Search

The distribution of seabirds at the macro scale (1000–3000 km) is influenced by physical and biological factors. Oceanic fronts represent important areas aggregating foraging seabirds, however, fronts can also act as barriers, possibly influencing their distribution patterns. Here, we investigated how fronts and environmental variables may drive the spatial distribution of seabird assemblages in the Southwestern Atlantic and Southern Oceans. Additionally, we tested if assemblages of seabirds fit into previously proposed biogeographical classifications, as these may work as surrogates to monitor assemblages. Seabird counts were carried out in November and March (2002, 2003, 2012). Sea surface temperature and salinity, bathymetry, chlorophyll-a, and the mean location of the Antarctic Circumpolar Current (ACC) fronts were used for the analysis of species composition. We used model-based multivariate methods to access differences in species composition across previously proposed biogeographic classifications. Model-based ordinations suggested no perfect fit of seabird species composition to these biogeographic classifications, with a high degree of overlap among their categories. However, multivariate generalised linear models indicated differences among them. Pairwise comparisons among biogeographic categories suggested differences in species composition resulted from categories to the north and to the south of the Antarctic Polar Front—Thalassarche melanophris, Procellaria aequinoctialis and Macronectes giganteus occurred in higher numbers to the north, whereas Pygocelis penguins and Thalassoica antarctica occurred only to the south. The results suggest that not all fronts in the ACC play a role in seabird distribution. Therefore, depending on the spatial scale of analysis, fronts do not necessarily dictate the biogeographical patterns of seabirds. [ABSTRACT FROM AUTHOR]

An invasive predator eradication campaign is planned for 2024 on Amsterdam Island, one of world's top priority island for seabird conservation. In order to monitor the effects on seabird colonies post-eradication, a survey of burrow-nesting species and population monitoring of albatrosses, penguins, skuas and terns was organised pre-eradication. Several counting techniques and acoustic methods were used to infer presence/absence of burrow-nesting species and to estimate abundance of other species, as well as genetic methods for species identification. In total 14 breeding (or probably breeding) seabird species were detected on Amsterdam Island, among which eight burrowing petrels including two species never described on the island: the Juan Fernandez petrel Pterodroma externa and the sooty sherwater Ardenna grisea. Based on these new data, the introduced mammal eradication campaign on Amsterdam, if successful, will likely be extremely beneficial for seabird conservation, and may also favor the colonization of Amsterdam by new seabird species. [ABSTRACT FROM AUTHOR]

The Late Quaternary fossil record indicates that formerly in the North Atlantic volcanic Macaronesian archipelagos (Azores, Madeira, Selvagens, Canary Islands, and Cape Verde) there was a higher avian diversity, including numerous now extinct species. Currently, only three gadfly petrels (genus Pterodroma) remain in two archipelagos: the Fea's petrel, Pt. feae , in Cape Verde (islands of Santiago, Fogo, Santo Antão, and São Nicolau); the Zino's petrel of Madeira, Pt. madeira , on the island of Madeira; and the Desertas petrel, Pt. deserta , on the islet of Bugio (Desertas Islands, Madeira Archipelago). Herein we describe the former distribution of the genus in Macaronesia based on the palaeontological record. However, the original specific diversity cannot be accurately established through the biometry of their fossil bones but the fossil record of Pterodroma in Macaronesia indicates: (i) its former presence in all Macaronesian archipelagos; (ii) the extinction of at least 16 island populations (73% of its original distribution on these islands); and (iii) the extinction of, at least, one species from Azores, here named Pterodroma zinorum sp. nov.. Radiocarbon dates indicate than this species was still alive at sometime among 1104 and 1672 CE, documenting its extinction in the last millennium. [ABSTRACT FROM AUTHOR]

Understanding the demography of wildlife populations is a key component for ecological research, and where necessary, supporting the conservation and management of long‐lived animals. However, many animals lack phenological changes with which to determine individual age; therefore, gathering this fundamental information presents difficulties. More so for species that are rare, highly mobile, migratory and those that reside in inaccessible habitats. Until recently, the primary method to measure demography is through labour intensive mark‐recapture approaches, necessitating decades of effort for long‐lived species. Gadfly petrels (genus: Pterodroma) are one such taxa that are overrepresented with threatened and declining species, and for which numerous aspects of their ecology present challenges for research, monitoring and recovery efforts. To overcome some of these challenges, we developed the first DNA methylation (DNAm) demography technique to estimate the age of petrels, using the epigenetic clock of Gould's petrels (Pterodroma leucoptera). We collected reference blood samples from known‐aged Gould's petrels at a long‐term monitored population on Cabbage Tree Island, Australia. Epigenetic ages were successfully estimated for 121 individuals ranging in age from zero (fledgling) to 30 years of age, showing a mean error of 2.24 ± 0.17 years between the estimated and real age across the population. This is the first development of an epigenetic clock using multiplex PCR sequencing in a bird. This method enables demography to be measured with relative accuracy in a single sampling trip. This technique can provide information for emerging demographic risks that can mask declines in long‐lived seabird populations and be applied to other Pterodroma populations. [ABSTRACT FROM AUTHOR]

While long-range transport is believed to be the primary source of mercury (Hg) in Antarctica, it is known that seabirds transport organic matter, nutrients, and contaminants from the sea to land. However, these biologically mediated inputs have not been widely evaluated. Anthropogenic contamination and natural occurrence have increased Hg in the environment. Antarctic seabirds, such as penguins and shags, form dense colonies and may provide an important local source of Hg input. This study determined the concentrations of total mercury (THg) in ornithogenic soils associated with eight species of seabirds on King George Island (Antarctica Peninsula) and evaluated species-specific differences. Soils from colonies of Southern Giant Petrel (Macronectes giganteus; mean ± SD, 213 ± 132 ng g−1) and Imperial Shag (Leucocarbo atriceps; 144 ± 54 ng g−1) had significantly higher THg concentrations than non-ornithogenically influenced (29 ± 35 ng g−1) soil samples. Soils associated with Southern Giant Petrels also had significantly higher THg than those of Kelp Gull (Larus dominicanus; mean 17 ± 15 ng g−1), which we speculate is a result of petrels occupying a higher trophic position in the marine food web, which leads to a greater accumulation of Hg in their organism, then being excreted through guano. Moreover, a moderate relationship observed between THg-Cd and THg-SOM suggests an influence of those species. Our data confirm that Antarctic seabird colonies are associated with higher soil THg concentrations and report the higher concentration for ornithogenically influenced soil (508 ng g−1) in a level similar to an anthropogenic site and highlight the need for a more thorough evaluation. [ABSTRACT FROM AUTHOR]

