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Several animal species use tools for foraging; however, very few manufacture and/or modify those tools. Humpback whales, which manufacture bubble-net tools while foraging, are among these rare species. Using animal-borne tag and unoccupied aerial system technologies, we examine bubble-nets manufactured by solitary humpback whales (Megaptera novaeangliae) in Southeast Alaska while feeding on krill. We demonstrate that the nets consist of internally tangential rings and suggest that whales actively control the number of rings in a net, net size and depth and the horizontal spacing between neighbouring bubbles. We argue that whales regulate these net structural elements to increase per-lunge prey intake by, on average, sevenfold. We measured breath rate and swimming and lunge kinematics to show that the resulting increase in prey density does not increase energetic expenditure. Our results provide a novel insight into how bubble-net tools manufactured by solitary foraging humpback whales act to increase foraging efficiency.

Biologging studies rely on the assumption that equipped animal behaviours are representative of the ones displayed by unequipped individuals. Identifying any tagging effects is therefore necessary to correctly interpret recorded data from equipped animals. The majority of seabird studies report an absence of tag effects using broad metrics such as breeding success or foraging trip duration. However, animals may compensate for tag attachment through increased effort or behavioural responses. We compared foraging trip and dive characteristics of 42 breeding Manx shearwaters (Puffinus puffinus) equipped with a range of biologging tags representing 0.9–3.7% body mass. There was no evidence that increasing tag weight affected foraging trip duration, but individuals equipped with heavier tags travelled shorter distances and at slower speed as well as spending more time in Area Restricted Search behaviour. The number of dives performed per hour of foraging trip was not affected by increasing tag weight, but individuals with the heaviest tags conducted shorter and shallower dives with slower ascent rates than those equipped with lighter tags. Additionally, birds equipped with the heaviest tags increased resting time between dives, suggesting a need to recover from a greater physiological cost of diving when equipped. Our study is one of the few that describe acute tagging impacts on seabird diving behaviour and foraging effort, suggesting that deployments should be kept as short as possible to limit cumulative impacts. [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]

The Chilean clingfish Gobiesox marmoratus Jenyns (Gobiesocidae) is a common carnivorous fish inhabiting the rocky intertidal pools along the Chilean coast. In spite of its wide-ranging distribution, basic knowledge about this species is scarce and as a consequence important aspects of its biology such as dietary composition, dietary selectivity and trophic behaviour have received little attention. The goals of this work were to assess quantitatively the dietary composition of this species, its trophic selectivity, assimilation rate of its prey and to experimentally analysed the role of the prey energy value, pre-digestive and post-digestive limitations in the dietary selection of this species. The diet of this species is mainly based on invertebrates, particularly amphipods, crabs and limpets as the most important food items. In laboratory, crabs and amphipods were the most preferred and consumed items over limpets and snails. Our results show that the amphipod is the prey item that provides to G. marmoratus with greater energy per unit of time of manipulation, which would explain its preference in the laboratory experiments and suggests that G. marmoratus feeds according to the net energy gain of their prey, supporting energy maximization, an underlying assumption of foraging theory. [ABSTRACT FROM AUTHOR]

Female Weddell seals (Leptonychotes weddellii) display a mixed capital-income breeding strategy, losing up to 40% of their body mass between birthing and weaning their pups. How and when they regain energy stores, however, remains to be fully explored. To better understand the foraging by lactating Weddell seals, we fitted time-depth recorders and head-mounted cameras on 26 seals in Erebus Bay, Ross Sea, for ~ 5 days in November and December 2018 and 2019. We aimed to (1) identify prey species and foraging depth and (2) investigate relationships between seal physiology and demographics and probability of foraging. We recorded 2782 dives, 903 of which were > 50 m, maximum depth was 449.3 m and maximum duration was 31.1 min. Pup age likely contributes to the probability of a lactating Weddell seal foraging (Est. = 1.21 (SD = 0.61), z = 1.97, p = 0.0484). Among 846 prey encounters, the most frequent prey items were crustaceans (46.2%) and Antarctic silverfish (Pleuragramma antarcticum, 19.0%); two encounters were observed with juvenile Antarctic toothfish (Dissostichus mawsoni, 0.2%). We identified substantial variability in foraging behaviour, individually and between locations, and found that lactating seals target many species and some may specialise on certain prey groups.

The current study investigated avian diversity correspondence with the potential threats to their habitat in and around Rudrasagar Lake. This study designed extensive field surveys at sixteen sites following distance point counting and fixed transect methods for birds' quantification. Currently, total 56 avian species were recorded, of which 55.35% species primarily inhabit waterbody peripheral terrestrial (WPT) zone, while 28.57% prefer to forage in swampy zones around the edge of the water body (EWB). Only 16.07% of bird species were recorded in open water bodies (IOW). The study also stratified 85.74% of the bird species as residents and 14.28% as migrants. Network mapping also showed that omnivores were the most prevalent (41.07%) while insectivores (16.07%) and herbivores (10.07%) were less common due to their specific diets. Shannon-Weiner (H'), Simpson (Ds) and Pielou's (J') indices indicated higher species diversity and relatively even distribution among the WPT community. Bird diversity was observed lowest at Rajghat which experienced the highest degree of anthropogenic disturbances for traditional tourism and recreational activities. Surface area reduction for encroachment posed a substantial threat to habitat health for IOW birds. Near-threatened and vulnerable species like Oriental darter, Common pochard and Painted stork recorded in 2002 are conspicuously absent from recent surveys. Declining avian population and local extinctions related to wetland degradation is considered a serious threat. Proposed management plan implied the requirement to conserve this enclave in accordance to increase the avian population and habitat sustainability. Therefore, this scholarly work drew immediate attention to develop management strategies for avian species conservation. [ABSTRACT FROM AUTHOR]

