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Knowledge of seabird distributions plays a key role in seabird conservation and sustainable marine management, underpinning efforts to designate protected areas or assess the impact of human developments. Technological advances in animal tracking devices increasingly allow researchers to acquire information on the movement of birds from specific colonies. Nevertheless, most seabird colonies have not been subject to such tracking and another means must be found to assess their likely foraging distribution. Consequently, foraging range data collated and summarized across other tracking studies has often been used to estimate species‐level foraging distances for use within applied settings. However, generic species‐specific foraging ranges must be used with caution because of the amount of variation in seabird foraging behaviour at both the individual and colony levels. Specifically, although current reviews of seabird foraging ranges provide summary estimates of maximum foraging range, they typically do not assess the extent of among‐colony or among‐individual variation around such estimates. To address this, we conducted a variance component analysis of the maximum distance reached from the breeding colony per foraging trip (foraging range) using multi‐colony tracking datasets to estimate the degree of between‐individual, between‐year and between‐colony variation in foraging range in four UK breeding seabirds (Black‐legged Kittiwake Rissa tridactyla, Common Guillemot Uria aalge, Razorbill Alca torda and European Shag Gulosus aristotelis). We also provide updated estimates of typical foraging ranges for each species and quantify the influence of breeding stage and colony size. Overall, between‐colony variation was typically the largest variance component, explaining 20–30% of the observed variation in foraging range across the four species. Individual‐level variation was also relatively large among Shag. In Kittiwake, Guillemot and Shag, but not Razorbill, average foraging ranges were positively associated with colony size. In addition, Kittiwake and Razorbill travelled further during incubation than during chick‐rearing. More generally, our estimates of mean foraging ranges for each species were subject to a high degree of uncertainty, which should be incorporated into impact assessments carried out using such data. [ABSTRACT FROM AUTHOR]

How central-place foragers change search strategy in response to environmental conditions is poorly known. Foragers may vary the total distance traveled and how far they range from the central place in response to variation in the distribution of their prey. One potential reason as to why they would extend the length of their foraging trip and its distance from the colony would be to increase prey quality or quantity, despite incurring higher transit costs. To test this trade-off hypothesis in a species with high flight costs, we recorded the foraging behaviour of razorbills (Alca torca) using state-of-the-art techniques that log both individual horizontal (flight activity) and vertical (dive activity) movements. We show that the distance that razorbills traveled to foraging locations increased with sea-surface temperature, which may relate to higher prey quality or quantity. This relation is supported by an indirect index of patch quality, based on dive profiles, which also increased with travel distance from the colony. Furthermore, we show that this index was highest during the daily peak in diving activity, around midday. Taken together, these results suggest that razorbills are capable of adjusting their search strategies sensitively in response to proximate environmental cues., Introduction Foraging is a critical activity in an animal's life, and energy costs relative to energy intake determine many aspects of animal ecology. In particular, the ability to adjust foraging [...]

Large-scale interannual and decadal variation in ocean conditions, including sea-surface temperature (SST) has been shown to affect the breeding behaviour of marine birds in the North Pacific. However, as individual species respond differently to changing food supplies, our understanding of the role of climate variation in seabirds is limited. To examine the effect of ocean conditions on breeding behaviour, we measured incubation shift lengths of Ancient Murrelet (Synthliboramphus antiquus (Gmelin, 1789)), a small marine bird with exceptionally long incubation shift length, in seven, nonconsecutive years. We compared variation in shift length with interyear variation in regional SST. Incubation shifts were longer in years when March-May SST was higher. In years with longer shift length, birds have lower reproductive success. Our results suggested that Ancient Murrelets on Haida Gwaii can adjust their incubation patterns by extending their shift length in relation to SST fluctuations during breeding season. Key words: Ancient Murrelet, incubation shift length, Pacific, sea-surface temperature, Synthliboramphus antiquus. Il est connu que la variation a grande echelle entre les annees et les decennies des conditions oceaniques, en particulier de la temperature superficielle de la mer (SST), affecte le comportement reproducteur des oiseaux marins dans le Pacifique Nord. Cependant, puisque les especes individuelles reagissent differemment aux apports changeants de nourriture, notre comprehension du role de la variation climatique chez les oiseaux marins reste limitee. Afin d'examiner l'effet des conditions oceaniques sur le comportement reproducteur, nous avons mesure la duree des quarts d'incubation chez le guillemot a cou blanc (Synthliboramphus antiquus (Gmelin, 1789)), un petit oiseau marin dont les quarts d'incubation sont particulierement longs, durant sept annees non consecutives. Nous avons compare la variation des durees des quarts d'incubation avec la variation interannuelle de la SST regionale. Les quarts d'incubation durent plus longtemps pendant les annees durant lesquelles la SST en mars-mai est plus elevee. Les oiseaux ont un succes reproductif reduit les annees pendant lesquelles les quarts d' incubation durent plus longtemps. Nos resultats indiquent que les guillemots a cou blanc sur Haida Gwaii peuvent ajuster leurs modeles d'incubation en allongeant la duree des quarts en fonction des fluctuations de la SST durant la saison de reproduction. Mots-cles : guillemot a cou blanc, longueur des quarts d'incubation, Pacifique, temperature de surface de la mer, Synthliboramphus antiquus. [Traduit par la Redaction], Introduction Animals should adjust their behaviour to match prey phenology so that prey are most accessible when energy demands are highest (Lack 1950). For nidicolous birds, breeding is energetically demanding, [...]