Background: Recent technological advances have resulted in low-cost GPS loggers that are small enough to be used on a range of seabirds, producing accurate location estimates (± 5 m) at sampling intervals as low as 1 s. However, tradeoffs between battery life and sampling frequency result in studies using GPS loggers on flying seabirds yielding locational data at a wide range of sampling intervals. Metrics derived from these data are known to be scale-sensitive, but quantification of these errors is rarely available. Very frequent sampling, coupled with limited movement, can result in measurement error, overestimating movement, but a much more pervasive problem results from sampling at long intervals, which grossly underestimates path lengths. Methods: We use fine-scale (1 Hz) GPS data from a range of albatrosses and petrels to study the effect of sampling interval on metrics derived from the data. The GPS paths were sub-sampled at increasing intervals to show the effect on path length (i.e. ground speed), turning angles, total distance travelled, as well as inferred behavioural states. Results: We show that distances (and per implication ground speeds) are overestimated (4% on average, but up to 20%) at the shortest sampling intervals (1–5 s) and underestimated at longer intervals. The latter bias is greater for more sinuous flights (underestimated by on average 40% when sampling > 1-min intervals) as opposed to straight flight (11%). Although sample sizes were modest, the effect of the bias seemingly varied with species, where species with more sinuous flight modes had larger bias. Sampling intervals also played a large role when inferring behavioural states from path length and turning angles. Conclusions: Location estimates from low-cost GPS loggers are appropriate to study the large-scale movements of seabirds when using coarse sampling intervals, but actual flight distances are underestimated. When inferring behavioural states from path lengths and turning angles, moderate sampling intervals (10–30 min) may provide more stable models, but the accuracy of the inferred behavioural states will depend on the time period associated with specific behaviours. Sampling rates have to be considered when comparing behaviours derived using varying sampling intervals and the use of bias-informed analyses are encouraged. [ABSTRACT FROM AUTHOR]

Unmanned sailboats can convert wind energy with sails to provide power for navigation, which can independently plan routes and collect data without human intervention. They have received increasing attention in recent years due to their low power consumption and strong self-sustainability. Due to the greater difficulty of manipulation, the unmanned sailboats have a weaker maneuverability than the propeller-driven vessels in the complex and variable marine environment. Typically, the turning motion is evaluated to characterize the maneuverability of a vessel, which has rarely been investigated in the existing research on unmanned sailboats. Therefore, this study builds a motion simulation platform for unmanned sailboats based on the 3 m class Petrel Sail to investigate the turning characteristics. The index of the approximate turning circle is introduced based on the turning motion trajectory, which is used to obtain the effect of rudder angle, wind angle, wind speed, and current speed on the turning performance of the sailboat in ideal hydrostatic conditions and under flow disturbance, respectively. Finally, a harbor pool test is conducted with an unmanned sailboat to verify the analysis results, and the errors in maximum transverse distance and maximum advance distance are in the reasonable range, proving the correctness of the theoretical results. The current study also provides theoretical guidance for subsequent research on sailboat manipulation and maneuverability. [ABSTRACT FROM AUTHOR]

Background: Seabirds like penguins and petrels, living in Antarctic and sub-Antarctic regions, often feed hundreds or even thousands of kilometers away from the islands where they breed. They therefore adapted to endure prolonged fasting during egg incubation, enabling their partner to undertake foraging trips that can last up to two weeks. Aside from accumulating and consuming fat reserves, it is unclear whether seabirds have developed further adaptations to extended fasting periods. This lack of knowledge is in part due to their remote nesting location and their extreme sensitivity to manipulation. To overcome this lack of knowledge, we developed a non-invasive device to record the heart rate (HR) of burrow-nesting blue petrels (Halobaena caerulea) during egg incubation. For that, we encapsulated a small-size logger in a dummy egg to record electrocardiograms (ECGs) through the featherless incubation patch of the birds. Results: The blue petrels' HR (208 ± 15 beats per min [bpm]; n = 6) that we recorded during egg incubation was slower than the HR predicted by two different allometric functions regressing HR against body mass (242 and 250 bpm). Blue petrels' HR also presented cyclical variation correlated to respiration, resembling the physiological Respiratory Sinus Arrhythmia (RSA) described in humans and other species, and that is mainly modulated by the vagal nerve. Moreover, the basal HR of incubating blue petrels increased about every minute during egg movements that presumably reflect egg turning, important for embryo survival and development. During these events, blue petrels' HR increased up to a maximum of 296 ± 27 bpm for 18 ± 2 s (n = 6). We estimated that those egg movements increased energy expenditure (EE) by 8.4 ± 1.3%, which is approximately 10 times less than the energy increase induced by the disturbance linked with the removal of the dummy egg at the end of the experiment. Interestingly, we noticed that the beginning of HR increase preceded egg movements by 4.3 ± 0.9 s (n = 6), as if birds needed to gradually increase their metabolism to achieve the following action. As well, blue petrels needed 9.1 ± 1.3 s (n = 6) to recover basal levels of HR after the end of egg movements. Conclusion: We recorded for the first time ECGs, HR and RSA in blue petrels in a completely non-invasive way. This allowed us to observe (1) slow basal HR during egg incubation, which could save energy for prolonged fasting and (2) temporal HR increase, possibly necessary to reposition the egg for proper embryonic development. [ABSTRACT FROM AUTHOR]

Artificial light at night (ALAN) is negatively impacting numerous species of nocturnally active birds. Nocturnal positive phototaxis, the movement towards ALAN, is exhibited by many marine birds and can result in stranding on land. Seabird species facing major population declines may be most at risk. Leach's Storm-Petrels (Hydrobates leucorhous) are small, threatened seabirds with an extensive breeding range in the North Atlantic and North Pacific Oceans. The Atlantic population, which represents approximately 40–48% of the global population, is declining sharply. Nocturnal positive phototaxis is considered to be a key contributing factor. The Leach's Storm-Petrel is the seabird species most often found stranded around ALAN in the North Atlantic, though there is little experimental evidence that reduction of ALAN decreases the occurrence of stranded storm-petrels. During a two-year study at a large, brightly illuminated seafood processing plant adjacent to the Leach's Storm-Petrel's largest colony, we compared the number of birds that stranded when the lights at the plant were on versus significantly reduced. We recorded survival, counted carcasses of adults and juveniles, and released any rescued individuals. Daily morning surveys revealed that reducing ALAN decreased strandings by 57.11% (95% CI: 39.29% - 83.01%) per night and night surveys revealed that reducing ALAN decreased stranding of adult birds by 11.94% (95% CI: 3.47% - 41.13%) per night. The peak stranding period occurred from 25 September to 28 October, and 94.9% of the birds found during this period were fledglings. These results provide evidence to support the implementation of widespread reduction and modification of coastal artificial light as a conservation strategy, especially during avian fledging and migration periods. [ABSTRACT FROM AUTHOR]

The New Zealand storm petrel (NZSP; Fregetta maoriana), thought to be extinct for over 150 years, was rediscovered in 2003. In 2013, a single NZSP breeding population was identified on Te Hauturu-o-Toi (Little Barrier Island) in the Hauraki Gulf off the east coast of Aotearoa New Zealand's North Island. Expeditions in 2021 to the Far North of New Zealand identified numerous NZSP at-sea over 300 km from Te Hauturu-o-Toi, suggesting that another breeding colony may exist. Blood samples collected from NZSP in the Hauraki Gulf and the Far North were used to generate genomic data. These data were analysed to investigate if individuals from the Far North are genetically differentiated from NZSP from the Hauraki Gulf, and if any individuals from the two locations are close relatives. Analyses revealed that NZSP from the Far North and Hauraki Gulf are not genetically distinct, and possible second-degree relatives were identified between the locations. Genetic diversity estimates indicated low population diversity levels and low effective population size estimates. These results suggest that Te Hauturu-o-Toi may be the only NZSP breeding colony, and the Far North represents a foraging location for NZSP. Sex bias fluctuates through the year but is similar in the two locations, also supporting a lack of population structure and indicating little foraging location bias between the sexes. Further research is needed to confirm whether highly connected or recently established colonies exist. These results highlight the extinction risk for NZSP and the importance of conservation efforts on Te Hauturu-o-Toi. [ABSTRACT FROM AUTHOR]

