress responses in non-human primates. • Social support and low-energy activities relate negatively to GCs. • High-energy activities, aggression and anxiety behaviors relate positively to GCs. • Energy resource indicators relate negatively to GCs. • Wild settings influence significantly agonism and GC relationships. • Captive settings influence significantly anxiety and GC relationships. [ABSTRACT FROM AUTHOR]

The pace-of-life syndrome theory suggests that species, populations, and individuals are positioned along a slow-fast pace-of-life continuum. However, whether and how individuals maintain a fast pace of life in a slow pace of life population remains unknown. In this study, the boldness and foraging behavior of Phrynocephalus vlangalii from Maduo (4250 m above sea level), a typical slow-paced population, were screened frequently. Both behaviors of P. vlangalii were significantly recurrent and linked with one another. Based on boldness and foraging behavior, the lizards were divided into positive and shy groups, and their gut microbial diversity were studied using 16S rRNA gene sequencing. No significant difference in a diversity was observed; however, a significant difference existed in the b diversity of gut microbes between the two groups. Principal coordinate analysis indicated that the gut microbes in the two groups were distinct. Linear discriminant analysis effect size determined that the shy group contained a more significant proportion of Rikenellaceae and Clostridia. In contrast, the positive group had a higher proportion of Verrucomicrobiota, Verrucomicrobiae, and Akkermansiaceae. Kyoto encyclopedia of genes and genomes pathway analysis revealed that biodegradation and metabolism, including lipid metabolism and glycan biosynthesis, were higher in the positive group; on the contrary, nucleotide metabolism and enzyme families were significantly higher in the shy group. The results showed that positive lizards had more beneficial intestinal microflora for lipid and glucose metabolism to satisfy their high metabolic energy demand, whereas shy lizards had more beneficial intestinal microflora for maintaining an elevated fasting blood glucose, a long life span, and a more stable metabolism to sustain their slow pace of life. In this study, we validate a strong relationship between the individual's pace-of-life traits and intestinal microbiota in P. vlangalii. Further, we demonstrate that gut microorganisms are essential in sustaining the energy-intensive personality traits at high altitudes. [ABSTRACT FROM AUTHOR]

Simple Summary: In the non-growing season, beavers fell woody plants that they primarily use as a food source. It is well known that parameters such as woody plant availability, trunk diameter, and distance of woody plants from water influence food selection. Less information is available on the felling of specific species in different stand types where different forest management takes place. This makes the beaver a conflict species that causes damage to commercial forests, and information on foraging behavior in relation to environmental factors is very important. Especially as beaver populations continue to increase. In the three types of forest stands (monoculture, mixed forest, and natural forest), species selection, the intensity of felling, the distance of felled woody plants, and trunk diameter vary. The beaver, which generally prefers non-commercial tree species (willow, poplar, etc.), also adapts to and uses commercial oaks in commercial forests. These are most preferred at stand ages up to twenty years, i.e., smaller diameters but greater stand densities. The results suggest that by using knowledge of foraging behavior, economically profitable species can be protected by encouraging the non-commercial species most preferred by beaver (predominantly willow) near the shoreline. In addition, the natural tree composition around rivers or lakes will be promoted. Native ecosystems have been transformed by humans into cultural landscapes, resulting in the disruption of natural interactions, with some species unable to adapt and disappearing from such landscapes. Other species were able to adapt their behavior to current environmental conditions. In some places, forest management has gradually transformed native diversified forests into stands converted for the greatest profit in the wood matter, thereby affecting the food availability for herbivores, among them the Eurasian beaver (Castor fiber Linnaeus, 1758). This study summarizes knowledge on non-vegetation diet selection by beavers in commercial and natural forests in the Czech Republic. A sample size of 25,723 woody plant specimens checked in 288 forest stands showed that beavers prefer willow, poplar, or hazel, but where these are less available, commercial tree species such as oak may dominate the diet and cause economic losses in forestry. Significant differences were also observed in a preference for different trunk diameters and distances from water in different types of stands. In terms of stand types, commercial monocultures are the most felled, while the probability of felling decreases with the age of stands. Based on these results and discussion, it is suggested that commercial forest stands including economically valuable woody plant species (e.g., oak, ash) could be protected through appropriate management measures, such as increasing the proportion of deciduous softwood stands along the riverbanks, which would distract the beavers from commercial woody plant species. [ABSTRACT FROM AUTHOR]

When making foraging decisions, animals evaluate the risk of being preyed upon or hunted. This applies particularly to large-bodied, long-lived species with a long evolutionary history of human persecution, such as wild boars (Sus scrofa). Wild boar populations are rapidly expanding throughout natural, agricultural, and urban areas worldwide, thus escalating human–wild boar conflicts. Most of these conflicts are associated with crop and garden damages by foraging wild boars. To study the foraging behavior of wild boars across a gradient of human risk, we evaluated the combined effects of hunting, land use type, and wild boar group size and structure on boar use of feeding devices. We installed corn-supplemented feeding devices in four land-use types and hunting combinations: urban areas with and without hunting, rural areas (namely, agricultural areas with hunting), and nature reserves without hunting. Our results show that rural areas and urban areas were the most important predictors of the wild boars' decision to eat or not and the time it took them to start eating from the moment they arrived at the feeding device (TBE—Time Before Eating). In addition, our study suggests that the TBEs of urban boars were significantly lower compared to boars from nature reserves. We further found that TBEs of urban boars were significantly lower than TBEs of boars in nature reserves. Our results suggest that the foraging behavior of wild boars varies spatially, corresponding to the different land-use types. We propose that the readiness of boars to forage in urban areas results from their habituation to human presence and lower perception of risk. [ABSTRACT FROM AUTHOR]