Many species of Procellaridae are nocturnal on their breeding grounds, exhibiting reduced activity during fuller moonlight, perhaps to avoid predation by predators that use the full moon to hunt after sunset. Among these nocturnal species, Streaked Shearwaters Calonectris leucomelas have high wing loading and have difficulty taking off--especially with unfavorable wind conditions--thus potentially exacerbating moonlight avoidance. Effects of moonlight and wind conditions on the colony activity of this species, however, is poorly understood. We investigated the phenomenon by counting the departure and arrival of birds, and measuring ambient light intensity, local wind speed, and local wind direction at a breeding colony of Streaked Shearwaters on Awashima Island, Japan. Moon phase and ambient light had no significant effect on the frequency of arrivals or departures. Frequency of departures decreased significantly with increasing wind speed, but no effect was seen on arrivals, and wind direction had no effect on arrivals or departures. Our results indicate that: (1) wind speed may play an important role in Streaked Shearwater takeoff from the colony, and (2) moonlight avoidance is a plastic trait that may diminish in large-bodied shearwaters when few diurnal aerial predators are present. [ABSTRACT FROM AUTHOR]

Abstract: To prevent further global declines in biodiversity, identifying and understanding key habitats is crucial for successful conservation strategies. For example, globally, seabird populations are under threat and animal movement data can identify key at‐sea areas and provide valuable information on the state of marine ecosystems. To date, in order to locate these areas, studies have used global positioning system (GPS) to record position and are sometimes combined with time–depth recorder (TDR) devices to identify diving activity associated with foraging, a crucial aspect of at‐sea behaviour. However, the use of additional devices such as TDRs can be expensive, logistically difficult and may adversely affect the animal. Alternatively, behaviours may be resolved from measurements derived from the movement data alone. However, this behavioural analysis frequently lacks validation data for locations predicted as foraging (or other behaviours). Here, we address these issues using a combined GPS and TDR dataset from 108 individuals by training deep learning models to predict diving in European shags, common guillemots and razorbills. We validate our predictions using withheld data, producing quantitative assessment of predictive accuracy. The variables used to train these models are those recorded solely by the GPS device: variation in longitude and latitude, altitude and coverage ratio (proportion of possible fixes acquired within a set window of time). Different combinations of these variables were used to explore the qualities of different models, with the optimum models for all species predicting non‐diving and diving behaviour correctly over 94% and 80% of the time, respectively. We also demonstrate the superior predictive ability of these supervised deep learning models over other commonly used behavioural prediction methods such as hidden Markov models. Mapping these predictions provides useful insights into the foraging activity of a range of seabird species, highlighting important at sea locations. These models have the potential to be used to analyse historic GPS datasets and further our understanding of how environmental changes have affected these seabirds over time. [ABSTRACT FROM AUTHOR]

