Age Area Research Articles

Interactions between anchovy fisheries and Peruvian boobies revealed by bird-borne cameras and movement loggers

Fisheries threaten marine predator populations through bycatch and competition for the same resources, but may also provide feeding opportunities. Understanding benefits and mitigating impacts, therefore, requires a detailed understanding of fishery interactions. The Humboldt Current system supports the world’s largest single-species fishery (Peruvian anchoveta Engraulis ringens), along with abundant marine predators dependent on these forage fish, including seabirds. We combined bird-borne video cameras and GPS-acceleration-dive loggers to quantify the foraging behaviour of chick-rearing Peruvian boobies Sula variegata around Isla Macabi, Peru, in December 2020 and May 2021. Videos revealed that 18% of 77 Peruvian booby foraging trips included feeding at actively fishing purse seine vessels, diving in and around the nets. Most vessel interactions were close to the colony, and we found no difference in foraging effort (e.g. trip duration) between trips with and without vessel interactions. We recorded fishing effort in the foraging range of the colony using remotely sensed data from the vessel monitoring system accessed via Global Fishing Watch, finding more frequent interactions and catch depredation when fishing effort was high near the colony. We found no evidence that birds expended additional energy (e.g. dynamic body acceleration) or travelled to different locations to reach vessels. We emphasise the value of combining high-resolution movement and video loggers with remotely sensed fisheries data to monitor seabird-fishery interactions in detail, rather than just spatio-temporal overlap, and assess the potential for competition and bycatch. Threatened seabird populations may benefit from no-take zones or reduced fishing effort in core foraging areas of colonies.

Where’s the best supermarket deal? Female Southern Rockhopper Penguins (Eudyptes chrysocome) show variable foraging areas during the guard stage at Isla de los Estados, Argentina

Understanding the spatial distribution of seabirds contributes to comprehending their ecological requirements and dispersion patterns. We studied the at-sea distribution of female Southern Rockhopper Penguins (Eudyptes chrysocome (J.R. Forster, 1781)) at Isla de los Estados colony during the early chick-rearing period. We used a clustering analysis approach to identify different groups according to the foraging trip (tracking and diving data from GPS and temperature and depth data loggers) and diet (δ15N composition on blood samples) characteristics. Foraging trips differed in duration, location, and dive depths explored. Females in clusters 1 and 3 traveled longer distances and in opposite directions (36.3 ± 21.3 and 40.3 ± 14.0 km, respectively). Females in cluster 2 fed closer to the colony (16.8 ± 7.8 km). Dives occurred in pelagic habitats. Higher δ15N values suggested a greater proportion of fish (e.g., the Fuegian sprat, Sprattus fuegensis (Jenyns, 1842)) consumption in the northern foraging areas (cluster 1). The variability observed in the spatial distribution suggests flexibility in the foraging behavior of Southern Rockhopper Penguins and availability of adequate foraging areas within the colony range during the early chick-rearing period, both important features for Southern Rockhopper Penguin population. These results contribute to understanding the use of the Southern Ocean by marine mesopredators and top predators and to the marine spatial planning in the area.

Satellite Tracking of Post-nesting Green Sea Turtles (Chelonia mydas) From Ras Baridi, Red Sea

Identifying migratory pathways and linking nesting sites to foraging areas is essential for effective conservation management of migratory species, such as marine turtles. Post-nesting marine turtles disperse from their nesting sites to multiple foraging areas located from a few to hundreds of kilometers away. Over a six-year period 16 female green turtles (Chelonia mydas) were equipped with satellite transmitters between October and December of five nesting seasons to determine their migratory routes from their nesting area at five contiguous beaches at Ras Baridi, Saudi Arabia, to their foraging areas. All foraging areas for these turtles were located in shallow coastal areas or in shallow areas around offshore islands within the Red Sea basin. The majority (n = 12) migrated through the shallow (<200 m) water along the coastal margin to reach foraging areas located to the North (n = 4) and South (n = 12) of the nesting site. Four turtles crossed the deep trough of the Red Sea during their journeys. Ten of the 16 turtles migrated to foraging areas within the territorial waters of Saudi Arabia. The other six turtles migrated to foraging areas in Egypt (n = 4) and Eritrea (n = 2). These 16 turtles traveled between 130 and 1749 km from their nesting site to foraging areas located in the northern, middle and southern parts of the Red Sea. Because these turtles utilized foraging areas in at least three countries (Saudi Arabia, Egypt, and Eritrea) and one passed through the territorial waters of Sudan, conservation and management of green turtles in the Red Sea requires multinational cooperation to address anthropogenic threats in the region.