The behavioral and physiological mechanisms induced by high density remain mostly unknown in sea cucumbers, although it has been widely adopted to increase the space usage efficiency in aquaculture. The present study focused on investigating how high density affects fitness-related behaviors, physiology, and gene expression in the sea cucumber Apostichopus japonicus. We found that high density significantly increased crawling behavior of sea cucumbers in short-term (one week), while significantly inhibited feeding behavior in long-term (seven weeks). Foraging behavior was not significantly affected in sea cucumbers at high density. Our study found that short-term high density did not have a significant impact on the cortisol and glucose concentration in A. japonicus. There was no significant difference in serotonin (5-HT) of sea cucumbers between high and low density. Gamma-aminobutyric acid (GABA) significantly increased in sea cucumbers at high density. Thus, GABA probably plays a crucial role in regulating the behavior of A. japonicus at high density. In addition, we conducted a transcriptome analysis on intestinal tract of sea cucumbers at two different stocking densities. There were 117 differentially expressed genes (DEGs) were discovered, including 72 up-regulated DEGs and 45 down-regulated DEGs. Gene Ontology (GO) functional annotation revealed that the DEGs were significantly enriched in the processes of oxidation-reduction, dioxygenase activity, and oxidoreductase activity. Additionally, the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed a significant enrichment of DEGs in glycerolipid metabolism and PPAR signaling pathways. We highlighted LPL encoding lipoprotein esterase, which probably plays an important role in lipid metabolism in A. japonicus under high density. In conclusion, the present study clarified the behavioral and physiological reactions and further revealed the related molecular mechanisms of A. japonicus in a high-density condition. This provides valuable information into the management of the high-density aquaculture of sea cucumbers. • High density increases crawling in short-term and inhibits feeding in long-term. • GABA involved in the physiological process in A. japonicus at high density. • Antioxidant defense and lipid anabolism are regulated in A. japonicus at high density. [ABSTRACT FROM AUTHOR]

Octopuses have keen vision and are generally considered visual predators, yet octopuses predominantly forage blindly in nature, inserting their arms into crevices to search and detect hidden prey. The extent to which octopuses discriminate prey using chemo- versus mechano-tactile sensing is unknown. We developed a whole-animal behavioral assay that takes advantage of octopuses' natural searching behavior to test their ability to discriminate prey from non-prey tastes solely via contact chemoreception. This methodology eliminated vision, mechano-tactile sensing and distance chemoreception while testing the contact chemosensory discriminatory abilities of the octopus arm suckers. Extracts from two types of prey (crab, shrimp) and three types of non-prey (sea star, algae, seawater) were embedded in agarose (to control for mechano-tactile discrimination) and presented to octopuses inside an artificial rock dome; octopuses reached their arms inside to explore its contents – imitating natural prey-searching behavior. Results revealed that octopuses are capable of discriminating between potential prey items using only contact chemoreception, as measured by an increased amount of sucker contact time and arm curls when presented with prey extracts versus non-prey extracts. These results highlight the importance of contact chemoreception in the multi-modal sensing involved in a complex foraging behavior. [ABSTRACT FROM AUTHOR]

Leaf‐cutting ants forage fresh plants in the field to cultivate the symbiotic fungus in their nests. The trophallaxis rates in leaf‐cutting ants may be related to liquid foraging behavior and exchanging liquid food with other ants inside the nest. The liquid foraging and liquid food exchange in laboratory colonies of the leaf‐cutting ant Atta sexdens (L.) (Hymenoptera: Formicidae, Attini) were studied to test whether liquid food is transferred to inside‐nest workers by foragers. The foragers commonly ingested liquid when provided with a liquid source and performed different behaviors, such as self‐ and allogrooming, but without food exchange (oral trophallaxis) to the workers inside the nest. The liquid foraging was not related to food exchange with workers inside the nest. We suggest that liquid foraging meets the individual worker needs without liquid exchange among ants inside their colonies. [ABSTRACT FROM AUTHOR]

Habitat complexity describes a wide array of spatial distribution patterns of physical structures in habitats. It affects aquatic ecosystems on multiple levels from individuals (e.g., foraging behavior) to species interactions (e.g., predation, prey selection) and entire communities (e.g., biodiversity, food web structure). We present a conceptual framework to classify these effects and use it to summarize recent advances in the field. We identify three main research gaps and limitations preventing a full synthesis of the effects of habitat complexity on aquatic communities and ecosystems. Habitat complexity is often characterized using ad hoc measures, which limits cross‐experimental comparison and meta‐analytical and modeling approaches. The effects of habitat complexity on communities and ecosystems can also involve feedback loops on lower levels of organization including the habitat complexity itself. Such ecological feedbacks can influence habitat formation and amplify or mitigate the direct effects of habitat loss and simplification or habitat restoration on populations and communities, yet are surprisingly little understood. Finally, most studies examine habitat complexity on the presence‐absence scale. This limits our ability to recognize nonlinear responses across habitat complexity gradients, which occur in many contexts in aquatic habitats. Since nonlinear responses can stabilize or destabilize population and community dynamics, we call for the use of a higher resolution of habitat complexity in future studies. We conclude that currently degraded habitats offer exciting opportunities for combining restorative efforts with research that could combine multi‐level experiments and monitoring to improve our understanding of the role of habitat complexity across aquatic ecosystems. This article is categorized under:Water and Life > Nature of Freshwater EcosystemsWater and Life > Conservation, Management, and Awareness [ABSTRACT FROM AUTHOR]

The increasing interest in animal welfare and the knowledge of equine physiological and ethological needs have led to the development of different types of horses' management and housing systems. The research presented here aimed to assess the daytime activity budget of horses. Focal animal sampling was used as an observational sampling method, and the five animals were observed for a total of 9920 minutes in the paddock and inside the stall. The results showed that horses spent most of the daytime in foraging behaviors, followed by resting behaviors, and locomotion. Social behaviors (s.e. allogrooming, olfactory investigation) were rare, and the stereotypic behaviors (s.e. oral and locomotor stereotypies) occupied 2.74%±2.74% of the total time. The percentage of time spent in foraging, resting, and locomotion, reflects the activity budget observed in free-roaming feral horses. However, the rare occurrence of positive social interactions and the presence of some stereotypies could be aspects to ameliorate. This kind of housing facility could be considered a good alternative to traditional management; indeed, it might offer a better trade-off between the needs of the horse and the management goals from humans. [ABSTRACT FROM AUTHOR]

Deep diving air-breathing species by necessity must balance submergence time and level of exercise during breath-holding: a low activity level preserves oxygen stores and allows longer duration submergence whereas high activity levels consume oxygen quickly and shorten submergence time. In this study, we combined high-resolution multi sensor animal-borne tag data to investigate diving behavior and locomotion styles of the narwhal (Monodon monoceros) (n = 13, mean record length 91 h)–a deep diving Arctic species. Narwhals in this study dove down to >800 m but despite the deep diving abilities, one-third of the dives (33%) were shallow (>100 m) and short in duration (