Abstract Evidence‐based conservation can benefit substantially from multiple knowledge sources and different knowledge systems. While traditional ecological knowledge (TEK) and collaborative research are increasingly acknowledged, detailed cross‐knowledge system reviews are scarce and their methodology underdeveloped. We have two objectives: to prepare such a review and to discuss the benefits and challenges of such reviews. We review pig keeping in forests and marshes, a historically widespread but nowadays almost extinct practice in Europe, but one with high potential for organic farming, conservation and restoration. We focus on what, when and how free‐ranging pigs forage in the wild. We review five knowledge sources: living and archived TEK, pig and wild boar scientific literature, and the authors' observations of foraging. Unexpectedly, given the amount of available information, archived TEK differed considerably from living TEK of svinjars (Serbian: traditional pig keepers), and scientific knowledge on pig and boar foraging from TEK. Svinjars deeply understood the consumption and avoidance behaviour of pigs towards 98 and 56 plant taxa, and 42 and 17 animal taxa, respectively. Our review showed that pigs are gourmet omnivores, optimizing and switching between foraging on earthworms, acorns, grasses and corn. Discrepancies between knowledge sources were rare, for example on the consumption of woody roots, earthworms, mushrooms and snakes/lizards. Sources were also complementary, filling each other's knowledge gaps. Topics where the cross‐knowledge system review was most fruitful were acorn foraging, browsing, earthworm and mushroom consumption. Differences in the contributions of the knowledge sources to the enriched picture resulted from the diverging interests and methodologies of the knowledge generators. We identified and discussed both the benefits (different approaches of knowledge generation; expanded time scales; complementarity; novel cause–effect explanations; identification of knowledge gaps; and biases) and the challenges (how to identify relevant publications and knowledgeable TEK holders; how to collate knowledge and verify its reliability; and how to conduct a culturally respectful synthesis) of cross‐knowledge system reviewing. Synthesis and applications. Cross‐knowledge system reviews help overcome limitations in ecological understanding and may provide a shared understanding among collaborating partners, build trust and foster acceptance of each other's knowledge as legitimate. Read the free Plain Language Summary for this article on the Journal blog.

The variations in floral biology of the eight tested apple cultivars were found to affect the abundance and foraging behaviour of the insect visitors. Apis cerana (3.23 bees/m2/min) was the recorded pre-dominant insect visitor followed by Episyrphus balteatus (2.96 insect visitors/m2/min), Apis mellifera (2.89 bees), Ischiodon scutellaris (2.70 insect visitors) and Eristalis tenax (2.57 insect visitors). The cultivars Gale Gala and Jeromine attracted maximum insect visitors due to more flower spread and higher nectar productivity. The average number of flowers visited by bees per minute was more in Gale Gala, Auvil Early Fuji and Red Cap Valtod due to favourable floral characters and higher nectar sugar concentration. Irrespective of the cultivars, A. mellifera visited comparatively more apple flowers (9.23 flowers/min) and spent less time on a single flower (9.52 s/flower) as compared to A. cerana (8.21 flowers/min, 10.77 s), E. tenax (5.37 flowers/min, 23.51 s) and E. balteatus (5.57 flowers/min, 24.37 s). The top worker A. mellifera (59.52%) outnumbered the side workers (40.48%). The maximum loose pollen grains were observed in E. tenax (7914.27) followed by A. mellifera (5209.80), A. cerana (3165.73) and E. balteatus (670.07). Therefore, it was concluded from the present study that floral biology along with nectar production affected the abundance and foraging behaviour of the insect visitors in the apple cultivars. [ABSTRACT FROM AUTHOR]

Evidence‐based conservation can benefit substantially from multiple knowledge sources and different knowledge systems. While traditional ecological knowledge (TEK) and collaborative research are increasingly acknowledged, detailed cross‐knowledge system reviews are scarce and their methodology underdeveloped. We have two objectives: to prepare such a review and to discuss the benefits and challenges of such reviews.We review pig keeping in forests and marshes, a historically widespread but nowadays almost extinct practice in Europe, but one with high potential for organic farming, conservation and restoration. We focus on what, when and how free‐ranging pigs forage in the wild. We review five knowledge sources: living and archived TEK, pig and wild boar scientific literature, and the authors' observations of foraging.Unexpectedly, given the amount of available information, archived TEK differed considerably from living TEK of svinjars (Serbian: traditional pig keepers), and scientific knowledge on pig and boar foraging from TEK. Svinjars deeply understood the consumption and avoidance behaviour of pigs towards 98 and 56 plant taxa, and 42 and 17 animal taxa, respectively. Our review showed that pigs are gourmet omnivores, optimizing and switching between foraging on earthworms, acorns, grasses and corn. Discrepancies between knowledge sources were rare, for example on the consumption of woody roots, earthworms, mushrooms and snakes/lizards. Sources were also complementary, filling each other's knowledge gaps.Topics where the cross‐knowledge system review was most fruitful were acorn foraging, browsing, earthworm and mushroom consumption. Differences in the contributions of the knowledge sources to the enriched picture resulted from the diverging interests and methodologies of the knowledge generators.We identified and discussed both the benefits (different approaches of knowledge generation; expanded time scales; complementarity; novel cause–effect explanations; identification of knowledge gaps; and biases) and the challenges (how to identify relevant publications and knowledgeable TEK holders; how to collate knowledge and verify its reliability; and how to conduct a culturally respectful synthesis) of cross‐knowledge system reviewing.Synthesis and applications. Cross‐knowledge system reviews help overcome limitations in ecological understanding and may provide a shared understanding among collaborating partners, build trust and foster acceptance of each other's knowledge as legitimate. Read the free Plain Language Summary for this article on the Journal blog. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