Flight distance and foraging of Tetragonisca fiebrigi (Apidae: Meliponini) in response to different concentrations of sugar in food resources and abiotic factors

Social bees rely on food resources collected from flowers while foraging to guarantee the survival of their offspring. Pollen and nectar are the most important of these resources for protein and energy sources. This study analyzed the maximum flight distance of Tetragonisca fiebrigi (Shwarz, 1938) and the influence of sugar concentration of food resources and abiotic factors on visiting rates. Experiments were carried out in the Botanical Garden in South Brazil. The workers were training to collect sugar syrup from artificial feeders (water and sugar, 1:1) to which an aromatic essence (peach) had been added to attract the bees. It was found that workers reduced the number of visits as the distance to food sources increased. The experiments with feeders indicated that the maximum flight distance of T. fiebrigi workers from the four colonies analyzed reached 600 m. Additionally, 95% of visits to the feeder were within 350 m (colony C) or 400 m (colonies A, B, and D) of the hives. The number of worker visits could be significantly explained for all colonies (p < 0.05) by a relationship with flight distance, with explanatory power ranging from 65% to 89%. Regarding accumulated foraging activity, 75% was concentrated in distances up to 200 m from the colonies and the recruitment increased in higher sugar concentrations. Knowledge about achievable flight distances and effective foraging areas enables the planning of conservation measures, such as ensuring the availability of food resources in the landscape.

Little Ringed Plover Charadrius dubius chicks swim to expand their foraging area with encouragement from their parents: an observation

Little Ringed Plover Charadrius dubius chicks swim to expand their foraging area with encouragement from their parents: an observation

The Diet of a Roosting Population of Asian Glossy Starling Aplonis panayensis in Jelebu, Negeri Sembilan, Malaysia

Communal roosting by urban birds, such as crows, mynas, and starlings, can be a public nuisance due to excessive noise and fouling of the surroundings with droppings. Food availability within proximity to the roosting area is one of the key factors influencing roosting site preference and fidelity. The diets of roosting mynas and crows have been well-studied, yet little is known about the diet of the Asian glossy starling (AGS), Aplonis panayensis. This study focused on assessing the diet of roosting AGS and food resource availability around the roosting area. The AGS diet was assessed through microscopic analysis of stomach contents and droppings. The diet mainly consisted of fruits (76%) with a minor component of animal materials, i.e. ants, snails, and beetle larvae. Intact seeds found in the samples were identified using DNA barcoding. Seven out of the nine plant species detected were new records for the AGS diet. The most common fruit found in the samples was Trema orientalis, which grows extensively along roadsides within foraging areas of AGS. The availability of fruits of different fast-growing pioneer species around the roosting site ensured a continuous supply of food to the birds. Animal materials, which were consumed by chance during foraging, supplemented the fruit in the bird’s diet. Hence, the birds’ preference for the roosting site may have been influenced by the availability of various food resources around it.