The mere threat of predation may incite behavioral changes in prey that lead to community-wide impacts on productivity, biodiversity, and nutrient cycling. The paucity of experimental manipulations, however, has contributed to controversy over the strength of this pathway in wide-ranging vertebrate systems. We investigated whether simulated gray wolf (Canis lupus) presence can induce behaviorally-mediated trophic cascades, specifically, whether the 'fear' of wolf olfactory cues alone can change deer foraging behavior in ways that affect plants and soils. Wolves were recently removed from the Cedar Creek Ecosystem Science Reserve (Minnesota, USA), such that consumptively mediated predator effects were negligible. At 32 experimental plots, we crossed two nested treatments: wolf urine application and herbivore exclosures. We deployed camera traps to quantify how white-tailed deer (Odocoileus virginianus) adjusted their spatiotemporal habitat use, foraging, and vigilance in response to wolf cues and how these behavioral changes affected plant productivity, plant communities, and soil nutrients. Weekly applications of wolf urine significantly altered deer behavior, but deer responses did not cascade to affect plant or soil properties. Deer substantially reduced crepuscular activity at wolf-simulated sites compared to control locations. As wolves in this area predominantly hunted during mornings and evenings, this response potentially allows deer to maximize landscape use by accessing dangerous areas when temporal threat is low. Our experiment suggests that prey may be sensitive to 'dynamic' predation risk that is structured across both space and time and, consequentially, prey use of risky areas during safe times may attenuate behaviorally-mediated trophic cascades at the predator–prey interface. [ABSTRACT FROM AUTHOR]

Whether an odorant is perceived as pleasant or unpleasant (hedonic value) governs a range of crucial behaviors: foraging, escaping danger, and social interaction. Despite its importance in olfactory perception, little is known regarding how odor hedonics is represented and encoded in the brain. Here, we review recent findings describing how odorant hedonic value is represented in the first olfaction processing center, the olfactory bulb. We discuss how olfactory bulb circuits might contribute to the coding of innate and learned odorant hedonics in addition to the odorant's physicochemical properties. [ABSTRACT FROM AUTHOR]

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BACKGROUND Animal personality refers to behavioral consistency and propensity. In social insects, little is known about the interplay between colony personality and colony foraging. This study aimed to assess personality traits among colonies of the leaf‐cutting ants Acromyrmex subterraneus subterraneus and Acromyrmex subterraneus molestans and examine their behavioral consistency when provided with a toxic substrate, nasturtium leaves [Tropaeolum majus L. (Tropaeolaceae)], with potential as a management tool against these pest species. The association between colony behavioral traits and fungus garden growth was also examined, and thus the efficacy of the colony suppression. RESULTS: Behavioral variation was higher between colonies than between subspecies. Behavioral traits were correlated before and after exposure to resource‐mediated stress in both subspecies, indicating the existence of behavioral syndrome. The dimensions that contributed most to colony personality (activity, aggressiveness, and boldness) are directly related to colony resource searching and foraging. However, these dimensions diverged in their contribution before and after exposure to nasturtium. Colony activity was the major determinant of fungus garden growth, which is probably a consequence of its relationship with foraging behaviors and maintenance of the fungus garden. CONCLUSION: As the personality of a colony is unequally defined by its constituent castes, the relationship and network of interactions are determinants of foraging behaviors with relevant consequences for colony suppression using toxic foraging substrates that impair these relationships and interactions, as nasturtium leaves do. Therefore, it is plausible to say that resource‐mediated stress affects colonies personality exhibiting control potential against these species. [ABSTRACT FROM AUTHOR]

In the genus Aphaenogaster, workers use tools to transport liquid food to the colony. During this behavior, ants place or drop various kinds of debris into liquids or soft food, and then, they carry the food‐soaked tools back to the nest. According to some authors, this behavior is not "true" tool use because it represents two separate processes: a defense response to cover the dangerous liquid and a transport of food. Here, we investigated the debris dropping and retrieving behavior of the ant Aphaenogaster subterranea to establish which of the two hypotheses is more probable by conducting manipulative experiments. We tested the responses of eight colonies (a) to liquid food (honey‐water) and nonfood liquids (water) in different distances from the nest and (b) to nonthreatening liquids previously covered or presented as small droplets. We also tested whether the nutritional condition of colonies (i.e., starved or satiated) would affect the intensity and rate of debris dropping. Our results were consistent with the tool‐using behavior hypothesis. Firstly, ants clearly differentiated between honey‐water and water, and they directed more of their foraging effort toward liquids farther from the nest. Secondly, ants performed object dropping even into liquids that did not pose the danger of drowning or becoming entangled. Lastly, the nutritional condition of colonies had a significant effect on the intensity and rate of object dropping, but in the opposite direction than we expected. Our results suggest that the foraging behavior of A. subterranea is more complex than that predicted by the two‐component behavior hypothesis and deserves to be considered as "true" tool use. [ABSTRACT FROM AUTHOR]

We describe activity patterns of North American River Otters (Lontra canadensis) in relation to social group size and the presence of young. Over the course of 15 y, we collected observations of 8 River Otter behaviors from a network of citizen scientists in northern California, retaining 1692 records following a rigorous data-cleaning process. Observers were asked to indicate 1 or more of the following 8 behaviors: "diving", "swimming", "walking", "running", "digging", "turning rocks", "pursued birds", and "retreating from observer." We treated "digging", "turning rocks", and "pursued birds" as alternative foraging strategies in some comparisons. Assessment of these reports showed that families were seen diving, running, and retreating from the observers more frequently than adult groups. Likewise, adult social groups behaved differently than solitary adult otters. Propensity to retreat from humans increased with increasing group size in social otters, whereas diving behavior also increased with group size. Solitary adults employed alternative foraging strategies more than adults in social groups. Citizen observers also reported that diving and styles of foraging behavior varied among months for adult otters. Taken together, these results provide evidence that citizen-science questionnaires can be used to provide insight into the natural behaviors of species that are difficult to observe. [ABSTRACT FROM AUTHOR]