ABSTRACT In stream ecosystems, invertebrates are a principal source of prey for many fishes, but their abundance as a food source depends on the predator's ability to exploit them in time and space. Although salmonid fishes are commonly thought of as daytime drift‐feeding predators of invertebrates in streams, they exhibit great flexibility in foraging behaviour and may also consume prey from the benthos and at night. Char species, (Salvelinus sp.), in particular, may be better adapted to forage under low light conditions due to greater scotopic sensitivity than other salmonids. In this study, we used in situ or in place videography to quantify the foraging behaviour of bull trout (Salvelinus confluentus) and determine when and where they capture prey. We found that bull trout were primarily daytime predators of invertebrates drifting in the water column, and that they rarely captured prey from the benthos or foraged at night. We did observe size‐related differences and seasonal declines in foraging rate from summer to fall months. A modelled estimate of energy intake indicates that daytime drift‐feeding by small size classes of bull trout was above that needed for a maximum daily ration under a range of assumptions about prey size and prey retention rates. Energy intake rates for larger fish were more dependent on assumptions of preferred prey size and prey retention rates. Our data indicate that daytime measures of invertebrate drift abundance and size are the most inclusive measure of food abundance for stream‐dwelling bull trout. [ABSTRACT FROM AUTHOR]

Female Weddell seals (Leptonychotes weddellii) display a mixed capital-income breeding strategy, losing up to 40% of their body mass between birthing and weaning their pups. How and when they regain energy stores, however, remains to be fully explored. To better understand the foraging by lactating Weddell seals, we fitted time-depth recorders and head-mounted cameras on 26 seals in Erebus Bay, Ross Sea, for ~ 5 days in November and December 2018 and 2019. We aimed to (1) identify prey species and foraging depth and (2) investigate relationships between seal physiology and demographics and probability of foraging. We recorded 2782 dives, 903 of which were > 50 m, maximum depth was 449.3 m and maximum duration was 31.1 min. Pup age likely contributes to the probability of a lactating Weddell seal foraging (Est. = 1.21 (SD = 0.61), z = 1.97, p = 0.0484). Among 846 prey encounters, the most frequent prey items were crustaceans (46.2%) and Antarctic silverfish (Pleuragramma antarcticum, 19.0%); two encounters were observed with juvenile Antarctic toothfish (Dissostichus mawsoni, 0.2%). We identified substantial variability in foraging behaviour, individually and between locations, and found that lactating seals target many species and some may specialise on certain prey groups. [ABSTRACT FROM AUTHOR]

The eusocial "paper wasp" Polistes dominula is an invasive species that has successfully established worldwide. In the present study, we investigate the foraging behaviour of P. dominula wasps when revisiting previously gathered resources. We recorded the number of learning flights and food manipulation efficiency performed by a single target wasp during several consecutive collecting visits. Additionally, we analysed P. dominula relocating behaviour when dealing with changes in food position. We assessed whether wasps choose the previously visited dish containing food or opt for a novel baited dish placed 60 cm away. Then, we trained wasps to collect food either once or three times and compared the time taken to find the novel food position when it was displaced 60 cm away. This is the first study to demonstrate relocating behaviour in P. dominula in which wasps rapidly learned to return to certain food sites. A significant reduction in learning flights after only one collecting visit was observed. Likewise, wasps learned to manipulate the resource spending less time after each experience. Moreover, when two food sources were offered, after just one visit, the majority of wasps collected the resource from the previously rewarded dish. Furthermore, when food was displaced, foragers found the new food location more rapidly after one visit than after three consecutive collecting experiences. Our findings contribute to the understanding of P. dominula behavioural plasticity while collecting food sources in anthropized environments, which highlight the importance of considering such learning experiences. [ABSTRACT FROM AUTHOR]

Pesticides and the lack of floral resources are key drivers of insect decline in agricultural areas. Both land‐use stressors can have a variety of synergistic and sublethal effects on pollinators, affecting their health and foraging behaviour. Pollinating insects include species with vastly different life histories, giving them potentially different vulnerability and resilience to stressors. However, most research has generally focused on bees. Here, we contrast synergistic effects of nutritional stress and pesticide use on social bumblebees and solitary hoverflies.We experimentally tested the effects of the neonicotinoid acetamiprid and low‐quality food on health traits of Bombus terrestris workers and Episyrphus balteatus adults (ovarian development, body size and colony development or survival). The foraging behaviour of treated pollinators was recorded in a semi‐field setup and, for B. terrestris, we measured the pollen amount on the body surface and the pollen deposited on stigmata after a single floral visit.Both stressors affected bumblebee health. Additionally, insecticide‐treated workers showed increased flower handling times and flight durations, while low‐quality food reduced the amount of pollen on the surface of bumblebees and the pollen deposited on stigmata. Syrphids were mostly affected by low‐quality food, which decreased their survival probability and changed their foraging behaviour. Furthermore, we found an interactive effect between the two stressors, reducing E. balteatus ovary development.Synthesis and applications. Insecticide and food stress affected fitness traits of both bumblebees and syrphid flies, possibly reducing pollinator populations under natural conditions. Especially for bumblebees, long‐term exposure led to a reduction in the provision of pollination services, both by changing their behaviour and reducing pollen transfer. We found differences between the two pollinator groups, showing that results gained from single groups like bees should not be extrapolated to all pollinators. Interactive effects indicate potential buffering effects of high‐quality food against other stressors and highlight the importance of considering synergies between multiple stressors in risk assessments. This further emphasizes the relevance of floral resources such as wild flower strips in agricultural areas to conserve pollinators and pollination services. [ABSTRACT FROM AUTHOR]