Phosphoproteomic basis of neuroplasticity in the antennal lobes influences the olfactory differences between A. mellifera and A. cerana honeybees

The honeybee species A. mellifera and A. cerana have evolved substantial differences in olfactory-driven behaviors and in peripheral olfactory systems. Knowledge of the central nervous system regulating these olfaction differences is limited, however. We compared the phosphoproteome of the antennal lobes (ALs, the primary olfactory neuropil) of A. mellifera and A. cerana, and identified a total of 2812 phosphopeptides carrying 2971 phosphosites from 1265 phosphoproteins. Of these, 76% of the phosphoproteins were shared by both species, which were mainly presynapse and cytoskeleton components, and were involved in signal transduction and neurotransmitter secretion. This finding indicates the fundamental role of protein phosphorylation in regulating signal transduction in the ALs. The mTOR signaling pathway, the phagosome pathway, and the autophagy pathway, which are important in protein metabolism, were enriched, suggesting glomeruli plasticity and olfactory processing are intensively modulated by phosphorylation via these pathways. Compared with A. mellifera, 107 phosphoproteins associated with protein metabolism and transport were uniquely expressed in A. cerana, indicating the protein synthesis-dependent synaptic plasticity is enhanced in A. cerana to facilitate the processing of more complex floral odor clues in mountain foraging areas. This finding is further supported by the significantly upregulated key phosphoproteins of the mTOR signaling pathway in A. cerana ALs. These results provide insights into the phosphoproteomic basis of neuroplasticity that is coupled with the divergent evolution of bees in different environments. SignificanceTo adapt to their own ecological niche, the two major honeybee species, A. mellifera and A. cerana, have developed significant difference in olfactory-driven behaviors, but our understanding of the underlying regulation of the central nervous system is still limitate. Here we performed the first comprehensive phosphoproteomic comparison of antennal lobes (Als) between A. mellifera and A. cerena. A large proportion of the identified phosphosites and phosphoproteins were shared between the two species to serve as a core network in the regulation of signal transduction and glomeruli plasticity of ALs. However, compared with A. mellifera, 107 phosphoproteins associated with protein metabolism and transport were uniquely identified in A. cerana ALs, and also several key phosphoproteins in mTOR signaling pathway were found upregulated in A. cerana. These findings indicate protein phosphorylation enhanced the protein synthesis-dependent synaptic plasticity in A. cerana to facilitate the processing of more complex floral odor clues in mountain foraging areas. Our data provide a valuable insight into phosphoproteome-driven cerebral regulation of honeybee olfactory behaviors, which is potentially useful for further neurobiological investigation in both honeybees and other insects.

Feeding at the front line: interannual variation in the use of glacier fronts by foraging black-legged kittiwakes

Tidewater glacier fronts can represent important foraging areas for Arctic predators. Their ecological importance is likely to change in a warmer Arctic. Their profitability and use by consumers are expected to vary in time, but the underlying mechanisms driving such variation remain poorly known. The subglacial plume, originating from meltwater discharge, is responsible for the entrainment and transport of zooplankton to the surface, making them more readily available for surface-feeding seabirds. Both discharge and zooplankton abundance are known to fluctuate in time and are thus expected to modulate the foraging profitability of glacier fronts. This study tested the predictions that annual use of glacier fronts by black-legged kittiwakes Rissa tridactyla is positively related to the average glacier discharge and prey biomass in the fjord. To do this, we combined a multiyear dataset of environmental drivers and GPS tracks of birds in Kongsfjorden, Svalbard. Our results confirmed the interannual variation in the use of glacier fronts by kittiwakes; however, contrary to our predictions, these variations were negatively correlated to both glacier discharge and zooplankton abundance. These apparent negative relationships likely reflect non-linear effects and complex interactions between local and regional environmental factors that affect the relative profitability of glacier fronts as foraging areas. Despite their high spatial predictability, glacier fronts may not offer consistent foraging opportunities for marine predators over time.

Urban nature at the fingertips: Investigating wild food foraging to enable nature interactions of urban dwellers

Meaningful human–nature interactions can counteract the extinction of experience and positively influence people’s nature relatedness, health and wellbeing. In this study, we explored urban wild food foraging to understand how best to enable human-nature interactions in cities by means of foraging. Using a structured questionnaire, a total of 458 residents of Vienna, Austria were surveyed. Sixty-four percent of visitors of public urban green spaces previously foraged for wild food species, whereas foraging frequencies were related to the targeted plant species and their life forms. People who foraged more frequently had greater nature relatedness, more childhood foraging experiences and lived on the outskirts of the city, but their socio-demographic backgrounds were heterogeneous. Social acceptance and lack of access to wild foods were perceived to be barriers. To promote nature relatedness through urban foraging, the legal framework, access to low-contamination foraging areas, availability of wild foods and social acceptance need to be improved.