Human activities and climate change threaten seabirds globally, and many species are declining from already small breeding populations. Monitoring of breeding colonies can identify population trends and important conservation concerns, but it is a persistent challenge to achieve adequate coverage of remote and sensitive breeding sites. Southern giant petrels (Macronectes giganteus) exemplify this challenge: as polar, pelagic marine predators they are subject to a variety of anthropogenic threats, but they often breed in remote colonies that are highly sensitive to disturbance. Aerial remote sensing can overcome some of these difficulties to census breeding sites and explore how local environmental factors influence important characteristics such as nest-site selection and chick survival. To this end, we used drone photography to map giant petrel nests, repeatedly evaluate chick survival and quantify-associated physical and biological characteristics of the landscape at two neighboring breeding sites on Humble Island and Elephant Rocks, along the western Antarctic Peninsula in January–March 2020. Nest sites occurred in areas with relatively high elevations, gentle slopes, and high wind exposure, and statistical models predicted suitable nest-site locations based on local spatial characteristics, explaining 72.8% of deviance at these sites. These findings demonstrate the efficacy of drones as a tool to identify, map, and monitor seabird nests, and to quantify important habitat associations that may constitute species preferences or sensitivities. These may, in turn, contextualize some of the diverse population trajectories observed for this species throughout the changing Antarctic environment. [ABSTRACT FROM AUTHOR]

Mercury (Hg) is an environmental contaminant that can negatively impact the health of humans and wildlife. Albatrosses and large petrels show some of the highest levels of Hg contamination among birds, with potential repercussions for reproduction and survival. Here, body feather total Hg (THg) concentrations were determined in breeding adults of five species of albatrosses and large petrels in the foraging guild at South Georgia during the mid-2010s. We tested the effects of species, sex and trophic ecology (inferred from stable isotopes) on THg concentrations and compared our results with published values from past decades. Feather THg concentrations differed significantly among species (range: 1.9–49.6 µg g−1 dw), and were highest in wandering albatrosses Diomedea exulans, intermediate in black-browed albatrosses Thalassarche melanophris and northern giant petrels Macronectes halli, and lowest in southern giant petrels M. giganteus and white-chinned petrels Procellaria aequinoctialis. Females were more contaminated than males in all species, potentially due to differences in distributions and diet composition. Across species, THg concentrations were not correlated with feather δ13C or δ15N values, implying that species effects (e.g., breeding and moulting frequencies) may be more important than trophic effects in explaining feather THg concentrations in this foraging guild. Within species, the only significant correlation was between THg and δ13C in wandering albatrosses, which could reflect higher Hg exposure in subtropical waters. Comparisons with THg concentrations from past studies, which reflect contamination from 10 to > 60 years ago, revealed considerable annual variation and some evidence for increases over time for wandering and black-browed albatrosses since before 1950 and from the late 1980s, respectively. [ABSTRACT FROM AUTHOR]

Southern giant petrels (Macronectes giganteus) are important consumers that range across the oceans throughout the southern hemisphere. In Argentina, previous studies have shown they eat primarily pinnipeds and penguins, which they are assumed to scavenge, although there are occasional anecdotes of them attacking living penguins. Here we describe a predation attempt by a trio of southern giant petrels on a molting adult Magellanic penguin (Spheniscus magellanicus) at the large colony at Punta Tombo, Argentina. We relate giant petrel attendance patterns at the colony to the penguins' phenology, showing how giant petrel numbers rise with the increasing prevalence of vulnerable penguins. We suggest that living penguins—both fledglings and adults—may constitute a more seasonally significant proportion of the giant petrel diet than previously assumed, and their capture may represent a specialized predation technique. [ABSTRACT FROM AUTHOR]

Despite the sensitivity of ecosystems in extreme conditions, only 0.029% of the Antarctic continent is currently granted special protection as Antarctic Specially Protected Area (ASPA). Additionally, protected areas are unevenly distributed and unrepresentative of the biodiversity of Antarctica. The Antarctic Treaty Consultative Parties are thus striving to establish a more coherent network of protected areas. In this context, the Otto-von-Gruber-Gebirge was identified as an area highly worthy of protection due to its unique ecosystem including one of the largest snow petrel breeding sites, and relative pristine nature. However, in the process of designation, an update of knowledge, particularly of the population status of snow petrel in the area, was recognized to be needed. This study was aimed at estimating a population census of snow petrel breeding pairs in the Lake Untersee catchment, an important subarea of the potentially protected area. Investigations were severely limited by the remoteness and harsh conditions of the area, enabling only a short fieldwork period with limited resources. Thus, a combination of remote sensing and traditional methods was applied. We conducted a ground survey of a smaller reference area, including locating nest sites and assessing nest site characteristics. Snow petrels usually nest in the cavities of large boulders and we thus classified habitat suitability based on boulder presence. To do so, the study area was remotely surveyed by unpiloted aerial vehicles to gain orthophotomosaics in sufficient resolution to distinguish on-ground conditions for breeding. We then calculated nest site densities for the reference area. We also studied nest site data such as nest cavity depth, orientation, and attendance to gain basic knowledge of the characteristics of the breeding site. Finally, we measured a sample of four live snow petrels to determine which morph was present at the site. We were able to obtain nest site data and to extrapolate it, which produced population numbers of 11,765 breeding pairs for the whole study area. This underpins the size of the breeding site and thereby its importance for the species. [ABSTRACT FROM AUTHOR]

This note summarises key identification criteria for Fuegian Storm Petrel Oceanites oceanicus chilensis that permit field separation from Wilson's Storm Petrel O. o. oceanicus/exasperatus. Multiple sightings of presumed Fuegian Storm Petrel off São Tomé are considered in the light of these identification criteria. Here, we establish a provisional range for presumed Fuegian Storm Petrels in the Atlantic based on relevant literature, photographs in the Macaulay Library, and responses to social media requests. [ABSTRACT FROM AUTHOR]

We report the development of a colony of threatened Newell's Shearwater Puffinus newelli (NESH) at Makamaka'ole, West Maui, USA, a successful first undertaking in the Hawaiian Islands. Efforts involved the construction of two predator-proof fenced areas, removal/control of predators, placement of nest boxes, and social attraction using recorded calls and decoys. Initially, one of the management areas was intended for Hawaiian Petrel Pterodroma sandwichensis (HAPE) and the other for NESH. Exclosures were completed and mammalian predators were removed in 2013, and social attraction began in 2014. Both species almost immediately began flyovers to inspect speakers and by 2015, they had landed to inspect nest sites. Cameras recorded activity at nests during which individuals showed interest and, in at least one case, competed for the same nest. The first NESH eggs were laid in 2017, by which time HAPE had lost interest. NESH numbers continued to grow, especially after more speakers were added in 2019, when at least one but as many as five NESH chicks fledged. Two main questions arose: 1) What was the source population from which NESH had come, given their near extirpation on Maui? and 2) Why did HAPE, which are abundant in East Maui and on the nearby island of Lāna'i, eventually lose interest? Better understanding the population and behavioral ecology of these species might well inform planning for similar projects elsewhere in Hawai'i. [ABSTRACT FROM AUTHOR]