Mallophora ruficauda is a dipteran ectoparasitoid and insect predator native to South America, that as an adult feeds mainly on foraging honeybees. Under suitable conditions, population outbreaks can detrimentally impact apiculture and plant pollination. In turn during its larval stages, it serves as a parasitoid of scarab beetle larvae that can affect a variety of crops. This review offers an updated insight into the ecology and behaviour of M. ruficauda, presenting new information on how it selects its prey and hosts, a process distinctively carried out by both adults and larvae. By studying this species as a predator and parasitoid, our work sheds light on intricate ecological interactions, paving the way for strategies centered on early detection, containment, and management. The implications of these findings are crucial for developing effective and eco-friendly approaches to mitigate the impact of M. ruficauda on apiculture while balancing its ecological importance. [ABSTRACT FROM AUTHOR]

As more and more species are in decline, understanding the various aspects underlying their population dynamics is crucial to optimise conservation efforts. Hereto, we studied the diet composition and reproductive performance of Gull-billed Terns forming the last breeding population in Central Europe by analysing population-level data collected between 2011 and 2022 as part of a conservation program. We show that the main prey types vary among breeding stages and across years. When observed foraging for themselves, Gull-billed Terns were mainly found to eat insects, whereas crabs and worms were the main prey items used for courtship feeding and chick provisioning. The proportion of prey of terrestrial origin used for courtship feeding increased over the study period, whereas no such change was observed in prey used for self-feeding or chick provisioning. Clutch and egg size also increased over the study period but were not correlated with the proportion of terrestrial prey used in courtship. Fledging success did not change over time and was not correlated with variation in chick diet. These results confirm that the Gull-billed Terns in this population are generalist feeders and suggest that their breeding success is not currently threatened by a lack of, or changes in, specific prey types. The shift towards more terrestrial prey in part of their diet may, however, indicate changes in the aquatic ecosystem, which should be further assessed, together with other potential risks for these threatened birds, such as inbreeding and pollution. [ABSTRACT FROM AUTHOR]

Pollination stands out as the paramount ecosystem service facilitated by insect pollinators, providing benefits to over three quarters of the world's major crops. The conservation and effective management of honeybees constitute integral components for ensuring the sustainable productivity of cross-pollinated crops. The present study aimed to document the potential pollinators of lucerne in the Bundelkhand region in India, which is known for its subtropical climatic conditions. Further, the foraging behaviour, including foraging rate and speed, was meticulously documented. A total of 13 insect species from seven families across three insect orders were observed visiting lucerne flowers. Hymenopterans comprised the majority of the floral visitors (73.48%), followed by Lepidoptera (26.51%) during the study period. Among them, Apis dorsata (Hymenoptera: Apidae) emerged as the most predominant floral visitor, exhibiting peak activity at 12:00 h with a density of 7.85 bees/m2/10 min. Surprisingly, among the major floral visitors, A. florea has the highest mean foraging rate (number of flowers visited/minute/forager), i.e., 11.56, 11.59 and 10.79 bees/flowers/minute during the initial flowering stage, peak flowering stage and late flowering stage, respectively. However, the foraging speed (time spent by the forager on each flower) was longest in A. dorsata , i.e., 5.05, 3.78 and 5.41 s/flower during initial, peak and late flowering stages, respectively. The findings emphasize the importance of enhancing honeybee activity to boost lucerne seed yield. Further, the outcomes of the study can be leveraged to optimize honeybee colony management, scheduling field operations such as pesticide application and weeding during periods of minimal honeybee activity. [ABSTRACT FROM AUTHOR]

Plant–hummingbird interactions are considered a classic example of coevolution, a process in which mutually dependent species influence each other's evolution. Plants depend on hummingbirds for pollination, whereas hummingbirds rely on nectar for food. As a step towards understanding coevolution, this review focuses on the macroevolutionary consequences of plant–hummingbird interactions, a relatively underexplored area in the current literature. We synthesize prior studies, illustrating the origins and dynamics of hummingbird pollination across different angiosperm clades previously pollinated by insects (mostly bees), bats, and passerine birds. In some cases, the crown age of hummingbirds pre‐dates the plants they pollinate. In other cases, plant groups transitioned to hummingbird pollination early in the establishment of this bird group in the Americas, with the build‐up of both diversities coinciding temporally, and hence suggesting co‐diversification. Determining what triggers shifts to and away from hummingbird pollination remains a major open challenge. The impact of hummingbirds on plant diversification is complex, with many tropical plant lineages experiencing increased diversification after acquiring flowers that attract hummingbirds, and others experiencing no change or even a decrease in diversification rates. This mixed evidence suggests that other extrinsic or intrinsic factors, such as local climate and isolation, are important covariables driving the diversification of plants adapted to hummingbird pollination. To guide future studies, we discuss the mechanisms and contexts under which hummingbirds, as a clade and as individual species (e.g. traits, foraging behaviour, degree of specialization), could influence plant evolution. We conclude by commenting on how macroevolutionary signals of the mutualism could relate to coevolution, highlighting the unbalanced focus on the plant side of the interaction, and advocating for the use of species‐level interaction data in macroevolutionary studies. [ABSTRACT FROM AUTHOR]