Changes in vegetation structure and species composition affect habitat use and behavior in most bird species by altering the distribution and abundance of their resources. We explore how the mating and foraging behavior of Cassin's Kingbirds (Tyrannus vociferans) varies by habitat type within a 2,450 ha urban park in Mexico City. The study site includes primarily water bodies, riparian vegetation, willow and Montezuma cypress stands, maize fields, and grasslands. We recorded kingbird behavior twice a week along 21 transects throughout 2012 and 2015. Courtship and reproductive behaviors were displayed in autumn (Sep) and early winter (Dec). Intraspecific agonistic behaviors were associated with courtship and mating events, particularly in 2015. Cassin's Kingbird generally favored open vegetation. The main foraging strategy in open habitats was flycatching but foliage gleaning became frequent when mistletoe plants produced fruits in infested willow stands. The use of mistletoe fruits, presumably a secondary diet item, coincided with the breeding season. In addition to these observations, our study is the first report of Cassin's Kingbird winter mating at low latitudes. [ABSTRACT FROM AUTHOR]

Seasonal and annual climate variations are linked to fluctuations in the abundance and distribution of resources, posing a significant challenge to animals that need to adjust their foraging behavior accordingly. Particularly during adverse conditions, and while energetically constrained when breeding, animals ideally need to be flexible in their foraging behavior. Such behavioral plasticity may separate "winners" from "losers" in light of rapid environmental changes due to climate change. Here, the foraging behavior of four sub‐Antarctic albatross species was investigated from 2015/16 to 2017/18, a period characterized by pronounced environmental variability. Over three breeding seasons on Marion Island, Prince Edward Archipelago, incubating wandering (WA, Diomedea exulans; n = 45), grey‐headed (GHA, Thalassarche chrysostoma; n = 26), sooty (SA, Phoebetria fusca; n = 23), and light‐mantled (LMSA, P. palpebrata; n = 22) albatrosses were tracked with GPS loggers. The response of birds to environmental variability was investigated by quantifying interannual changes in their foraging behavior along two axes: spatial distribution, using kernel density analysis, and foraging habitat preference, using generalized additive mixed models and Bayesian mixed models. All four species were shown to respond behaviorally to environmental variability, but with substantial differences in their foraging strategies. WA was most general in its habitat use defined by sea surface height, eddy kinetic energy, wind speed, ocean floor slope, and sea‐level anomaly, with individuals foraging in a range of habitats. In contrast, the three smaller albatrosses exploited two main foraging habitats, with habitat use varying between years. Generalist habitat use by WA and interannually variable use of habitats by GHA, SA, and LMSA would likely offer these species some resilience to predicted changes in climate such as warming seas and strengthening of westerly winds. However, future investigations need to consider other life‐history stages coupled with demographic studies, to better understand the link between behavioral plasticity and population responses. [ABSTRACT FROM AUTHOR]

The minute pirate bugs (Hemiptera: Anthocoridae) are effective biological control agents against destructive agricultural pests such as the western flower thrips, Frankliniella occidentalis Pergande (Thysanoptera: Thripidae) in agroecosystems around the world. One species, Orius insidiosus (Say), has proven effective in controlling thrips populations in fields and greenhouses, and serves as an integral component of many integrated pest management (IPM) programs. Three experiments were conducted using motion‐tracking software and dual‐choice Y‐tube bioassays to determine whether direct thrips contact and thrips cues contact induced arrestant and attractant behaviors. The experiments revealed that O. insidiosus adults exhibited behavioral changes indicative of switching from extensive to intensive foraging after direct exposure to thrips prey. Similar arresting behavior was induced by the presence of thrips tracks alone. In Y‐tube bioassays O. insidiosus showed preference towards arms containing tracks from western flower thrips larvae vs. clean arms, but only when direct contact with the tracks was made in the stem. Our data indicate that thrips deposit non‐volatile semiochemicals that are used by O. insidiosus during foraging. These compounds have the potential to aid in O. insidiosus behavior manipulation which may help in early control of thrips populations in fields and greenhouses. Further research is necessary to determine the chemical composition of these cues and how to effectively and pragmatically integrate the inducing stimuli into biocontrol programs as part of IPM strategies. [ABSTRACT FROM AUTHOR]

The dynamic environmental conditions in highly seasonal systems likely have a strong influence on how species use the landscape. Animals must balance seasonal and daily changes to landscape risk with the underlying resources provided by that landscape. One way to balance the seasonal and daily changes in the costs and benefits of a landscape is through behaviorally-explicit resource selection and temporal partitioning. Here, we test whether resource selection of coyotes (Canis latrans) in Cape Breton Highlands National Park, Nova Scotia, Canada is behaviorally-explicit and responsive to the daily and seasonal variation to presumed costs and benefits of moving on the landscape. We used GPS data and local convex hulls to estimate space use and Hidden Markov Models to estimate three types of movement behavior: encamped, foraging, and traveling. We then used integrated step-selection analysis to investigate behaviorally explicit resource selection across times of day (diurnal, crepuscular, and nocturnal) and season (snow-free and snow). We found that throughout the day and seasonally coyotes shifted foraging behavior and altered behavior and resource choices to avoid moving across what we could be a challenging landscape. These changes in behavior suggest that coyotes have a complex response to land cover, terrain, and linear corridors that are not only scale dependent but also vary by behavior, diel period, and season. By examining the resource selection across three axes (behavior, time of day, and season), we have a more nuanced understanding of how a predator balances the cost and benefits of a stochastic environment. [ABSTRACT FROM AUTHOR]

Understanding how co‐occurring species divide ecological space is a central issue in ecology. Functional traits have the potential to serve as a means for quantitatively assessing niche partitioning by different species based on their ecological attributes, such as morphology, behavior, or trophic habit. This enables testing ecological and evolutionary questions using functional traits at spatio‐temporal scales that are not feasible using traditional field methods. Both rapid evolutionary change and inter‐ and intraspecific competition, however, may limit the utility of morphological functional traits as indicators of how niches are partitioned. To address how behavior and morphology interact, we quantified foraging behavior of mixed‐species flocks of birds in the Solomon Islands to test whether behavior and morphology are correlated in these flocks. We find that foraging behavior is significantly correlated with morphological traits (p =.05), but this correlation breaks down after correcting for phylogenetic relatedness (p =.66). These results suggest that there are consistent correlations between aspects of behavior and morphology at large taxonomic scales (e.g., across genera), but the relationship between behavior and morphology depends largely on among‐clade differences and may be idiosyncratic at shallower scales (e.g., within genera). As a result, general relationships between behaviors and morphology may not be applicable when comparing close relatives. [ABSTRACT FROM AUTHOR]