Different individual-level responses of great black-backed gulls (Larus marinus) to shifting local prey availability.

To grow, survive and reproduce under anthropogenic-induced changes, individuals must respond quickly and favourably to the surrounding environment. A species that feeds on a wide variety of prey types (i.e. generalist diet) may be comprised of generalist individuals, specialist individuals that feed on different prey types, or a combination of the two. If individuals within a population respond differently to an environmental change, population-level responses may not be detectable. By tracking foraging movements of great black-backed gulls (Larus marinus), a generalist species, we compared group-level and individual-level responses to an increase in prey biomass (capelin; Mallotus villosus) during the breeding season in coastal Newfoundland, Canada. As hypothesized, shifts in prey availability resulted in significantly different individual responses in foraging behaviour and space use, which was not detectable when data from individuals were combined. Some individuals maintained similar foraging areas, foraging trip characteristics (e.g., trip length, duration) and habitat use with increased capelin availability, while others shifted foraging areas and habitats resulting in either increased or decreased trip characteristics. We show that individual specialization can be non-contextual in some gulls, whereby these individuals continuously use the same feeding strategy despite significant change in prey availability conditions. Findings also indicate high response diversity among individuals to shifting prey conditions that a population- or group-level study would not have detected, emphasizing the importance of examining individual-level strategies for future diet and foraging studies on generalist species.

Characterization of assemblages in neotropical cave dwelling bats based on their diet, wing morphology, and flight performance

Bats have a great variety of wing morphologies that determines the bat’s flight performance, and this in turn conditions the forage aerosphere and the food it can obtain. Several studies have shown differences in wing morphology, flight performance, and forage aerospheres among species from different trophic guilds. However, for species that share a guild this is not entirely clear. It is possible that these species have differences in their diet and show changes in wing morphology that modify their flight performance and forage areas. Determining this will allow a better understanding of spatial segregation among species that share a trophic guild. These studies allow the identification of species assemblages based on wing morphological differences and flight performance that would not be distinguished only by guild membership. Our goal was to define the species assemblages that make up a community of Neotropical cave dwelling bats based on their trophic guild, flight performance, and forage zone. A community of Neotropical cave dwelling bats from a cave in Veracruz, Mexico was analyzed. The diet of each species was determined by means of their stomach contents and bibliographic review. In addition, aspect ratio, wing loading and tip index were calculated. Based on the wing characteristics and diet, multivariate groupings and orders were performed, as well as to define the assemblages present. According to the wing characteristics and the dietary composition, four groups of species were found that represent four different flight characteristics in terms of agility and maneuverability. There was agreement between diet and wing characteristics, and the four trophic groups were identified through canonical correspondence analysis. Correlating wing morphology, diet and forage area allows us to adequately define the assemblages of a community of bats. Regarding the hypothesis, it was found that species that share a food guild show differences in the composition of their food and wing morphology, which generate differences in flight performance and forage areas. Four assemblages differing in forage aerospheres among three trophic guilds are described: understory and facultative artrhopodivorous, semi-clearing hematophages, and facultative nectarivores. Finally, spatial segregation between the species of the families Mormoopidae and Natalidae was recognized.

Predicting the population consequences of acoustic disturbance, with application to an endangered gray whale population.