We report predation by an Arctic Fox Alopex lagopus on two seabird species, Atlantic Puffins Fratercula arctica and Leach's Storm Petrels Hydrobates leucorhous, nesting on Bakeapple Island, Little Fogo Islands, Newfoundland, Canada. This event took place in 2022, when a whole-island inspection revealed that fox, facilitated by over-ice invasion, killed at least 139 adult storm petrels and 8 puffin chicks. The fox also dug out 83 storm petrel and 4 puffin burrows. Breeding by seabirds on the island, which harbours some of the northernmost colonies in Newfoundland, was also largely disrupted; we documented extremely low egg and chick production values associated with the fox's presence and activity. We discuss the implications of such events for local seabird populations and the need for long-term monitoring to fully understand the impact of these predation events. [ABSTRACT FROM AUTHOR]

On 16 May 2021, a storm petrel was photographed on a pelagic trip in the Benguela Current off Cape Town, South Africa, exhibiting the diagnostic features of Pincoya Storm Petrel Oceanites pincoyae. This sighting occurred far from other records, the closest being approximately 7500 km away. The record, therefore, requires us to reassess our understanding of the movements and ecology of Pincoya Storm Petrel, which was previously known only from shallow waters in fjords and adjacent seas in south-central Chile. Pincoya Storm Petrel is considered Data Deficient by the International Union for Conservation of Nature (IUCN), the breeding range remains unknown, and the population was estimated to number only around 3000 individuals. While Pincoya Storm Petrel is recognised as a valid species by the International Ornithological Congress (IOC), eBird/Clements checklists, and the South American Classification Committee, its taxonomic status has been questioned. This sighting of a bird with all the features of Pincoya Storm Petrel distant from previous sightings, and in a markedly different ecological setting, may lead us to re-evaluate our understanding of species limits and phenotypic variation in Oceanites storm petrels. Further research to collect phenotypic, phylogenetic, and phenological data will allow us to re-examine species boundaries in Oceanites and enhance our understanding of this fascinating genus. [ABSTRACT FROM AUTHOR]

Little is known on seabirds of the order Procellariiformes which visit the Brazilian oceanic islands. Herein, we present new records of five birds found stranded in the Fernando de Noronha archipelago: Fregetta tropica melanoleuca Salvadori, 1908, Ardenna grisea (Gmelin, 1789), Puffinus lherminieri Lesson, 1839, and Hydrobates leucorhous (Vieillot, 1818). Citizen‑science platforms include only one documentation for each of these species, but there is potential for greater detection. Pelagic birds have rarely been reported in recent decades, and continued monitoring is needed for better understanding of their distribution patterns.

Intraspecific phenotypic variability is key to respond to environmental changes and anomalies. However, documenting the emergence of behavioral diversification in natural populations has remained elusive due to the difficulty of observing such a phenomenon at the right time and place. Here, we investigated how the emergence of a new trophic strategy in a population subjected to high fluctuations in the availability of its main trophic resource (migrating songbirds) affected the breeding performance, population structure, and population fitness of a specialized color polymorphic predator, the Eleonora's falcon from the Canary Islands. Using long-term data (2007–2022), we found that the exploitation of an alternative prey (a local petrel species) was associated with the growth of a previously residual falcon colony. Pairs in this colony laid earlier and raised more fledglings than in the other established colonies. The specialization on petrels increased over time, independently of annual fluctuations in prey availability. Importantly, however, the positive effect of petrel consumption on productivity was stronger in years with lower food availability. This trophic diversification was further associated with the genetically determined color morph, with dark individuals preying more frequently on petrels than pale ones, which might promote the long-term maintenance of genotypic and phenotypic diversity. We empirically demonstrate how the emergence of an alternative trophic strategy can buffer populations against harsh environmental fluctuations by stabilizing their productivity. [ABSTRACT FROM AUTHOR]

Gadfly petrels are among the widest-ranging birds and inhabit oceanic regions beyond the legislative protection of national jurisdictions (the High Seas). Detailed information on breeding phenology, at-sea distributions, and habitat requirements is crucial for understanding threats and designing conservation measures for this highly threatened group. We tracked 10 Stejneger's petrels Pterodroma longirostris, endemic to Isla Alejandro Selkirk, Juan Fernández Islands in the southeast Pacific Ocean, with geolocator-immersion loggers over two years to examine year-round movements, phenology, habitat use, and activity patterns. Birds conducted round-trip trans-equatorial migrations of 54,725 km to the northwest Pacific Ocean between Hawaii and Japan. Across the boreal summer, birds followed the c. 1000 km northward movement of the North Pacific Transition Zone Chlorophyll Front, before their return migration which took a long detour south toward New Zealand before heading east at 40–50°S, presumably benefitting from Antarctic circumpolar winds. To our knowledge, a comparable triangular migration is unique among seabirds. During the pre-laying exodus, birds traveled southwest to the Sub-Antarctic Front, and unlike congeners, there was no evidence of sexual segregation. Foraging areas during incubation were similar to pre-laying, with trips lasting 13 d and taking birds up to 4810 km southwest of the colony. Petrels spent > 75% of their time flying during breeding and migration, yet flight activity was substantially lower during non-breeding, presumably due to flight feather molt. Birds spent 87% of their time at sea within the High Seas and their apparent preference for oceanic frontal regions demonstrates the importance of protecting these remote habitats. [ABSTRACT FROM AUTHOR]

Bycatch risk assessments typically rely on spatial overlaps between seabirds and fishing vessels but should also consider seabirds' position in the attraction spectrum. Investigating seabird-fishery interactions in relation to habitat use is vital for species-specific risk assessments. To address this, we studied interactions between sooty albatrosses (SA) and white-chinned petrels (WCP) with fisheries. GPS data from 20 SA and 18 WCP individuals from Marion Island were analysed alongside Automatic Identification System-derived boat locations over two breeding seasons. We calculated encounter and attraction rates and correlated them with marine habitat characteristics. SA interactions occurred in deeper, warmer waters compared to their foraging habitat when vessels were absent, with 20% of individuals encountering and only 5% being attracted to boats. In contrast, WCP interactions occurred in shallow, warm South African shelf waters, consistent with their typical foraging habitats, with 72% encountering and 56% attracted to boats. These results highlight the need for continued reinforcement of mitigation measures for WCP. Despite the low attraction rates for SA, ongoing vigilance is required due to their smaller population size, which heightens the potential impact of illegal fisheries. The comparison of species along an attraction spectrum contributes to refining risk assessments and informs species-specific conservation strategies. [ABSTRACT FROM AUTHOR]