The tropical estuarine guppy Poecilia vivipara was used to address fish early life stage toxicity caused by the antifouling contaminant tributyltin. Six‐day‐old P. vivipara were exposed for 7 d to control water and waterborne tributyltin at 15.8, 83.8, 716, and 818 ng tin (Sn) L–1. After exposure, swimming, feeding, growth, and eye histological endpoints were evaluated. Histopathological analysis of the retinal pigment epithelium (RPE) indicated alterations in pigment positioning at all tributyltin concentrations. A dose‐dependent increase in photoreceptor layer disorganization and iris melanin hyperpigmentation was verified, and high frequencies of RPE invaginations and iris epithelial cell atrophy were observed even at the lowest exposure concentration of 15.8 ng Sn L–1. At the highest exposure level (818 ng Sn L–1) fish also presented reductions in swimming speed, swimming resistance, daily capture of Artemia nauplii, and growth in weight of 85, 60, 33, and 56% relative to controls, respectively. This association between retinal histopathology and reduced swimming and foraging behavior can reduce recruitment to the adult population. Environ Toxicol Chem 2020;39:1953–1963. © 2020 SETAC [ABSTRACT FROM AUTHOR]

Providing individually housed dairy calves with opportunities for a greater range of natural behaviors, including foraging and grooming, has broad benefits for their behavioral development and performance. We evaluated the effects of providing hay and stationary brushes on performance and time engaged in feeding, grooming, and nonnutritive oral behaviors. Holstein calves were individually housed and assigned at 14 d of age to 1 of 4 treatments providing: a stationary brush (n = 10), chopped coastal bermudagrass hay (n = 9), both a stationary brush and chopped bermudagrass (n = 10), or no brushes nor additional feed (n = 10). Calves had ad libitum access to calf starter and water and were provided 8 L/d pasteurized waste milk fed in 2 meals via a teat bucket. Beginning at 43 d of age, calves were weaned across 10 d. Solid feed intake was measured daily, and growth parameters and cleanliness were measured weekly. Behavioral data were collected on 2 consecutive days at 25 ± 3 d, recorded continuously from video within daylight for 12 h. Provision of hay tended to increase solid feed intake and average daily gain during weaning, and calves provided a brush had improved coat cleanliness during weaning. Calves performed nonnutritive oral behavior, primarily directed toward the pen, with peaks in these abnormal behaviors around milk feeding. The duration of teat-directed nonnutritive sucking was reduced by access to either hay or a brush, compared with neither (3.2 vs. 6.8 min/12 h observation). Provision of a brush reduced pen-directed sucking (38.4 vs. 59.0 min/12 h observation), particularly at milk-feeding time, and also reduced standing time around milk feeding. Self-grooming was not affected by brush or hay access, but provision of the brush increased total time engaged in grooming behaviors (52.9 vs. 40.2 min/12 h observation). These results support benefits of accommodating natural foraging and grooming behaviors, yet reveal a high prevalence of nonnutritive oral behaviors in dairy calves. Overall, these findings underline the importance of environmental complexity in early rearing environments, and compel further consideration of behavioral needs of dairy calves to reduce the development of abnormal behaviors. [ABSTRACT FROM AUTHOR]

Innovations in foraging behavior can drive morphological diversity by opening up new ways of interacting with the environment, or limit diversity through functional constraints associated with different foraging behaviors. Several classic examples of adaptive radiations in birds show increased variation in ecologically relevant traits. However, these cases primarily focus on geographically narrow adaptive radiations, consider only morphological evolution without a biomechanical approach, or do not investigate tradeoffs with other non‐focal traits that might be affected by use of different foraging habitats. Here, we use X‐ray microcomputed tomography, biomechanical modeling, and multivariate comparative methods to explore the interplay between foraging behavior and cranial morphology in kingfishers, a global radiation of birds with variable beaks and foraging behaviors, including the archetypal plunge‐dive into water. Our results quantify covariation between the shape of the outer keratin covering (rhamphotheca) and the inner skeletal core of the beak, as well as highlight distinct patterns of morphospace occupation for different foraging behaviors and considerable rate variation among these skull regions. We anticipate these findings will have implications for inferring beak shapes in fossil taxa and inform biomimetic design of novel impact‐reducing structures. [ABSTRACT FROM AUTHOR]

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The cattle egret is globally widespread bird. Egrets are considered as an opportunistic feeder, they feed on easily obtained prey from the feeding habitat. This study reveals an analysis of seasonal diet composition with the diverse foraging behaviour used by cattle egret (Bubulcus ibis) in four different sites at Lucknow, Uttar Pradesh. The observations at the study sites results in, that cattle egrets are the highly insectivorous bird. They preferred to consume 18 orders from five phyla of prey items during the study period, which includes twelve orders of insects, three orders of Pisces, an Anura from Amphibia, Opisthopora order of Annelids and Squamata order of Reptilia. Moreover, in 13 different common feeding behaviour of herons, the 10 behaviour i.e. Walk slowly, stand and wait, walk quickly, standing fly catching, neck swaying, fly scanning and resting were observed in all habitats. Foot stirring and probing were observed in only wetlands, while Search and pecking behaviour was not found in wetlands. Rest of three i.e. Leap frog feeding, hopping and canopy feeding behaviour of herons were not present in anyoneof the feeding habitats. The descriptive study of diet and feeding behaviour is an important for the study of feeding ecology of the cattle egret. [ABSTRACT FROM AUTHOR]