The diving capabilities of the Procellariformes remain the least understood component of avian diving physiology. Due to their relatively small size, shearwaters may have high oxygen consumption rates during diving relative to their available oxygen stores. Dive performance in this group should be strongly limited by the trade-off between oxygen consumption and oxygen stores, and shearwaters could be a good model group for testing predictions of dive theory. Many earlier measurements of shearwater dive behaviour relied on observations from the surface or potentially biased technology, and it is only recently that diving behaviour has been observed using electronic recorders for many of the clades within the family. The diving behaviour of Manx Shearwaters Puffinus puffinus breeding in Wales, UK, was studied on a large sample of birds using time-depth-temperature recorders deployed on chick-rearing shearwaters in July and August over 3 years (2009-2011). Light availability apparently limited diving as dives only occurred between 04:00 and 19:00 h GMT. All individuals routinely dived deeper than traditionally assumed, to a mean maximum depth of 31 m and occasionally down to nearly 55 m. We compiled all available data for a comparison of the dive depth across shearwater species. There was a positive allometric relationship between maximum dive depth and body mass across Puffinus and Ardenna shearwater species, as expected, but only if samples of fewer than two individuals were excluded. The large intra-specific range in maximum dive depth in our study illustrates that apparent diversity in diving performance across species must be interpreted cautiously. [ABSTRACT FROM AUTHOR]

The optimal allocation of time and energy between one's own survival and offspring survival is critical for iteroparous animals, but creates a conflict between what maximises the parent's fitness and what maximises fitness of the offspring. For central-place foragers, provisioning strategies may reflect this allocation, while the distance between central-places and foraging areas may influence the decision. Nevertheless, few studies have explored the link between life history and foraging in the context of resource allocation. Studying foraging behaviour alongside food load rates to chicks provides a useful system for understanding the foraging decisions made during parent-offspring conflict. Using simultaneously deployed GPS and time-depth recorders, we examined the provisioning strategies in free-living Manx shearwaters Puffinus puffinus, which were caring for young. Our results showed a bimodal pattern, where birds alternate short and long trips. Short trips were associated with higher feeding frequency and larger meals than long trips, suggesting that long trips were performed for self-feeding. Furthermore, most foraging was carried out within 100 km of sea fronts. A simple model based on patch quality and travel time shows that for Manx shearwaters combining chick feeding and self-maintenance, bimodal foraging trip durations optimise feeding rates. [ABSTRACT FROM AUTHOR]

CapsuleDive behaviour in Black GuillemotsCepphus gryllewas close to that predicted for a benthic forager by allometry based on body mass. AimsTo report the diving behaviour of Black Guillemots in Northern Ireland. MethodsA time-depth-recorders and GPS logger were deployed on four chick-rearing breeding Black Guillemots. ResultsDive shape implied most dives were benthic with a small number at the start of each bout associated with searching. Diving only occurred during daylight hours, but dive depth was unrelated to light availability outside of the twilight periods. Dive durations (max = 90 s; mean = 54 s) were shorter and dive depths (max = 15 m; mean = 9 m) were shallower than recorded for guillemots elsewhere. The birds dived a maximum of 1.8 km from the colony. ConclusionsBlack Guillemots' dive duration was similar to the value predicted from allometry, and is therefore likely representative of this species. Bathymetry likely influences the dive behaviour of this benthic-feeding species because most dives were U-shaped and dive depths were shallow, which is typical for the relatively shallow water where the birds were observed foraging. [ABSTRACT FROM AUTHOR]

Energy costs during breeding play an important role in the evolution of life history traits. Seabirds show substantial variation in both incubation shift length ( ISL) and metabolic rates. However, it is still unclear how variation in life history traits relates to incubation metabolic rates ( IMR). Here, we examine the relationship between IMR and life history traits, including ISL, fledging strategy (precocial to altricial), incubation period, nest location (surface vs. underground) and clutch mass relative to adult body mass for 30 species of seabirds collated from the literature. Using both conventional non-phylogenetic and phylogenetic generalized least-squares approaches, we show that IMR is negatively associated with ISL, relative clutch mass and with underground nesting, while fledging strategy and incubation period have no impact on IMR once phylogeny is accounted for. Maximum likelihood reconstructions further suggest than ancestral seabirds had average ISL and relative clutch mass, and were surface nesters. We conclude that lower metabolic rates during incubation are associated with both an increased incubation shift length that allows animals to travel farther, as well as the evolutionary emergence of underground nesting that requires less social interaction. [ABSTRACT FROM AUTHOR]