Little is known on seabirds of the order Procellariiformes which visit the Brazilian oceanic islands. Herein, we present new records of five birds found stranded in the Fernando de Noronha archipelago: Fregetta tropica melanoleuca Salvadori, 1908, Ardenna grisea (Gmelin, 1789), Puffinus lherminieri Lesson, 1839, and Hydrobates leucorhous (Vieillot, 1818). Citizen-science platforms include only one documentation for each of these species, but there is potential for greater detection. Pelagic birds have rarely been reported in recent decades, and continued monitoring is needed for better understanding of their distribution patterns. [ABSTRACT FROM AUTHOR]

Marine protected areas (MPAs) are widely used tools for conservation and management. Their correct delimitation is challenging, especially when the target species are small, elusive and inconspicuous, as little data are generally available to adequately assess their distribution at sea. Therefore, currently designated MPAs may not effectively cover key areas for small seabirds, particularly during migration and wintering seasons.We used ensemble species distribution models (ESDMs) on a 15‐year time‐series data set of at‐sea census along the Atlantic Iberian arc to predict the potential distribution of the smallest European seabird, the European storm‐petrel (Hydrobates pelagicus), and compare it with official marine special protection areas (SPAs).Occurrence of European storm‐petrel was related to shifts in sea surface temperature, and to small distances from the coast over the continental shelf.Most relevant area for the species in the Atlantic Iberian arc was west‐central Portugal to north‐western coast of the Iberian Peninsula, with an additional key area in the Gulf of Cádiz. Both zones host significant SPAs, but they inadequately cover key areas for European storm‐petrels. Our findings support extending marine SPAs in the Atlantic Iberian arc to ensure their effective protection.The distribution of the species expands over the years, varying in both size and location. These changes might be attributed to dynamic oceanographic variables, such as sea surface temperature and biomass of micronekton, which seem to play a significant role in their foraging behaviour.Synthesis and applications. Our study highlights the importance of analysing long time series and ESDMs to design adequate protected areas, which ensure the conservation of small and highly mobile species such as storm petrels. Our results should be considered by decision‐makers to prioritise and update marine protected areas, while incorporating the dynamic nature of the ocean within an ecosystem‐based approach. [ABSTRACT FROM AUTHOR]

Seabird bycatch in fisheries, and the development of effective mitigation to minimize this, have been subject to increasing research attention over the past three to four decades. Trawl fisheries represent a particular challenge, as bird mortalities (especially highly threatened albatrosses and large petrels, Procellariforms) occur primarily through difficult-to-detect collisions with warp and net monitoring cables. Effectiveness of bird-scaring lines (BSLs) as a mitigation measure can be fleet-specific, and studies relating specifically to reducing collisions with the net monitoring cable are rare. To support improved assessment and mitigation of seabird bycatch in trawl fisheries, we studied the mortality associated with mid-water and bottom factory trawl vessels along the southern tip of the Argentine Patagonian shelf, across 2144 trawls from 2012 to 2019, with three specific objectives: (i) inform improved bycatch management in this (and other) trawl fisheries by analysing differences in seabird collision rates and outcomes between net monitoring and warp cables, as well as the effect of mitigation measures in reducing collisions; (ii) explore the effects of key fishing operation variables on seabird impact outcomes; and (iii) estimate the annual seabird mortality in the study fleet. We tested the efficacy of BSLs as a mitigation measure to reduce seabird mortality, on warps and net monitoring cables. Our results show that seabird mortality increases in the presence of a net monitoring cable. Our estimation of fishery-wide mortality without the use of BSLs includes 108 [31–186] Southern royal albatross (Diomedea epomophora) and 279 [108–465] Black-browed albatross (Thalassarche melanophris) killed annually by the collisions with the net monitoring cable. We demonstrate the efficacy of BSLs in reducing the number of collisions and in combination with no discarding of fishes, seabird interactions fell to c. zero. Our study builds the case for better bycatch data collection in trawl fisheries, the strong influence of discarding, and the feasibility of simple mitigation measures to reduce seabird bycatch, including on the net monitoring cable. [ABSTRACT FROM AUTHOR]

In wild vertebrates, the increase of breeding success with advancing age has been extensively studied through laying date, clutch size, hatching success, and fledging success. However, to better evaluate the influence of age on reproductive performance in species with high reproductive success, assessing not only reproductive success but also other proxies of reproductive performance appear crucial. For example, the quality of developmental conditions and offspring phenotype can provide robust and complementary information on reproductive performance. In long-lived vertebrate species, several proxies of developmental conditions can be used to estimate the quality of the produced offspring (i.e., body size, body condition, corticosterone levels, and telomere length), and therefore, their probability to survive. By sampling chicks reared by known-aged mothers, we investigated the influence of maternal age on reproductive performance and offspring quality in a long-lived bird species, the snow petrel (Pagodroma nivea). Older females bred and left their chick alone earlier. Moreover, older females had larger chicks that grew faster, and ultimately, those chicks had a higher survival probability at the nest. In addition, older mothers produced chicks with a higher sensitivity to stress, as shown by moderately higher stress-induced corticosterone levels. Overall, our study demonstrated that maternal age is correlated to reproductive performance (hatching date, duration of the guarding period and survival) and offspring quality (body size, growth rate and sensitivity to stress), suggesting that older individuals provide better parental cares to their offspring. These results also demonstrate that maternal age can affect the offspring phenotype with potential long-term consequences. [ABSTRACT FROM AUTHOR]

The demography and factors affecting the population dynamics of gadfly petrels (Pterodroma spp.) remain poorly known, although they constitute the most diverse genus of Procellariiformes and many species are threaten. Using a long-term individual monitoring dataset over 35 years, this study provides estimates of state-specific demographic parameters of the White-headed Petrel (Pterodroma lessonii) from Mayes Island, Kerguelen archipelago, and tests for the effects of environmental factors. Age at first breeding was 8.7 ± 2.6 years and apparent adult annual survival was 0.941 ± 0.058. Annual breeding probability was 0.356 ± 0.036 for successful breeders and 0.988 ± 0.054 for individuals that took a sabbatical year after a successful breeding event. Successful breeders that bred during two consecutive years had a lower breeding success (0.574 ± 0.048) that individuals that bred after a sabbatical year (0.655 ± 0.036). The realized population growth rate (1.073 ± 0.011) suggested that the population is increasing. There was a slight evidence for a positive effect of the Southern Annular Mode on the breeding probability of successful breeders, but no effect of sea surface temperature, chlorophyll a or wind was detected on demographic parameters. This study revealed that White-headed Petrels had a particularly high adult survival coherent with a quasi-biennial strategy and late age at first breeding. According to life history theory, populations of White-headed Petrel are thus likely to be very sensitive to small variations in adult survival, and anthropogenic factors causing additive mortality such as introduced predators will constitute serious threats for this species. [ABSTRACT FROM AUTHOR]

This study deals with the interpretation of structural 3D seismic reflection of the Kumait oil field in southern Iraq within the administrative boundaries of the Maysan Governorate. Synthetic seismograms are prepared by using available data of the Kt-1 oil field by using Petrel software to define and pick the reflector on the seismic section of the Zubair Formation, Which represents the Cretaceous Age. The study shows that the Kumait structure is an anticline fold. It is thought to be a structure trap caused by the collision of the Arabian and Iranian plates and trending in the same direction as driving factors in the area, which are from the northwest to the southeast, and the overall trend of strata is north and northeast. Seismic structure interpretation results show the top of the Zubair Formation and several structure closures. The stratification Phenomenon of the study area was clear evidence of the existence of closures which are probable to be hydrocarbon traps. [ABSTRACT FROM AUTHOR]