Acoustic disturbance is a growing conservation concern for wildlife populations because it can elicit physiological and behavioral responses that can have cascading impacts on population dynamics. State-dependent behavioral and life history models implemented via Stochastic Dynamic Programming (SDP) provide a natural framework for quantifying biologically meaningful population changes resulting from disturbance by linking environment, physiology, and metrics of fitness. We developed an SDP model using the endangered western gray whale (Eschrichtius robustus) as a case study because they experience acoustic disturbance on their summer foraging grounds. We modeled the behavior and physiological dynamics of pregnant females as they arrived on the feeding grounds and predicted the probability of female and offspring survival, with and without acoustic disturbance and in the presence/absence of high prey availability. Upon arrival in mid-May, pregnant females initially exhibited relatively random behavior before they transitioned to intensive feeding that resulted in continual fat mass gain until departure. This shift in behavior co-occurred with a change in spatial distribution; early in the season, whales were more equally distributed among foraging areas with moderate to high energy availability, whereas by mid-July whales transitioned to predominate use of the location that had the highest energy availability. Exclusion from energy-rich offshore areas led to reproductive failure and in extreme cases, mortality of adult females that had lasting impacts on population dynamics. Simulated disturbances in nearshore foraging areas had little to no impact on female survival or reproductive success at the population level. At the individual level, the impact of disturbance was unequally distributed across females of different lengths, both with respect to the number of times an individual was disturbed and the impact of disturbance on vital rates. Our results highlight the susceptibility of large capital breeders to reductions in prey availability, and indicate that who, where, and when individuals are disturbed are likely to be important considerations when assessing the impacts of acoustic activities. This model provides a framework to inform planned acoustic disturbances and assess the effectiveness of mitigation strategies for large capital breeders.

Proportion of commodity crop pollens and pesticide contamination in honey bee diets in two different landscapes

Honey bees are the most important managed pollinators in commercial agriculture. Large irrigated mixed agricultural landscapes in the mid-south United States can be vital to maintaining commercial honey bee operations during times of prolonged nectar dearth, even if those crops are not dependent on bee pollinators. Severe declines in bee populations have generated concerns about the relationship of pesticide-treated seeds and crops and the health of honey bees. To investigate the role of pollen from seed-treated crops as a component of honey bee diet and pesticide contamination in pollen diet of honey bees from agricultural and urban landscapes, we monitored honey bee colonies in both agricultural and urban areas. Pollen collection began in mid-March, before seed-treated crops were planted, and continued through the end of August, after crops had ceased blooming. Pollen samples from returning bees were identified to determine the botanical origin of the bees’ pollen diet, and were also analyzed for pesticide contamination. Honey bees in the agricultural landscape visited crop sources only during the seasonal period of natural nectar dearth, when other wildflower sources were limited, and they encountered acutely toxic pesticide residues (above LD50) during this period. These bees also encountered toxic levels of herbicide on multiple occasions throughout the season, in pollen from non-crop plants. Bees in the urban area were also exposed to toxic levels of insecticides on several occasions. Urban bees were exposed to herbicides throughout the season, but not at concentrations approaching acute toxicity. Simultaneous exposure to multiple pesticides occurred at both sites on multiple occasions. The results underscore the need to conserve areas of habitat and forage for both wild and managed pollinators within both agricultural and urban landscapes.

Contrasting impacts of environmental variability on the breeding biology of two sympatric small procellariiform seabirds in south-eastern Australia.

Seabirds play a vital role in marine ecosystems and the long-term study of their responses to environmental variations can be used to monitor the effects of climate change on marine fauna. However, slight differences in similar seabird species result in a range of responses which complicates our understanding of the effects of environmental changes to marine ecosystems. The present study investigated inter-annual differences in the breeding biology (breeding phenology, chick growth rates and breeding success) and environmental conditions (seasonal sea surface temperatures) of important foraging areas in two sympatric small Procellariiform species, the fairy prion (Pachyptila turtur) and the common diving petrel (Pelecanoides urinatrix), over four reproductive seasons (2017–2020) in Bass Strait, south-eastern Australia. Marine heatwaves occurred during the years of 2018/19 and 2019/20 and coincided with years of delayed laying dates, slower chick growth and reduced breeding success, in both species. While fairy prions maintained a relatively high breeding success and broadly constant breeding phenology, common diving petrels delayed the start of the breeding season by up to 50 days and experienced dramatic collapses in breeding success in years of high marine heat wave occurrence. The difference in foraging ecology and physiological capacity (largely in the production of stomach oils and fasting abilities of adults and chicks) between both species are likely to influence the variability and phenology in the observed breeding seasons.

Untangling local and remote influences in two major petrel habitats in the oligotrophic Southern Ocean.