Body size, bill length and shape determine foraging techniques, habitat selection and diet among shorebirds. In this study, water depth preferences of different shorebirds with different bill sizes in various habitats including mudflats, mangroves at Kadalundi‐Vallikkunnu Community Reserve (KVCR) (19 shorebird species) and adjacent agroecosystems at Vazhakkad (12 species) were studied between 2017 and 2020. The bill length of the shorebirds was significantly and positively associated with the average water depth, where shorebirds were observed to forage. Shorebirds with shorter bill lengths preferred shallow waters and those with longer bills preferred deep waters for their foraging activities. Habitat type also had a significant effect on the shorebird occurrence. Eurasian Curlews in both mangroves and mudflats were observed in areas with a higher water depth compared to other species. This is due to the fact that shorebirds tend to specialise in feeding habitats or in prey items to reduce intraspecific competition and distribute themselves in space and time in accordance with the availability of their resources. The occurrence of some species in agroecosystems is attributed to the reduced food availability, habitat quality and other disturbances for shorebirds on tidal flats, which are critical for sustaining migratory phenology. The differences in bill morphology are crucial in determining diet, water depth, niche preferences and segregation. Morphological characters and hydrological rhythms determine specialisation in diet and habitat preference in shorebirds. [ABSTRACT FROM AUTHOR]

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Animals construct and inhabit nests that can exhibit dramatic intra- and interspecific variation due to differences in behaviour, the biotic and abiotic environment, and evolutionary history. In ants, variation in nest architecture reflects both differences in ecology and in the collective behaviour of the colonies that live in the nests. Each component of the nest (such as depth, and the number, size and connectivity of chambers) reflects selective pressures for different functions, or structural constraints that are imposed by the environment or evolutionary history. To determine potential drivers of nest structure variation in subterranean nests, we performed a meta-analysis of measures of published ant nests to compare different structural elements within and across species. We complemented this survey with 42 nest casts of two closely related species. We quantified nest features that can potentially impact ant foraging behaviour and examined whether phylogeny or foraging strategy are better explanatory variables for the variation we observed. We found that foraging strategy better explained nest features than evolutionary history. Our work reveals the importance of ecology in shaping nest structure and provides an important foundation for future investigations into the selective pressures that have shaped ant nest architecture. This article is part of the theme issue 'The evolutionary ecology of nests: a cross-taxon approach'.

Some taxa of wading birds can locate buried prey by detecting vibratory cues in their foraging substrates while probe‐foraging, using a sensory modality called 'remote‐touch'. As more saturated substrates transmit vibrations better, we predict that these birds can detect prey in wetter substrates more easily. We used sensory assays to test whether substrate water content affects the remote‐touch foraging success rate of Hadeda ibises, Bostrychia hagedash. The birds were more successful at locating prey using vibratory cues than when relying on random direct contact with the beak alone. Their remote‐touch foraging success rate was positively affected by increasing water contents of the soil, but water content had no effect on their direct contact foraging success (indicating this is not an artefact of ease of probing). This may partially explain the link between the range expansion of this species in southern Africa and increased soil irrigation, as it is easier for the birds to detect prey in wetter substrates. Thus, it is likely that the distribution of other remote‐touch foraging birds is affected by substrate water content, and as many of these species are endangered and rely on sensitive wetland habitats, it is vital to understand their sensory requirements for foraging. [ABSTRACT FROM AUTHOR]

Recent evidence suggests that individuals differ in foraging tactics and this variation is often linked to an individual's behavioural type (BT). Yet, while foraging typically comprises a series of search and handling steps, empirical investigations have rarely considered BT‐dependent effects across multiple stages of the foraging process, particularly in natural settings.In our long‐term sleepy lizard (Tiliqua rugosa) study system, individuals exhibit behavioural consistency in boldness (measured as an individual's willingness to approach a novel food item in the presence of a threat) and aggressiveness (measured as an individual's response to an 'attack' by a conspecific dummy). These BTs are only weakly correlated and have previously been shown to have interactive effects on lizard space use and movement, suggesting that they could also affect lizard foraging performance, particularly in their search behaviour for food.To investigate how lizards' BTs affect their foraging process in the wild, we supplemented food in 123 patches across a 120‐ha study site with three food abundance treatments (high, low and no‐food controls). Patches were replenished twice a week over the species' entire spring activity season and feeding behaviours were quantified with camera traps at these patches. We tracked lizards using GPS to determine their home range (HR) size and repeatedly assayed their aggressiveness and boldness in designated assays.We hypothesised that bolder lizards would be more efficient foragers while aggressive ones would be less attentive to the quality of foraging patches. We found an interactive BT effect on overall foraging performance. Individuals that were both bold and aggressive ate the highest number of food items from the foraging array. Further dissection of the foraging process showed that aggressive lizards in general ate the fewest food items in part because they visited foraging patches less regularly, and because they discriminated less between high and low‐quality patches when revisiting them. Bolder lizards, in contrast, ate more tomatoes because they visited foraging patches more regularly, and ate a higher proportion of the available tomatoes at patches during visits.Our study demonstrates that BTs can interact to affect different search and handling components of the foraging process, leading to within‐population variation in foraging success. Given that individual differences in foraging and movement will influence social and ecological interactions, our results highlight the potential role of BT's in shaping individual fitness strategies and population dynamics. [ABSTRACT FROM AUTHOR]

Effective seabird conservation requires understanding their marine spatial ecology. Tracking can reveal details of their foraging ecology and habitat use, as well as the suitability of marine protected areas for at-sea conservation, but results are often regionally specific. Here we characterised the foraging behaviour of tropical breeding brown boobies Sula leucogaster in the Chagos Archipelago, Western Indian Ocean, and tested habitat requirements. GPS tracking of thirteen individuals from two colonies, located 142 km apart on the same atoll (Great Chagos Bank), showed similar foraging effort and habitat preferences despite differences in season and breeding stage. Brown boobies from both tracked populations foraged close to the colony along the atoll shelf edge, avoiding deep oceanic areas and shallow waters of the Great Chagos Bank atoll, but within the Chagos Archipelago Marine Protected Area. Sea-level height anomaly and sea surface temperature were important foraging predictors at both sites, although birds experienced distinct environmental conditions between colonies. These results suggest that while brown boobies have colony-specific at-sea foraging areas, similarities in habitat drivers of distribution and foraging behaviour can inform predictions of distributions at other colonies within the archipelago, with important benefits for at-sea conservation efforts. [ABSTRACT FROM AUTHOR]