The impact of multibeam echosounder (MBES) operations on marine mammals has been less studied compared to military sonars. To contribute to the growing body of MBES knowledge, echolocation clicks of foraging Cuvier's beaked whales were detected on the Southern California Antisubmarine Warfare Range (SOAR) hydrophones during two MBES surveys and assembled into foraging events called group vocal periods (GVPs). Four GVP characteristics were analyzed Before, During, and After 12 kHz MBES surveys at the SOAR in 2017 and 2019 to assess differences in foraging behavior with respect to the mapping activity. The number of GVP per hour increased During and After MBES surveys compared with Before. There were no other differences between non-MBES and MBES periods for the three other characteristics: the number of clicks per GVP, GVP duration, and click rate. These results indicate that there was not a consistent change in foraging behavior during the MBES surveys that would suggest a clear response. The animals did not leave the range nor stop foraging during MBES activity. These results are in stark contrast to those of analogous studies assessing the effect of Naval mid-frequency active sonar on beaked whale foraging, where beaked whales stopped echolocating and left the area. [ABSTRACT FROM AUTHOR]

Humans and other animals have been shown to exhibit preferences for options previously associated with greater past need. Such studies indicate that animals are sensitive to both the physical properties of choices and their own state-dependent gains at the time of learning. Because this behaviour appears to occur across divergent taxonomic groups, it most likely reflects a common way that animals learn about food. Here we study this phenomenon in the frog-eating bat, Trachops cirrhosus. This carnivorous bat hunts by eavesdropping on frog and insect mating calls and its diet is both broad and seasonally variable. As a result, these bats must learn about new sources of food and possibly the state-dependent gains associated with those sources. In this experiment we trained bats to associate two different acoustic cues (ringtones) to two identical food rewards. Each ringtone was encountered in one of two nutritional states: hungry or pre-fed. We then tested preferences between these cues under both nutritional states. We found that bats overwhelmingly preferred the ringtone associated with previous greater deprivation regardless of their condition during testing. We argue that it is most likely adaptive for frog-eating bats to place a higher value on food rewards that are obtained when internal reserves are low. • Properties of prey and state-dependent gains of predators may affect learning. • We tested whether bats' nutritional state during learning affects food preferences. • Bats preferred cues that they learned when they were in a hungry state. • Reliance on internal state as a cue to food availability is most likely adaptive. [ABSTRACT FROM AUTHOR]

In social animals, areas where the home ranges of neighboring groups overlap are often underused. The Risk Hypothesis posits that the costs of intergroup conflict create a "landscape of fear," discouraging the use of such shared areas. To test this hypothesis, we observed the behavior of white-faced capuchins (Cebus capucinus) in central vs. peripheral areas of their home ranges. If capuchins perceive areas of home range overlap as "risky," we predicted they would change activity budgets, vocalization rates, and foraging behavior in these areas. A spatially explicit behavioral comparison based on nearly 100 h of focal follows revealed that capuchins socialize less in the periphery (vs. the center) of their home range. Time spent resting, foraging, and engaging in vigilance, as well as vocalization rates, varied in consistent ways across all four study groups, but these differences did not reach statistical significance. Fruit trees near range borders (vs. the center) contained more ripe fruit, and groups spent more time in these trees, with more individuals entering to feed and consuming more fruits. However, capuchins did not alter their foraging behavior in potentially risky peripheral areas in a manner consistent with predictions of optimal foraging theory: intake rates at patch departure were not significantly lower and groups depleted trees to a greater extent along the periphery vs. in the center of their range. These results suggest that while peripheral areas are perceived as risky and this "landscape of fear" contributes to behavioral changes, they also provide resources whose value may outweigh the cost of intergroup encounters. [ABSTRACT FROM AUTHOR]

Understanding the ecological role of shelters is greatly hampered by the scarcity of long-term laboratory experiments on the trade-off between fitness benefits and costs. This lack probably leads to an underestimation of the negative and/or positive effects on behaviors and growth of marine invertebrates in benthic ecosystems. Although our previous study revealed a significant effect on fitness-related traits of Glyptocidaris crenularis after 31 months, the present study extended it and investigated fitness benefits and/or costs of long-term sheltering on sea urchins to over 7 years. The present long-term study suggests that the previously reported reduction in feeding rate probably resulted from a reduction in reflexive feeding motions (Aristotle’s lantern reflex) rather than changes in foraging behavior. Actively seeking sheltering behavior was negatively impacted in individuals with continuous access to shelters. However, covering and righting behaviors did not differ in sheltered sea urchins, indicating that these behaviors are maintained to escape from adverse environments regardless of shelter. Body size of sea urchins in the group with shelters was significantly lower than those without shelters after 7 years. Weights of gonads and gut were not significantly different after 7 years despite previous observations of differences after ~2.5 years. The present study provides valuable information on the trade-off between fitness benefits and costs to sea urchins residing in shelters. However, the present study is only a laboratory investigation for one urchin species (G. crenularis) which does not consider the complexity of natural environments. Field studies should be carried out with G. crenularis and other sea urchin species, before a more universal conclusion can be drawn. [ABSTRACT FROM AUTHOR]

Traffic noise is known to negatively affect many wildlife species by interfering with foraging behavior. Frogs often lay their eggs in roadside ditches because they are predator-free, but it is possible that traffic noise could reduce the survival and fitness of tadpoles, creating an ecological trap. In a series of lab experiments, we tested whether traffic noise has a negative impact on tadpole feeding behavior, whether this is mediated by changes in tadpole activity, and whether there is any impact on tadpole growth rate or metamorphosis. Traffic noise exposure significantly reduced the amount of food consumed by Cuban Treefrog (Osteopilus septentrionalis) tadpoles. Traffic noise exposure also increased the activity level of both Southern Toad (Anaxyrus terrestris) and Cuban Treefrog tadpoles, which could possibly make them more noticeable to predators in the wild. However, these behavioral changes were not associated with changes in growth rate or timing of metamorphosis. We caution, however, that this study aimed to isolate the specific impact of traffic noise, and did not investigate other road effects that may be damaging to tadpoles. [ABSTRACT FROM AUTHOR]