Ocean circulation connects geographically distinct ecosystems across a wide range of spatial and temporal scales via exchanges of physical and biogeochemical properties. Remote oceanographic processes can be especially important for ecosystems in the Southern Ocean, where the Antarctic Circumpolar Current transports properties across ocean basins through both advection and mixing. Recent tracking studies have indicated the existence of two large-scale, open ocean habitats in the Southern Ocean used by grey petrels (Procellaria cinerea) from two populations (i.e., Kerguelen and Antipodes islands) during their nonbreeding season for extended periods during austral summer (i.e., October to February). In this work, we use a novel combination of large-scale oceanographic observations, surface drifter data, satellite-derived primary productivity, numerical adjoint sensitivity experiments, and output from a biogeochemical state estimate to examine local and remote influences on these grey petrel habitats. Our aim is to understand the oceanographic features that control these isolated foraging areas and to evaluate their ecological value as oligotrophic open ocean habitats. We estimate the minimum local primary productivity required to support these populations to be much <1% of the estimated local primary productivity. The region in the southeast Indian Ocean used by the birds from Kerguelen is connected by circulation to the productive Kerguelen shelf. In contrast, the region in the south-central Pacific Ocean used by seabirds from the Antipodes is relatively isolated suggesting it is more influenced by local factors or the cumulative effects of many seasonal cycles. This work exemplifies the potential use of predator distributions and oceanographic data to highlight areas of the open ocean that may be more dynamic and productive than previously thought. Our results highlight the need to consider advective connections between ecosystems in the Southern Ocean and to re-evaluate the ecological relevance of oligotrophic Southern Ocean regions from a conservation perspective.

Genetic structure of olive ridley sea turtles (Lepidochelys olivacea) in Ghana, West Africa

Sea turtles migrate across ocean basins to reach foraging and breeding areas but still exhibit significant population structure across nesting beaches. Although five species of sea turtles nest in West Africa, the genetic structure of many species in this region has not been adequately explored. We investigated the diversity of mitochondrial and nuclear DNA for nesting olive ridley (Lepidochelys olivacea) turtles in two coastal communities (Mankoadze and Ada Foah) in Ghana that are approximately 160 km apart. Samples were collected during four nesting seasons: 2006, 2014, 2015 and 2016. Analysis of the control region of mtDNA (n = 45) revealed six variable positions defining five haplotypes, of which one was previously undescribed (Lo91). These findings are indicative of population expansion from a small ancestral population and support the scenario of colonization of the Atlantic via founder effect. Eleven microsatellite loci were used to analyze two years (2015 and 2016) from Mankoadze. We determined these nesting cohorts were not genetically distinct (FST = 0.025, P = 0.286) and can therefore be considered a single population. This population was compared to six females from Ada Foah across seven loci. Individuals from the two locations were less related than expected under a model of random chance, and showed signs of outbreeding, and reflected moderate variation between the two (FIS = -0.160, P = 1.00; FST = 0.104, P = 0.002). The structuring between locations indicate nesting individuals may utilize different migration routes, foraging grounds, or breeding grounds and that Ghana may serve as a transitional area between central and west African rookeries.

BIOTECHNOLOGIES FOR THE ORGANIZATION OF WINTER FOOD FOR THE WINTER POPULATION OF THE SIBERIAN ROE

To preserve the high number of roe deer in the territories of protected areas, it is not enough to apply disparate methods of winter feeding. It is necessary to develop a system for organizing winter meals. This requires the creation of large forage areas, the implementation of the principle of availability of forage crops in the period of high snow, mobile castling of forage resources in the protected area.