This study examined how habitat and resource conditions influence the foraging behaviour and ecology of the Pale (Pallid) Flycatcher Agricola pallidus and Marico Flycatcher Bradornis mariquensis, two perch-and-pounce insectivores that swoop on prey from elevated perches. These species were studied in the early 1980s at the Nylsvley Nature Reserve in Limpopo Province, South Africa, where Marico Flycatchers occupied fine-leafed, spinescent Vachellia (Acacia) tortilis-dominated woodland, while Pale Flycatchers were confined to Burkea africana-dominated mesophyll woodland. These two woodland types correspond to two contrasting savanna types across Africa more broadly: arid-eutrophic, fine-leafed savannas and mesic/moist-dystrophic, broad-leafed woodlands. Their juxtaposition at the Nylsvley Reserve provided an opportunity to explore the factors affecting the habitat preferences and foraging behaviour of these two species. Acacia woodlands had higher invertebrate abundance, at least on the ground, and lower groundcover than Burkea woodlands in both seasons, although the difference was less during the dry season. Throughout the year, Marico Flycatchers consistently foraged at a faster rate, pouncing more frequently and more successfully on prey than did Pale Flycatchers. They also spent less time searching from each perch and gave up sooner if they found nothing. The average time difference between successful and unsuccessful searches was only a few seconds for both species, however. Presumably because they occupied a less productive woodland, Pale Flycatchers had considerably larger home ranges and occurred at lower densities overall, and so experienced fewer intraspecific and interspecific interactions. In contrast, Marico Flycatchers faced more competition both intra- and interspecifically, especially in the dry season when prey was scarce; they lost most of their conflicts, all with larger birds. Habitat separation between these two flycatcher species is apparently maintained by the differences in habitat structure, resource availability and occasional interspecific interactions, in which Marico Flycatchers dominated Pale Flycatchers. [ABSTRACT FROM AUTHOR]

Despite a clear preference of the Eurasian Three-toed Woodpecker Picoides tridactylus for spruce trees as foraging sites by both males and females, some studies showed intersexual resource partitioning that allows competition for food to be minimized. The objective of the study was to characterize foraging sites of the Three-toed Woodpecker in the primeval stands of the Białowieża National Park (BNP, Poland) in relation to sex. Although the woodpeckers foraged on seven tree species, both males and females foraged predominantly on spruce (83% and 90% of the observations, respectively). Selection indices showed a significant preference for dead spruce trees for both sexes and additionally for live spruce trees in the case of females. Spruce trees where woodpeckers foraged were twice as thick as those available, regardless of whether they were dead or alive. The only feature differentiating the feeding sites of males and females was the diameter of the part of the tree at foraging locations. This suggests that there is some niche partitioning between the sexes of the Three-toed Woodpecker in primeval stands of the BNP. Our research clearly showed that even in the very rich environment of the BNP, abounding in various forms of dead wood, large dead spruce trees are crucial for the Eurasian Three-toed Woodpecker. [ABSTRACT FROM AUTHOR]

Australian warblers (Acanthizidae) and pardalotes (Pardalotidae) are abundant keystone species in Australia. Collectively they help regulate arthropod populations and dampen outbreaks of phytophagous insects. Their conservation in the face of habitat degradation and climate change is essential for the retention of healthy forest ecosystems and biodiversity. Information at the level of detail required for effective conservation management is missing for most Australian birds, including warblers and pardalotes. It is unlikely the data needed for the conservation of these species will be obtained in time to prevent further losses of avian biodiversity. However, it is important to try. This paper describes the foraging behaviour during spring of seven species of Australian warblers and pardalotes (small insectivores) in the Great Western Woodland, Western Australia and expands our knowledge of the ecology of these birds. As reported for small insectivores elsewhere in the world, species differed in prey-attack behaviours, foraging substrates, plant species used for foraging, foraging heights, and habitats. These data are used to explain why, without changes in how Australia approaches the preservation of biodiversity, abundant birds, such as Australian warblers and pardalotes will decline towards extinction. [ABSTRACT FROM AUTHOR]

Porina (Wiseana spp.) are endemic to New Zealand with some species adapting to exotic pastures, where they cause significant damage. Porina larvae cannot be identified to species level in the field so the relative impact of each porina species is not known. Greater knowledge of foraging behaviour by different porina species will help to determine species-specific impacts. The nocturnal foraging behaviours of W. cervinata and W. copularis larvae were investigated in the laboratory using videos recorded under infrared conditions. Foraging behaviours were characterised, and videos analysed using BORIS software found species differences in the number of burrows constructed and in foraging choices. Behavioural sequences were similar for both porina species, with W. cervinata larvae foraging exclusively on white clover while W. copularis foraged on white clover and ryegrass. W. cervinata larvae constructed one horizontal burrow whereas W. copularis constructed 2–3 horizontal burrows to reach their food plants. By constructing several horizontal burrows, W. copularis larvae have access to more plants without exposing themselves above ground to adverse weather conditions or predators. This may be an advantageous strategy for W. copularis larvae, particularly at high population densities when food becomes scarce, and may increase the degree of pasture damage caused by this species relative to other Wiseana spp. Porina management should target the most damaging species within the complex and this study provides further evidence that W. copularis is more likely to cause pasture damage. [ABSTRACT FROM AUTHOR]