Theory and observations suggest that offspring abandonment in animals may occur when the costs to future reproductive output of current reproductive effort outweigh the fitness benefits of rearing the current brood. While hormonal cues (i.e. corticosterone) or energy reserves are believed to be involved, few studies have directly focused on the proximate cues influencing behaviours directly related to reproductive success. To address this information gap, we determined the incubation metabolic rates and corticosterone (CORT) levels of naturally fasting and freely incubating ancient murrelets (Synthliboramphus antiquus). Respiratory quotient (RQ) increased with date, suggesting that incubating ancient murrelets shifted from strictly lipid-based metabolism towards more protein-based metabolism as incubation progressed. Birds that hatched only one nestling had higher levels of circulating CORT than those which hatched two, suggesting that birds which laid only a single egg found incubation more stressful than those which laid two. However, CORT levels and incubation shift lengths were not correlated, suggesting that birds that undertook prolonged incubation shifts did so only when their energy stores were not jeopardized. [ABSTRACT FROM AUTHOR]

Background: Long-lived seabirds face a conflict between current and lifelong reproductive success. During incubation shifts, egg neglect is sometimes necessary to avoid starvation, but may compromise the current reproductive attempt. However, factors underlying this decision process are poorly understood. We focus on the ancient murrelet, Synthliboramphus antiquus, an alcid with exceptionally long incubation shift lengths, and test the impact of environmental factors on incubation shift length in relation to reproductive success. Methodology/Principal Findings: Using an information theoretic approach, we show that incubation shift length was a strong predictor of reproductive success for ancient murrelets at Reef Island, Haida Gwaii, British Columbia, Canada during the 2007 and 2008 breeding seasons. The most important factors explaining an individual's shift length were egg size, wind speed and the length of the mate's previous shift. Wind speed and tide height were the two most important factors for determining foraging behavior, as measured by dive frequency and depth. Conclusions/Significance: Our study demonstrates that (i) species-specific reproductive strategies interact with environmental conditions such as wind speed to form multiple incubation patterns and (ii) maintaining regular incubation shifts is an essential component of reproductive success. [ABSTRACT FROM AUTHOR]

Phenolic resin has the excellent properties of fire resistance, low smoke production during burning, and a good balance between its cost and mechanical properties compared with other types of resin used in fire-resistant polymers (FRPs). If phenolic resin can be employed as a matrix of FRP, such FRP can have a higher fire safety factor which will be a desirable property in the structures of vessels and railway carriages. However, for the case of the resole type of phenolic resin, water formed from the condensation reaction remains in the matrix, and this water evaporates resulting in the formation of voids during the curing process. In order to develop a new type of phenolic composite that can overcome this weakness, we used a foam type of phenolic resin and glass fibers as the matrix and the reinforcement, respectively. We, then, developed a new pultrusion technique for the new phenolic foam composite and examined its mechanical properties and thermal conductivity. In this paper, we report a new technique to mold not only a phenolic foam composite but also a sandwich beam in which the phenolic foam composite as a core and a thin phenolic FRP layer as a faceplate are used. We also investigated the compressive strength and elastic modulus under high temperatures and compared the result with that at room temperature. Finally, we show that the compressive properties of the phenolic foam composite and the sandwich beam are stable at higher temperatures. [ABSTRACT FROM AUTHOR]

Biologging has emerged as one of the most powerful and widely used technologies in ethology and ecology, providing unprecedented insight into animal behaviour. However, attaching loggers to animals may alter their behaviour, leading to the collection of data that fails to represent natural activity accurately. This is of particular concern in free-ranging animals, where tagged individuals can rarely be monitored directly. One of the most commonly reported measures of impact is breeding success, but this ignores potential short-term alterations to individual behaviour. When collecting ecological or behavioural data, such changes can have important consequences for the inference of results. Here, we take a multifaceted approach to investigate whether tagging leads to short-term behavioural changes, and whether these are later reflected in breeding performance, in a pelagic seabird. We analyse a long-term dataset of tracking data from Manx shearwaters (Puffinus puffinus), comparing the effects of carrying no device, small geolocator (GLS) devices (0.6% body mass), large Global Positioning System (GPS) devices (4.2% body mass) and a combination of the two (4.8% body mass). Despite exhibiting normal breeding success in both the year of tagging and the following year, incubating birds carrying GPS devices altered their foraging behaviour compared to untagged birds. During their foraging trips, GPS-tagged birds doubled their time away from the nest, experienced reduced foraging gains (64% reduction in mass gained per day) and reduced flight time by 14%. These findings demonstrate that the perceived impacts of device deployment depends on the scale over which they are sought: long-term measures, such as breeding success, can obscure finer-scale behavioural change, potentially limiting the validity of using GPS to infer at-sea behaviour when answering behavioural or ecological questions. [ABSTRACT FROM AUTHOR]