Novel pollen analogue technique shows bumblebees display low floral constancy and prefer sites with high floral diversity

ContextThere have been dramatic global declines in pollinating insects. A common land management intervention to support wild pollinators is to plant non-crop flowering plants (‘pollinator planting’). However, there are limited data on which species or spatial arrangement of planting provide maximum benefit to wild pollinators.ObjectivesHere we investigate which flowering species and locations are visited by free-foraging Bombus terrestris (buff-tailed bumblebees) in species-rich semi-natural grassland and woodland.MethodsTwo study nests of buff-tailed bumblebees were established in Wytham Woods, UK. Pollen analogue pigments were sprayed on open flowers in the study area over a period of two months, with unique colours used to identify separate sections of the study area. Pollen load analysis was used to identify forage species and foraging locations.ResultsBumblebees showed low flower constancy, visiting five flower species per trip on average, and as a group the sampled bumblebees visited 36 of the 49 plant species identified in study area surveys. Many individuals foraged in multiple, spatially-discrete locations during single trips.ConclusionsThe positive relationship between floral diversity and pollen load species diversity, and the positive relationship between site floral diversity and frequency of visitation, suggest behavioural strategies that maximize the diversity of flower species visited, in line with the energetic costs and benefits hypothesis. This supports recommendations for pollinator plantings with high species diversity, potentially spread across many small forage areas across the landscape.

Serendipitous observations from animal-borne video loggers reveal synchronous diving and equivalent simultaneous prey capture rates in chinstrap penguins

Seabirds often engage in coordinated, cooperative foraging to improve detection and capture of prey. An extreme example of such coordinated behavior is synchronicity, whereby the movements of individuals are aligned temporally and spatially. Synchronous diving among penguins has been reported, but simultaneous observations of predation by synchronously diving individuals have not. We instrumented chinstrap penguins (Pygoscelis antarcticus) during their incubation period in December 2019 from Cape Shirreff, Livingston Island, Antarctica (60.79°W, 62.46°S) with video and depth recorders to monitor predator foraging behavior and prey consumption rates. Serendipitously, two instrumented individuals, accompanied by a third, banded individual, engaged in synchronous foraging activities on Antarctic krill (Euphausia superba) for 9.25 h. This group formed ashore, transited together to their foraging area, remained in close visual contact after dives, synchronously timed diving behavior, and foraged at similar depths. Prey capture rates were positively correlated across dives and total consumption estimates were equivalent for the two instrumented birds during the video observation period. Video loggers confirmed that synchronous diving and foraging behavior are among the behavioral repertoire of chinstrap penguins and demonstrated equivalent prey capture rates by synchronously foraging predators. The results further suggest that group formation while ashore and group cohesion during a foraging trip may facilitate shared foraging success among group members.

Secondhand homes: The multilayered influence of woodpeckers as ecosystem engineers.

Ecosystem engineers alter, and can be influenced in turn by, the ecosystems they live in. Woodpeckers choose foraging and nesting sites based, in part, on food availability. Once abandoned, these cavities, particularly within areas of high forage, may be crucial to secondary cavity‐nesting birds otherwise limited by cavities formed through decay. Our study examined factors that influence the nesting success of primary cavity nesters and the subsequent impact on secondary cavity‐nesting birds. Using 5 years of point count data, we monitored the outcomes of cavity‐nesting birds in South Texas. We used logistic‐exposure models to predict daily survival rates based on cavity metrics and used woodpecker foraging trends and insect surveys to determine if nesting where woodpeckers actively forage benefits secondary cavity‐nesting birds. Both woodpeckers and secondary cavity nesters shared predictors of daily survival; nests were more successful in cavities with small openings in minimally decayed trees. All secondary cavity nesters had higher probabilities of success when nesting in an abandoned woodpecker cavity, opposed to ones formed by decay. Woodpeckers tended to forage in areas with higher‐than‐average levels of the insect orders Coleoptera, Hymenoptera, and Orthoptera, and secondary cavity nesters had higher rates of success when nesting in these areas. Our results suggest abandoned woodpecker cavities may be constructed in a way that directly benefit secondary cavity nesters. Additionally, we suggest an interplay between these ecosystem engineers, food availability, and secondary cavity nesters: Woodpeckers engineer superior nesting cavities in areas where food is more abundant, and the resultant cavities in areas of high forage may benefit local secondary cavity nesters. Our findings indicate that there is still much to be explored in the role of ecosystem engineers, and how they influence local communities on multiple trophic levels.