Brain form (i.e., brain size and morphology) has been linked to variation in foraging behaviour among species of fishes in lakes and oceans, such as larger brains associated with fish foraging higher in the food chain. However, much less is known about these relationships across habitats, or in stream fishes. Therefore, we explore relationships between foraging behaviour and brain form in the omnivorous creek chub (Semotilus atromaculatus) across different streams of Southwest Ontario, Canada. We assessed foraging behaviour variables (i.e., trophic position, proportion of terrestrial energy in diet and foraging flexibility on aquatic and terrestrial resources) against brain form (i.e., relative brain size and the proportional size of the cerebellum, hypothalamus, olfactory bulbs, optic tectum, and telencephalon). Principal component analysis was used to extract covariation patterns among the size of brain regions. We found that creek chub brain size is positively associated with trophic position and proportion of terrestrial energy in diet, but not foraging flexibility. The first principal component, explaining 91% of size covariation among brain regions, was also positively associated with trophic position but not with proportion of terrestrial energy in diet suggesting that brain regions outside of those measured contribute to the association between brain size and proportion of terrestrial energy in diet. Our results suggest that a relationship between brain size and trophic position may be common among fishes, and that foraging on resources from the terrestrial energetic pathway in streams may present a novel, yet to be characterized cognitive challenge for fish. [ABSTRACT FROM AUTHOR]

We present a comprehensive dataset comprising head- and eye-centred video recordings from human participants performing a search task in a variety of Virtual Reality (VR) environments. Using a VR motion platform, participants navigated these environments freely while their eye movements and positional data were captured and stored in CSV format. The dataset spans six distinct environments, including one specifically for calibrating the motion platform, and provides a cumulative playtime of over 10 h for both head- and eye-centred perspectives.The data collection was conducted in naturalistic VR settings, where participants collected virtual coins scattered across diverse landscapes such as grassy fields, dense forests, and an abandoned urban area, each characterized by unique ecological features. This structured and detailed dataset offers substantial reuse potential, particularly for machine learning applications.The richness of the dataset makes it an ideal resource for training models on various tasks, including the prediction and analysis of visual search behaviour, eye movement and navigation strategies within VR environments. Researchers can leverage this extensive dataset to develop and refine algorithms requiring comprehensive and annotated video and positional data. By providing a well-organized and detailed dataset, it serves as an invaluable resource for advancing machine learning research in VR and fostering the development of innovative VR technologies.

Flower colour is a crucial factor influencing pollinator-plant interactions. Lantana camara L., a popular ornamental plant, attracts various butterfly species. The present study was conducted in Serampore, Hooghly, West Bengal, India, spanning a period of one year from June 2022 to May 2023. This study investigates the preferences of some butterfly species for flowers of a certain colour and the choice of Lantana camara flowers as nectar sources. L. camara is known for its vibrant and diverse colour variations, making it an ideal candidate for attracting various pollinators. Through field observations and controlled experiments, we aimed to identify if certain butterfly species exhibit distinct colour preferences when foraging on Lantana blooms. Our preliminary findings suggest that different butterfly species display varying degrees of colour selectivity, with some showing a preference for warm colour within the L. camara spectrum. These initial insights provide a foundation for further research into the intricate relationship between butterfly species and floral coloration. Understanding the nuanced preferences of butterflies for L. camara flowers can contribute to the development of targeted conservation and gardening practices aimed at supporting specific butterfly populations. This study offers a valuable starting point for future investigations into the broader implications of floral colour preferences in pollinator ecology.

Abstract: Emerging infectious diseases in wildlife can threaten vulnerable host populations. Actions targeting habitat improvements to aid population resilience and recovery may be beneficial long‐term strategies, yet testing the efficacy of such strategies before major conservation investments are made can be challenging. The disease white‐nose syndrome (WNS) has caused severe declines in several species of North American hibernating bats. We tested a novel conservation approach targeted at improving foraging conditions near bat hibernacula by experimentally manipulating insect density in the pre‐hibernation fattening period and spring emergence recovery period. We measured foraging (feeding buzzes) and echolocation activity of little brown bats Myotis lucifugus at ultraviolet (UV) light lures to determine behavioural response to augmented foraging conditions and characterized insect availability at UV light lures. In the fall, bat foraging activity was three times greater (95% CI: 1.5–5.8; p = 0.002) when UV lights were on, but there was no statistical support for differences in echolocation activity response when our experimental design alternated between nights with lights on and off. In the spring, we allowed UV light lures to run consistently each night and compared with a control location in similar habitat. Bat foraging activity was 8.5 times greater (95% CI: 4.5–16.0; p

Weddell seals (Leptonychotes weddellii) are important predators in the Southern Ocean and are among the best-studied pinnipeds on Earth, yet much still needs to be learned about their year-round movements and foraging behaviour. Using biologgers, we tagged 62 post-moult Weddell seals in McMurdo Sound and vicinity between 2010 and 2012. Generalized additive mixed models were used to (i) explain and predict the probability of seal presence and foraging behaviour from eight environmental variables, and (ii) examine foraging behaviour in relation to dive metrics. Foraging probability was highest in winter and lowest in summer, and foraging occurred mostly in the water column or just above the bottom; across all seasons, seals preferentially exploited the shallow banks and deeper troughs of the Ross Sea, the latter providing a pathway for Circumpolar Deep Water to flow onto the shelf. In addition, the probability of Weddell seal occurrence and foraging increased with increasing bathymetric slope and where water depth was typically less than 600 m. Although the probability of occurrence was higher closer to the shelf break, foraging was higher in areas closer to shore and over banks. This study highlights the importance of overwinter foraging for recouping body mass lost during the previous summer.