The article presents a study on optimization of dynamic soaring in a flap-gliding seabird affects its large-scale distribution at sea. It mentions that dynamic soaring harvests energy from a spatiotemporal wind gradient, allowing albatrosses to glide over vast distances. It reports how small-scale dynamic soaring affects large-scale Manx shearwater distribution at sea.

Large-scale climatic fluctuations, such as the El Niño-Southern Oscillation, can have dramatic effects on ocean ecosystem productivity. Many mobile species breeding in temperate or higher latitudes escape the extremes of seasonal climate variation through long-distance, even trans-global migration, but how they deal with, or are affected by, such longer phased climate fluctuations is less understood. To investigate how a long-lived migratory species might respond to such periodic environmental change we collected and analysed a 13 year biologging dataset for a trans-equatorial migrant, the Manx shearwater ( Puffinus puffinus ). Our primary finding was that in El Niño years, non-breeding birds were at more northerly (lower) latitudes than in La Niña years, a response attributable to individual flexibility in migratory destinations. Daily time spent foraging varied in concert with this latitudinal shift, with birds foraging less in El Niño years. Secondarily, we found that in subsequent breeding, a hemisphere away, El Niño years saw a reduction in foraging time and chick provisioning rates: effects that could not be attributed to conditions at their breeding grounds in the North Atlantic. Thus, in a highly migratory animal, individuals may adjust to fluctuating non-breeding conditions but still experience cascading carry over effects on subsequent behaviour.

Amidst the current biodiversity crisis, the availability of genomic resources for declining species can provide important insights into the factors driving population decline. In the early 1990s, the black-legged kittiwake (Rissa tridactyla), a pelagic gull widely distributed across the arctic, subarctic, and temperate zones, suffered a steep population decline following an abrupt warming of sea surface temperature across its distribution range and is currently listed as Vulnerable by the International Union for the Conservation of Nature. Kittiwakes have long been the focus for field studies of physiology, ecology, and ecotoxicology and are primary indicators of fluctuating ecological conditions in arctic and subarctic marine ecosystems. We present a high-quality chromosome-level reference genome and annotation for the black-legged kittiwake using a combination of Pacific Biosciences HiFi sequencing, Bionano optical maps, Hi-C reads, and RNA-Seq data. The final assembly spans 1.35 Gb across 32 chromosomes, with a scaffold N50 of 88.21 Mb and a BUSCO completeness of 97.4%. This genome assembly substantially improves the quality of a previous draft genome, showing an approximately 5× increase in contiguity and a more complete annotation. Using this new chromosome-level reference genome and three more chromosome-level assemblies of Charadriiformes, we uncover several lineage-specific chromosome fusions and fissions, but find no shared rearrangements, suggesting that interchromosomal rearrangements have been commonplace throughout the diversification of Charadriiformes. This new high-quality genome assembly will enable population genomic, transcriptomic, and phenotype-genotype association studies in a widely studied sentinel species, which may provide important insights into the impacts of global change on marine systems., (© The Author(s) 2023. Published by Oxford University Press on behalf of Society for Molecular Biology and Evolution.)

Plastic pollution is distributed patchily around the world's oceans. Likewise, marine organisms that are vulnerable to plastic ingestion or entanglement have uneven distributions. Understanding where wildlife encounters plastic is crucial for targeting research and mitigation. Oceanic seabirds, particularly petrels, frequently ingest plastic, are highly threatened, and cover vast distances during foraging and migration. However, the spatial overlap between petrels and plastics is poorly understood. Here we combine marine plastic density estimates with individual movement data for 7137 birds of 77 petrel species to estimate relative exposure risk. We identify high exposure risk areas in the Mediterranean and Black seas, and the northeast Pacific, northwest Pacific, South Atlantic and southwest Indian oceans. Plastic exposure risk varies greatly among species and populations, and between breeding and non-breeding seasons. Exposure risk is disproportionately high for Threatened species. Outside the Mediterranean and Black seas, exposure risk is highest in the high seas and Exclusive Economic Zones (EEZs) of the USA, Japan, and the UK. Birds generally had higher plastic exposure risk outside the EEZ of the country where they breed. We identify conservation and research priorities, and highlight that international collaboration is key to addressing the impacts of marine plastic on wide-ranging species., (© 2023. The Author(s).)