Shifts in zooplankton communities due to changing ocean climate can affect foraging patterns among planktivorous seabirds. To better understand seabird response to environmental change in Bass Strait, southeast Australia, we investigated the prey species and 16 elements in prey and feathers of the planktivorous White-faced Storm Petrel Pelagodroma marina. The krill Nyctiphanes australis was the most abundant prey species, followed by several species of post-larval fish; otherwise, the species appeared to be a generalist feeder. Element concentrations of feathers were not significantly influenced by dietary composition. Likewise, element concentrations did not significantly differ between major prey species, confirming that the nutritional profile of these species is likely linked to their seawater environment. Given that Whitefaced Storm Petrels in Bass Strait substantially rely on a narrow range of prey species, this may increase their vulnerability to events that change their availability. As coastal krill is highly sensitive to sea surface temperatures (SST), the increases in SST predicted under climate change scenarios may alter the timing and abundance of krill swarms, which in turn may affect planktivores, including White-faced Storm Petrels. [ABSTRACT FROM AUTHOR]

Man-made debris is a global problem for seabirds because it is ingested by many species. Markham's Storm Petrel Hydrobates markhami, which breeds in the Atacama Desert and is endemic to the Humboldt Current in the eastern South Pacific, has been poorly studied in this regard. Earlier studies found low levels of man-made debris in the species' diet. We quantified the present-day frequency-occurrence of man-made debris in fledglings and adults of Markham's Storm Petrel in Chile. We found that 16 of 25 fledglings and all adults contained man-made debris in their digestive tract, indicating the prevalence of man-made debris in this species' diet is higher than previously reported. Additional work is needed to assess the importance of this finding to conservation efforts. [ABSTRACT FROM AUTHOR]

At-sea distributions of seabird species are strongly associated with the distribution patterns of their prey, which are influenced by physical oceanic features. During breeding and non-breeding seasons, seabirds move extraordinary distances among different environments. However, foraging site fidelity by seabirds appears to be high in areas of known high productivity, such as frontal zones and upwellings. Here, we present a tracking study for the Peruvian diving-petrel Pelecanoides garnotii, an endemic seabird of the highly productive Humboldt Current System, to assess whether adults use the same foraging areas throughout the year, combining data from nest monitoring and global location sensors (GLS) deployed on 12 individuals between two breeding seasons (2013–2014 and 2014–2015), in Choros Island (29°15′S; 71°32′W), Chile. Two main foraging areas were registered. During the breeding season, adults moved in the northern direction, between 60 to 144 km away from their colony, foraging in areas with high primary productivity. During the non-breeding period, they moved to southern latitudes (~ 1200 km). Adults spent 37% and 63% of their time in flight/land and on/underwater activities, respectively. We determined that birds move northward from their colony during breeding, where prey availability seems more predictable throughout the year. However, during the non-breeding period, it is likely that other environmental factors influence the distribution pattern of the Peruvian diving-petrel. [ABSTRACT FROM AUTHOR]

The Bermuda petrel Pterodroma cahow is an island endemic seabird that belongs to the Procellariiformes, one of the most endangered orders of birds. Historical records suggest a significant population size decline following human settlement in Bermuda, bringing the species to near extinction. Since the 1950s, the population has been recovering aided by the implementation of an ongoing conservation plan. However, it still faces several threats, and negative genetic effects resulting from that drastic decline are to be expected, including inbreeding and genetic drift. We studied genetic diversity and levels of inbreeding, and their effects on individual fitness and mating choice. We also tested for a genetic signature of the recent demographic bottleneck. For this, we analyzed variation in thousands of nuclear single-nucleotide polymorphisms derived from double digest restriction site-associated DNA sequencing and 1 mitochondrial gene (cytochrome oxidase I). The results revealed that the Bermuda petrel suffered a recent genetic bottleneck and shows low mitochondrial diversity compared with other petrel species. Conversely, nuclear diversity was similar to that of other endangered petrels. Inbreeding levels were not high overall, although some individuals were highly inbred. However, we found no evidence that individual inbreeding or relatedness between mates affected hatching success, or that mate choice is influenced by kinship in this very small population. [ABSTRACT FROM AUTHOR]

Copyright of Iraqi Journal of Chemical & Petroleum Engineering is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hypogean petrels return to the same nest burrow to breed on remote islands during the summer months. Their nocturnal behavior at the colony, strong musky odor and olfactory anatomy suggest an important role of olfaction in homing behavior and nest recognition. Behavioral experiments showed that olfactory cues are sufficient to allow nest identification, suggesting a stabile chemical signature emanating from burrows and facilitating nest recognition. However, the chemical nature and sources of this odor remain unknown. To better understand the nest odor composition, we analyzed volatile organic compounds (VOCs) of nests of blue petrels (Halobaena caerulea) derived from three different odor sources: nest air, nest material and feather samples. We also compared, during two successive years, VOCs from burrows with an incubating breeder on the nest, and burrows used during the breeding season by blue petrels but shortly temporally unoccupied by breeders. We found that the nest air odor was mainly formed by the owners' odor, which provided an individual chemical label for nests that appeared stabile over the breeding season. These findings, together with the previous homing behavioral studies showing an essential role of the sense of smell in blue petrels, strongly suggest that the scent emanating from burrows of blue petrels provides the information that facilitates nest recognition and homing. [ABSTRACT FROM AUTHOR]

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. Petrels are wide-ranging, highly threatened seabirds that often ingest plastic. This study used tracking data for 7,137 petrels of 77 species to map global exposure risk and compare regions, species, and populations. The results show higher exposure risk for threatened species and stress the need for international cooperation to tackle marine litter. [ABSTRACT FROM AUTHOR]

Seabirds often spend time on the water in the vicinity of their breeding colonies at the start or end of foraging trips, which may be for bathing, social interaction, information transfer, or to reduce predation risk for small petrels that prefer to return to land in darkness. Although such behaviour (hereafter rafting) is common, there are few data on variation in its incidence or timing across species, or analyses of relationships with intrinsic or extrinsic factors such as breeding stage (reflecting central-place foraging constraints) or weather. Here, we use GPS and immersion data collected over multiple years at Bird Island, South Georgia, to investigate rafting behaviour of four albatross and one burrow-nesting petrel species. Nearly all tracked birds (89%) landed within 10 km of the colony at the start of foraging trips for ~ 30 min, whereas only 17% did so at the end, suggesting they likely use rafting mainly for plumage maintenance after extended breeding shifts on land. Rafting duration, distance and bearing from the colony varied markedly according to species, wind speeds and period of the day (daylight vs. darkness), which may reflect differences in foraging direction, time constraints, degree of plumage soiling, diel activity patterns, or the requirement for high wind speeds for efficient flight. Given that all the study populations are decreasing, and most individuals make extensive use of nearshore waters during the breeding season, effective marine spatial planning is required that eliminates or mitigates human risks around their colonies. [ABSTRACT FROM AUTHOR]