In the wild, giraffes live complex social lives exhibiting fission-fusion social systems. They have sophisticated communication which likely forms a crucial component regulating subgroup dynamics. They spend a large part of their day browsing and traveling over large distances. In captivity, lack of continuous browsing opportunities and limited space can lead to various abnormal and stereotypic behaviours. These stereotypic behaviours can have cascading detrimental health consequences. A behavioural analysis of stereotypic behaviours in giraffes under human care was conducted to evaluate sources of variation within a population and provide management recommendations. The aim of this investigation was threefold: 1. to examine current behaviour of giraffes in Zoological Garden Alipore, Kolkata to advise on their enhanced management; 2. to highlight any behavioural abnormalities and recommend enrichment mechanisms; and 3. to compare the observed stereotypic behaviours with behaviour described in other zoological institutions and in the wild to provide a focal trajectory in the development of guidelines. Four individuals (two adult males, one adult female, and one male calf) were observed outdoors for seven days, three times a day for 30 minutes by instantaneous scan sampling method. During the observation period, the giraffe exhibited oral stereotypy more than any other behaviour recorded, though this was recorded disproportionally between individuals. The giraffe spent a larger amount of time exhibiting oral stereotypy compared to feeding/foraging activities. The study suggests incorporating diet and feeding strategies with provision of natural browse as well as offering enrichment methods to increase the foraging time using various time-engaged feeding devices to mitigate the observed abnormal stereotypic behaviour. Additionally, recommendations are made for expanding the size of the open enclosure to meet guidelines by the Central Zoo Authority, as a minimum. [ABSTRACT FROM AUTHOR]

The red imported fire ant, Solenopsis invicta Buren, is a serious agricultural and public health pest in its introduced range. Several natural products have been tested to replace synthetic insecticides for the novel, economically feasible and environmentally friendly control of this pest. No information is available on the toxicity of vitamins to red imported fire ants. This study examined the effects of l-ascorbic acid (vitamin C) on the survival and behavior of red imported fire ants. In a toxicity assay, l-ascorbic acid (l-AA, vitamin C) appeared to be the most toxic vitamin to S. invicta and caused significantly higher mortality of S. invicta than the control and other tested vitamins. Concentration- and exposure time-dependent mortality of ants was observed after feeding on different concentrations of l-AA. S. invicta equally preferred l-AA and sucrose solution and rapidly transferred l-AA by workers. Significant adverse effects on the necrophoric, recruiting and foraging behavior of this pest insect were observed after feeding on l-AA. The walking speed of l-AA-fed ants was significantly reduced; however, we observed no significant difference in mortality of ants during group aggression assays. When we examined the presence of l-AA in the hemolymph and excretion, unlike in the normal control, more l-AA was observed in the hemolymph of the workers that ingested 0.05/0.1 g/ml of l-AA solution after 48 h. However, there was no significant difference in the concentration of l-AA in the excretion. This study demonstrated that l-AA has negative effects on S. invicta and can be used as baits to provide a highly effective and environmentally sustainable method to control red imported fire ants. [ABSTRACT FROM AUTHOR]

[Display omitted] • Solenopsis invicta virus 3 infection causes mortality in Solenopsis invicta. • Egg care by worker ants was unaffected by SINV-3 infection status. • The study clarifies SINV-3 pathogenesis in its host, S. invicta. • Neglect of brood by worker ants is not a factor in all-stage mortality by SINV-3. Solenopsis invicta virus 3 (SINV-3) has been shown to cause significant mortality among all stages of its host, Solenopsis invicta. One impact of the virus is alteration of worker ant foraging behavior, which results in colony starvation and collapse over time. Additionally, it has been hypothesized that SINV-3 infection of S. invicta may disrupt worker ant brood care behavior. To investigate this possibility, various combinations of SINV-3-infected and -uninfected adult (worker) and immature (brood) stages were placed together and monitored using the response variables, mortality, egg hatch, and virus load. While significant differences in percent cumulative S. invicta worker ant mortality among six combinations of SINV-3-infected and -uninfected stages were observed, no significant differences in percent cumulative mortality of S. invicta larvae or pupae were observed. No significant differences in egg hatch were observed among SINV-3-uninfected, SINV-3-infected (colony-treated and queen-treated), and starved colonies. Eggs hatched normally in 10–12 days for all treatments indicating that egg care by worker ants was unaffected by SINV-3 infection status. The study further clarifies SINV-3 pathogenesis in its host, S. invicta. Larval mortality in SINV-3-infected colonies does not appear to be caused by worker ant neglect. S. invicta brood under the care of SINV-3-infected worker ants did not exhibit higher mortality rates compared with those tended by SINV-3-uninfected worker ants. [ABSTRACT FROM AUTHOR]

Chemical signals play a central role in mediating insect feeding and reproductive behavior, and serve as the primary drivers of the insect-plant interactions. The detection of chemical signals, particularly host plant volatiles, relies heavily on the insect's complex olfactory system. The Bemisia tabaci cryptic species complex is a group of globally important whitefly pests of agricultural and ornamental crops that have a wide range of host plants, but the molecular mechanism of their host plant recognition is not yet clear. In this study, the odorant coreceptor gene of the Whitefly MEAM1 cryptic species (BtOrco) was cloned. The coding sequence of BtOrco was 1413 bp in length, with seven transmembrane structural domains, and it was expressed primarily in the heads of both male and female adult whiteflies, rather than in other tissues. Knockdown of BtOrco using transgenic plant-mediated RNAi technology significantly inhibited the foraging behavior of whiteflies. This inhibition was manifested as a reduced percentage of whiteflies responding to the host plant and a prolonged foraging period. Moreover, there was a substantial suppression of egg-laying activity among adult female whiteflies. These results indicate that BtOrco has the potential to be used as a target for the design of novel active compounds for the development of environmentally friendly whitefly control strategies. [Display omitted] • The BtOrco gene was highly expressed in the heads of whitefly adults. • BtOrco silencing significantly suppressed the foraging behavior of whiteflies. • After BtOrco silencing, egg-laying by adult female whiteflies was significantly suppressed. [ABSTRACT FROM AUTHOR]

I present 2 noteworthy foraging observations of a Lesser Yellow-headed Vulture (Cathartes burrovianus) and a Turkey Vulture (C. aura) in Crooked Tree Wildlife Sanctuary and Cockscomb Basin Wildlife Sanctuary, Belize, respectively. I observed a Lesser Yellow-headed Vulture successfully capture a live fish from the water and a Turkey Vulture feeding on feces of neotropical otter (Lontra longicaudis) along a river. To my knowledge, these observations represent novel reports for each species, and contribute to the understanding of the breadth of foraging behavior of cathartid vultures. [ABSTRACT FROM AUTHOR]