The hypersensitive response and pathogenicity (hrp) genes of Xanthomonas oryzae pv. oryzae, the causal agent of bacterial leaf blight of rice, encode components of the type III secretion system and are essential for virulence. Expression of hrp genes is regulated by two key hrp regulators, HrpG and HrpX; HrpG regulates hrpX and hrpA, and HrpX regulates the other hrp genes on hrpB-hrpF operons. We previously reported the sugar-dependent quantitative regulation of HrpX; the regulator highly accumulates in the presence of xylose, followed by high hrp gene expression. Here, we found that, in a mutant lacking the LacI-type transcriptional regulator XylR, HrpX accumulation and hrp gene expression were high even in the medium without xylose, reaching the similar levels present in the wild type incubated in the xylose-containing medium. XylR also negatively regulated one of two xylose isomerase genes (xylA2 but not xylA1) by binding to the motif sequence in the upstream region of the gene. Xylose isomerase is an essential enzyme in xylose metabolism and interconverts between xylose and xylulose. Our results suggest that, in the presence of xylose, inactivation of XylR leads to greater xylan and xylose utilization and, simultaneously, to higher accumulation of HrpX, followed by higher hrp gene expression in the bacterium.

Global wind patterns affect flight strategies in many birds, including pelagic seabirds, many of which use wind-powered soaring to reduce energy costs during at-sea foraging trips and migration. Such long-distance movement patterns are underpinned by local interactions between wind conditions and flight behaviour, but these fine-scale relationships are far less well understood. Here we show that remotely sensed ocean wind speed and direction are highly significant predictors of soaring behaviour in a migratory pelagic seabird, the Manx shearwater ( Puffinus puffinus ). We used high-frequency GPS tracking data (10 Hz) and statistical behaviour state classification to identify two energetic modes in at-sea flight, corresponding to flap-like and soar-like flight. We show that soaring is significantly more likely to occur in tailwinds and crosswinds above a wind speed threshold of around 8 m s -1 , suggesting that these conditions enable birds to reduce metabolic costs by preferentially soaring over flapping. Our results suggest a behavioural mechanism by which wind conditions may shape foraging and migration ecology in pelagic seabirds, and thus indicate that shifts in wind patterns driven by climate change could impact this and other species. They also emphasize the emerging potential of high-frequency GPS biologgers to provide detailed quantitative insights into fine-scale flight behaviour in free-living animals., (© 2017 The Author(s).)

Animals can be flexible in their migration strategies, using several wintering sites or a variety of routes. The mechanisms promoting the development of these migratory patterns and their potential fitness consequences are poorly understood. Here, we address these questions by tracking the dispersive migration of a pelagic seabird, the Atlantic puffin Fratercula arctica , using over 100 complete migration tracks collected over 7 years, including repeated tracks of individuals for up to 6 consecutive years. Because puffins have high flight costs, dispersion may generate important variation in costs of migration. We investigate differences in activity budgets and energy expenditure between different strategies. We find that puffins visit a range of overwintering destinations, resulting in a diversity of migratory routes differing in energy expenditures; however, they show interindividual similarity in the timings and location of major movements. We consider 3 hypothetical mechanisms that could generate this pattern: 1) random dispersion; 2) sex segregation; and 3) intraspecific competition or differences in individual quality. First, we dismiss random dispersion because individuals show strong route fidelity between years. Second, we find that sex differences contribute to, but do not account fully for, the migratory variation observed. Third, we find significant differences in breeding success between overwintering destinations, which, together with differences in foraging levels between routes, suggest that birds of different quality may visit different destinations. Taken together, our results show that dispersive migration is a complex phenomenon that can be driven by multiple factors simultaneously and can shape a population's fitness landscape.