Numerous seabird species are experiencing population declines, and this trend is expected to continue or even accelerate in the future. To understand the effects of environmental change on seabird populations, long-term studies are vital, but rare. Here, we present over four decades (1978–2020) of population dynamic and reproductive performance data of Wilson's Storm Petrels (Oceanites oceanicus) from King George Island (Isla 25 de Mayo), Antarctica. We determined temporal trends in population size, breeding output, and chick growth rates, and related interannual variation in these variables to various environmental variables. Our study revealed a decline of 90% in population size of Wilson's Storm Petrels in two colonies, and considerable changes in breeding output and chick growth rates. Temporal changes in breeding demographics were linked to interannual environmental variation, either causing changes in food availability (particularly Antarctic krill, Euphausia superba) or in nest burrow accessibility due to snow blocking the entrance. With the expected rise in air and sea surface temperatures, the predicted increases in precipitation over the Antarctic Peninsula will likely lead to increased snowstorm prevalence. Additionally, the rising temperatures will likely reduce food availability due to reduced sea ice cover in the wintering grounds of Antarctic krill, or by changing phyto- and zooplankton community compositions. The ongoing environmental changes may thus lead to a further population decline, or at the very least will not allow the population to recover. Monitoring the population dynamics of Antarctic seabirds is vital to increase our understanding of climate change-induced changes in polar food webs. [ABSTRACT FROM AUTHOR]

The author of the article actualises the Italian genotext of A.M. Gorky's creativity of the Capri period. Neither before nor after the work of "the Stormy Petrel of the Revolution" was characterised by such a joyful and "spiritually uplifting" worldview as it was on the island of Capri. Despite the fact that Gorky wrote about Russian life, his works of this period reveal an "Italian palimpsest", which became the subject of analysis. Gorky's works Confession (1907-1908), Summer (1909), Gorodok Okurov (1909-1910), The Life of Matvei Kozhemyakin (1910-1911) have not been analysed by researchers from the point of view of the Italian presence. The Italian palimpsest of Gorky's Capri oeuvre was first brought to the attention of one of the first chroniclers of "Russian Capri", the writer Alexei Zolotarev, who pointed out the main peculiarity of this period of the writer's work, which still raises many questions for literary historians. [ABSTRACT FROM AUTHOR]

Investigations into niche dynamics and interspecific interactions are crucial to assess the vulnerability of threatened species to competition and environmental change. The Whenua Hou Diving Petrel Pelecanoides whenuahouensis is a critically endangered seabird, specializing in breeding in sand dunes in Aotearoa (New Zealand). The species is at risk from competition for burrow sites with the abundant, habitat‐generalist Common Diving Petrel Pelecanoides urinatrix chathamensis, among other terrestrial and near‐shore threats (storm‐induced erosion and vessel‐based light pollution). However, Whenua Hou Diving Petrel foraging niches at sea and associated threats are poorly understood. We sampled blood and feathers from both species on Whenua Hou (Codfish Island) during 2017–19 and used stable isotope (δ15N and δ13C) analyses to quantify foraging niche dynamics and interspecific interactions. During incubation periods, when birds are restricted by central place foraging, diving petrels exhibited clear niche segregation. Whenua Hou Diving Petrels were more generalist feeders with wider isotopic niches than Common Diving Petrels, which exhibited restricted isotopic niches and fed in neritic waters. During non‐breeding periods, foraging niches expanded, and segregation was reduced, as both species dispersed into the Southern Ocean. These patterns were largely consistent among years, despite varying climatic conditions. However, Common Diving Petrel foraging niches appeared to shrink during El Niño conditions, suggesting environmental sensitivity. In contrast, the consistently stable, generalist foraging niches of Whenua Hou Diving Petrels suggested potential limited sensitivity to competition and impacts of environmental change at sea. Recovery efforts should, therefore, focus on addressing the previously identified terrestrial and near‐shore threats. [ABSTRACT FROM AUTHOR]

Although literary geography has become an established subfield, to date, there are no in-depth geographical studies on literary groups that gather to celebrate a specific author and/or genre. To address this lacuna, my paper investigates Vancouver's official Sherlock Holmes society, The Stormy Petrels of British Columbia (hereafter Petrels). Drawing on the methods of participant observation and semi-structured interviews, as well as Jacques Lacan's concept of 'le sinthome' (hereafter sinthome), which defines how creative modes of (un)conscious enjoyment knot together psychical and social space, I explore three ways through which the Petrels' enjoyment of Sherlock Holmes gives consistency to their individual and collective lives: first, through 'nomination' wherein the Petrels identify with Sherlockian characters and make names for themselves; second, through what Lacan refers to as 'lalangue,' that is, enigmatic meanings produced by the musical flows and babbles of speech; and third, through the surplus accumulation of memorabilia, what I call 'sintholmes,' which hold a powerful attraction as sublime objects of Sherlockiana. The article concludes by considering the political dimensions of the sinthome in terms of the changes in the Petrels' demographics and the wider context of Sherlock Holmes fandom. [ABSTRACT FROM AUTHOR]

The cape petrel (Daption capense) is an abundant procellariform in seabird assemblages attending fishing vessels in the Southwestern Atlantic Ocean. The bulk of extant information comes from surveys conducted during the breeding season at Antarctic and sub-Antarctic sites; however, most of their ecological aspects during the non-breeding season remain largely unknown. We performed on-board census and stable isotope analysis in blood and feathers from 30 adult petrels during the non-breeding season in waters off Argentina. Cape petrels attending ice trawlers showed a higher abundance during winter compared to other seasons. The lack of correlation of isotopic values between tissues suggests changes in the diet and foraging locations between the moulting period and the non-breeding season. Isotopic mixing models revealed low-trophic-level sources as the main contributors to this petrel's diet while pelagic-demersal fish species targeted by fishing vessels showed the lower contribution. The discrepancies between methods could be a result of partial use of offal/discards or low use of these due to size/mechanic limitations. These findings reinforce the idea of zooplankton and small-pelagic fish facilitation during the hauling operatory and the relevance of combining different methods for a thorough understanding of prey-predator relationships. [ABSTRACT FROM AUTHOR]

Artificial nest chambers have become a common management tool for monitoring nocturnal burrow-nesting seabirds, although their utility varies among species and locations. The widespread Band-rumped Storm Petrel Hydrobates castro species complex potentially harbours a cryptic species endemic to the South Atlantic. Here we evaluate the installation of artificial nest chambers as a tool for long-term conservation and monitoring of this species, which breeds in two distinct seasons on St Helena. Based on six years of observational data, we analysed factors affecting occupancy, mate and chamber fidelity, and reproductive success to optimise nest chamber installation and to enhance future management. Occupancy rates were high, increasing from 5% after the first season following installation to 85% after five years. Occupancy was positively associated with (1) the number of seasons since chamber installation, (2) whether the chamber was occupied in the previous season, and (3) whether the chamber was occupied in the same season in the previous year. Occupancy also varied with chamber location and lid construction material: chambers with wooden lids had 7% lower occupancy and 18% lower breeding success than chambers with other lid types. Lid replacement also negatively affected occupancy. Chamber monitoring revealed that individuals exhibited 93% mate fidelity and 86% chamber fidelity with little effect of previous breeding outcome. From 312 monitored nests, hatching success was 15% higher during the hot season, while fledging success was 28% higher during the cool season, leading to only 3.2% difference in overall productivity between seasons. Fledging success of each seasonal population varied by year. Chick mortality was considerably higher during the hot season (41% compared to 13% during the cool season), possibly reflecting different responses to temperature regime. We conclude that installation of artificial nest chambers represents an effective monitoring tool, and recommendations for the design and management of chambers are discussed. [ABSTRACT FROM AUTHOR]