Abstract Although pesticide-free techniques have been developed in agriculture, pesticides are still routinely used against weeds, pests, and pathogens worldwide. These agrochemicals pollute the environment and can negatively impact human health, biodiversity and ecosystem services. Acetamiprid, an approved neonicotinoid pesticide in the EU, may exert sub-lethal effects on pollinators and other organisms. However, our knowledge on the scope and severity of such effects is still incomplete. Our experiments focused on the effects of the insecticide formulation Mospilan (active ingredient: 20% acetamiprid) on the peripheral olfactory detection of a synthetic floral blend and foraging behaviour of buff-tailed bumblebee (Bombus terrestris) workers. We found that the applied treatment did not affect the antennal detection of the floral blend; however, it induced alterations in their foraging behaviour. Pesticide-treated individuals started foraging later, and the probability of finding the floral blend was lower than that of the control bumblebees. However, exposed bumblebees found the scent source faster than the controls. These results suggest that acetamiprid-containing Mospilan may disrupt the activity and orientation of foraging bumblebees. We hypothesize that the observed effects of pesticide exposure on foraging behaviour could be mediated through neurophysiological and endocrine mechanisms. We propose that future investigations should clarify whether such sub-lethal effects can affect pollinators’ population dynamics and their ecosystem services.

The term pyric herbivory was first introduced in 2009, describing how fire shapes herbivory as burned areas attract herbivores and, simultaneously, herbivory shapes fuel load and fire behaviour. Pyric herbivory results in a mosaic of patches with varying levels of herbivory and grazing intensity fire intensity and frequency. The importance of pyric herbivory for ecosystem heterogeneity and biodiversity has been described for North American, Australian and African systems, but the concept remains largely untested in a European context.We introduced fire and herbivory in a full‐factorial experiment in a temperate European wood‐pasture system to test whether pyric herbivory operates in ways comparable to grassy systems elsewhere in the world. Using camera traps, we observed the behaviour of cattle in burned subplots (49 m2) compared with unburned subplots. We measured grass height and the proportion of the subplot that burned as variables affecting cattle preference and to assess how grazing affects fire behaviour. We also examined the effect on plant species and life‐form composition after six seasons of treatment.Cattle spent more time grazing in burned than in unburned subplots in the most productive paddock, where a larger proportion of the subplot burned. The proportion of a subplot that burned was positively related to pre‐fire grass height. Moreover, both grass height and the proportion of subplot burned declined in the burned subplots during the 6‐year study period and fire and cattle grazing altered the relative cover of graminoids and shrubs (Rubus spp.), with more graminoids in grazed and/or burned subplots and more shrubs in ungrazed subplots at the end of the study.Synthesis and applications. In our temperate European wood pasture, fire and (cattle) grazing interacted in ways comparable to pyric herbivory in grassy ecosystems elsewhere in the world, especially in the most productive paddock. Fire attracted grazing, with cattle grazing longer on subplots that burned more fully. Grazing also affected fire, where over the course of our experiment cattle grazing reduced grass height and the proportion of a subplot that burned. We suggest that pyric herbivory is an interesting management method to further explore in the European context to address the loss of biodiversity in open ecosystems, particularly in more productive sites. [ABSTRACT FROM AUTHOR]

Several species of birds deliberately drop hard food items, such as walnuts and molluscs, from high places to break the shell and eat the content. Although the carrion crow Corvus corone preys on the introduced apple snail Pomacea canaliculata by directly breaking the shells with their beaks in paddy fields in Japan, snails living in ponds are too large and hard for crows to directly break the shells. We found that carrion crows dropped apple snails in and around dried ponds in winter in Marugame, Kagawa, Japan, and conducted detailed observations on their predation behaviour. The crows dropped the snails onto various substrates in and around Hachijo Pond, and the release point was higher when the substrate was wet mud than when it was concrete, rock, or grass. As carrion crows rarely prey on other freshwater snails in Japan, this foraging behaviour has likely developed since the introduction of apple snails in the 1980s. The intense predation by the crows likely reduced the snail density in this reservoir pond. [ABSTRACT FROM AUTHOR]

Avian gut microbial communities are complex and play a fundamental role in regulating biological functions within an individual. Although it is well established that diet can influence the structure and composition of the gut microbiota, foraging behaviour may also play a critical, yet unexplored role in shaping the composition, dynamics, and adaptive potential of avian gut microbiota. In this review, we examine the potential influence of coprophagic foraging behaviour on the establishment and adaptability of wild avian gut microbiomes. Coprophagy involves the ingestion of faeces, sourced from either self (autocoprophagy), conspecific animals (allocoprophagy), or heterospecific animals. Much like faecal transplant therapy, coprophagy may (i) support the establishment of the gut microbiota of young precocial species, (ii) directly and indirectly provide nutritional and energetic requirements, and (iii) represent a mechanism by which birds can rapidly adapt the microbiota to changing environments and diets. However, in certain contexts, coprophagy may also pose risks to wild birds, and their microbiomes, through increased exposure to chemical pollutants, pathogenic microbes, and antibiotic‐resistant microbes, with deleterious effects on host health and performance. Given the potentially far‐reaching consequences of coprophagy for avian microbiomes, and the dearth of literature directly investigating these links, we have developed a predictive framework for directing future research to understand better when and why wild birds engage in distinct types of coprophagy, and the consequences of this foraging behaviour. There is a need for comprehensive investigation into the influence of coprophagy on avian gut microbiotas and its effects on host health and performance throughout ontogeny and across a range of environmental perturbations. Future behavioural studies combined with metagenomic approaches are needed to provide insights into the function of this poorly understood behaviour. [ABSTRACT FROM AUTHOR]