Backround: Commensal microbes can promote survival and growth of developing insects, and have important fitness implications in adulthood. Insect larvae can acquire commensal microbes through two main routes: by vertical acquisition from maternal deposition of microbes on the eggshells and by horizontal acquisition from the environment where the larvae develop. To date, however, little is known about how microbes acquired through these different routes interact to shape insect development. In the present study, we investigated how vertically and horizontally acquired microbiota influence larval foraging behaviour, development time to pupation and pupal production in the Queensland fruit fly ('Qfly'), Bactrocera tryoni. Results: Both vertically and horizontally acquired microbiota were required to maximise pupal production in Qfly. Moreover, larvae exposed to both vertically and horizontally acquired microbiota pupated sooner than those exposed to no microbiota, or only to horizontally acquired microbiota. Larval foraging behaviour was also influenced by both vertically and horizontally acquired microbiota. Larvae from treatments exposed to neither vertically nor horizontally acquired microbiota spent more time overall on foraging patches than did larvae of other treatments, and most notably had greater preference for diets with extreme protein or sugar compositions. Conclusion: The integrity of the microbiota early in life is important for larval foraging behaviour, development time to pupation, and pupal production in Qflies. These findings highlight the complexity of microbial relations in this species, and provide insights to the importance of exposure to microbial communities during laboratory- or mass-rearing of tephritid fruit flies. [ABSTRACT FROM AUTHOR]

Antipredator behavior is known to have a strong effect on prey population dynamics. While there have been many studies of antipredator behavior in population dynamic models, none have examined how antipredator behavior interacts with predator foraging mode. To examine this process, we incorporated predator and prey velocities into a simple tritrophic food chain. In this model, antipredator behavior allows prey to respond to predators by slowing their velocity in response to predator density. Prey can slow their velocity to hide from predators, but this in turn reduces their ability to consume resources, creating a trade-off between hiding and foraging. We examined the effects of both fast-moving "mobile" predators and slow-moving "sit-and-wait" predators on equilibrium prey density and amplitude of predator-prey cycles. We found that antipredator behavior was ineffective against mobile predators, but it was very effective against sit-and-wait predators. Antipredator responses to sit-and-wait predators reduced top-down control and allowed prey density to increase with increased carrying capacity. Furthermore, antipredator responses to sit-and-wait predators eliminated population cycles within the community, whereas antipredator behavior had no effect on population cycles within mobile predator communities. Therefore, our model demonstrates predator foraging mode must be taken into account when examining predator-prey cycles. We discuss the potential implications of this model for invasive species and for trophic cascades. [ABSTRACT FROM AUTHOR]

Cooperative breeding often evolved in harsh and arid habitats characterized by high levels of environmental uncertainty. Most forms of cooperative behavior have energetic costs and previous studies have shown that the contributions of individuals to alloparental provisioning are conditional on their food intake. However, the effect of naturally occurring, extreme environmental conditions on the persistence of costly forms of cooperative behaviors and their coordination by communication remain unknown. Here, we show that in meerkats (Suricata suricatta) the probability to act as sentinel, a cooperative vigilance behavior, was the same for typically occurring dry and wet conditions, but significantly reduced during a drought condition with almost no rain, especially in young individuals, members of small groups and groups with pups. The duration an individual stayed on sentinel guard, however, was most reduced during dry conditions. Besides reductions in sentinel behavior, the vocal coordination of foraging meerkats differed when comparing drought and wet conditions. Individuals responded more strongly to playbacks of sentinel "all-clear" calls and close calls, resulting in less vigilance and more foraging behavior during the drought condition. We conclude that while meerkats are adapted to commonly occurring dry periods with low rainfall, the extreme drought period with almost no rain, led to a decrease of the frequency of costly forms of cooperative behaviors in favor of behaviors that maximize direct fitness benefits and also affected the vocal coordination among group members. [ABSTRACT FROM AUTHOR]

Interspecific competition for limited resources can drive ecological specialization and trait expression. Organisms released from intense competition may exploit a broader range of resources, but if reunited with stronger competitors, survivorship may depend on foraging behaviors that reduce competition. We compared the host selection behavior of the parasitoid Cotesia glomerata from two North American populations that differ in their association with Cotesia rubecula, a superior competitor. Both parasitoids originate from Europe and attack the imported cabbageworm (a.k.a. small cabbage white) Pieris rapae, but C. glomerata was introduced into North America almost a century before C. rubecula. After re-association in North America, C. rubecula has displaced C. glomerata in several regions, but not in other regions. Host selection was measured in female C. glomerata from Maryland (MD) where it coexists with C. rubecula, and in conspecifics from Colorado (CO) where C. rubecula is absent. Unparasitized and C. rubecula-parasitized P. rapae hosts were used in choice tests to examine whether C. glomerata host selection behavior differed based on the population's association history with C. rubecula. We found that C. glomerata from MD had a higher likelihood of avoiding hosts parasitized by C. rubecula (and thus avoiding competition) than did wasps from CO. The ability of C. glomerata to avoid hosts parasitized by C. rubecula may facilitate coexistence in MD; whereas, the lack of discrimination in CO populations of C. glomerata naïve to C. rubecula could contribute to the displacement of C. glomerata were C. rubecula to enter the same habitat. [ABSTRACT FROM AUTHOR]

Most studies on the effects of neonicotinoid insecticides on neural processes of honey bees are based on behaviours performed by adult bees exposed as adults. It is unclear how the developing brains of honey bee larvae are affected by sublethal doses of neonicotinoid insecticides when measuring neural processes through behavioural performance in adult bees. In this study, larvae were exposed to three sublethal doses of clothianidin and evaluated 25–36 days later for hygienic and foraging behaviours as adult bees. The medium and highest sublethal doses of clothianidin significantly reduced hygienic and foraging activity. The greatest effects were on the proportion of adult bees foraging and carrying pollen. These results show that exposure of larvae to clothianidin results in negative effects extending into the adulthood of bees, possibly compromising the colony's fitness by impairing pathogen control mechanisms and by reducing pollen collection. [ABSTRACT FROM AUTHOR]