This note reports observations of a presumed Beck's Petrel Pseudobulweria becki and a Vanuatu Petrel Pterodroma [cervicalis] occulta in April 2022, in the low latitudes of the North Pacific, north of Kiritimati, Republic of Kiribati. The sightings are significant because the ranges of both taxa are barely known and their conservation classifications are concerning. We explain the circumstances of each sighting and the process of identification, reflecting upon current identification criteria and our studies of Beck's Petrel and Vanuatu Petrel at their breeding grounds. Discussion is illustrated with photographs of each bird and its cryptic confusion counterpart--the larger Tahiti Petrel Pseudobulweria rostrata for Beck's Petrel, and the larger White-necked Petrel Pterodroma cervicalis for Vanuatu Petrel. These two confusion pairs are generally considered inseparable at sea, but we demonstrate otherwise, given favourable circumstances. [ABSTRACT FROM AUTHOR]

Population trends of seabirds nesting on Kaua'i in the Hawaiian Islands, USA, were assessed across four decades using data from the Save Our Shearwaters (SOS) program. Started in 1979, the SOS database was intended to track the incidence of attraction of Kaua'i's seabirds to artificial lights, but recovery rate data also became useful to index population trends. These data documented precipitous declines of Newell's Shearwater Puffinus newelli through 2017. Here we expand on those efforts by including four additional species and consider data to 2018. All five species exhibited increasing trends during SOS's first decade, coincidental with increasing human population, suburban infrastructure, and public awareness. Counts of the once-numerous Newell's Shearwater decreased sharply beginning in the late 1980s, but stabilized around 2012. Since that approximate time, counts of Wedge-tailed Shearwater Ardenna pacifica and White-tailed Tropicbird Phaethon lepturus have increased. Conversely, counts of Hawaiian Petrel Pterodroma sandwichensis and Band-rumped Storm Petrel Hydrobates castro have remained stable since 1990. The implications of sizable decreases in a population are rarely considered from a community ecology perspective, but in this case, such an examination is possible: the decline of Newell's Shearwater may have led to a competitive release of trophic resources and nesting habitat, benefitting Wedge-tailed Shearwaters and White-tailed Tropicbirds, respectively. We also explore other issues potentially explaining observed trends. Clearly the SOS program is an important contributor to the success of both seabird conservation, by rehabilitating seabirds grounded by artificial lights, and management, by documenting long-term population changes that would have otherwise been unknown. [ABSTRACT FROM AUTHOR]

Population declines of Leach's Storm Petrels Hydrobates leucorhous in the western Atlantic have both led to the species' recent assessment as Threatened in Canada and contributed to a Vulnerable designation by the IUCN. Limited information suggests low adult survival rates are an important contributing factor. Off eastern Nova Scotia, Canada, Country Island is managed for avian predators and mustelids to protect nesting endangered Roseate Terns Sterna dougallii. The island also hosts a colony of Leach's Storm Petrels. In 2016, a capture-markrecapture program was initiated for storm petrels, from which we estimated apparent survival and recapture probabilities for 571 breeding birds using data collected from 2016 to 2021. Models with a time-since-marking effect were consistently ranked higher than those without; annual apparent survival estimates in the first year after capture were lower than in subsequent years, presumably due to some captured birds not returning to the study area. Apparent survival in the years subsequent to first capture was lowest in forested areas with no understorey vegetation, slightly higher in forested areas with fern understorey, and highest in open areas with dense fern cover. While the mechanism driving habitat differences in adult survival is unknown, predation pressure may be strongest in forested areas with open understorey where it is easier for predators to find burrow entrances. Although apparent adult survival rates were higher than reported previously for nearby Bon Portage Island where predation is significant, Country Island may represent a best-case scenario for Leach's Storm Petrel in Atlantic Canada, since predators are managed and adult mortality from avian predators is relatively low at this site. Even so, survival rates at Country Island are lower than those reported previously at two Pacific colonies and provide evidence that adult survival rates of Leach's Storm Petrels in eastern Canada are depressed. [ABSTRACT FROM AUTHOR]

Many animals are highly adapted to cover vast distances in search of ephemeral food resources. Pelagic seabirds have particularly wide-ranging foraging trips, made possible through efficient use of wind. During incubation, partners alternate long periods of fasting and so should adjust foraging and flight decisions according to the condition of the pair, as well as wind conditions experienced at sea. Here, we tracked incubating Juan Fernández petrels, Pterodroma externa , with GPS and immersion loggers, assigned at-sea behaviours using hidden Markov models, and weighed birds and their partners, to investigate the roles of wind and mass on flight and foraging behaviour, and the link between wind use and trip success. Birds conducted long anticlockwise looping trips, on average lasting 20.4 days and covering 10 741 km. They reached a region in the southeastern Pacific Ocean where prey search behaviour was concentrated, typically about 3400 km west of the colony. Outbound and return journeys appeared to broadly benefit from predictable southeasterly trade and westerly winds, respectively. Over finer scales, departure bearings were influenced by wind directions. Across trips, birds oriented predominantly with quartering tail winds which maximized ground speeds. Individuals experienced variable support from tail winds, and those that benefited more on outbound journeys (when winds were generally weaker) travelled faster, reached foraging areas more quickly and, over the entire trip, had higher mass gain per day at sea. Additionally, birds that were lighter on departure gained more mass and birds with heavier partners ranged further from the colony. Our results suggest that decisions involving where to go and how far, respectively, are based on prevailing wind patterns and an assessment of the condition of the pair. Consequently, while birds sought to benefit from wind assistance, those encountering greater tail wind support had more successful foraging trips, indicating that wind use may have direct fitness consequences. • Gadfly petrel foraging trips covered > 10 000 km in the southeast Pacific. • Birds maximized ground speeds by orienting with tail or cross-winds on an ocean scale. • Birds more aided by tail winds reached foraging areas quicker and gained more mass. • Lighter birds gained more mass and birds with heavier partners ranged further. • Wind and pair condition influenced foraging destinations and trip success. [ABSTRACT FROM AUTHOR]

Snow petrels (Pagodroma nivea), which are endemic to the Antarctic region, produce proventricular stomach oil from ingested food for feeding purposes but also spit the oil in the immediate surrounds of the nests, where it forms encrustations over time (Antarctic mumiyo). These deposits provide a unique opportunity to understand the paleo‐ecological diet of snow petrels and because the seabirds forage in the ocean, they potentially provide an archive of past marine environmental conditions in the Southern Ocean. For validating methods for reconstructions we use compositional data obtained on modern stomach oils and DNA data from fecal samples of snow petrels. We find that the distribution of carboxylic acid compounds in modern stomach oils and in the fossil deposits are consistent with variable contributions of fish and krill, which are the main constituents of modern snow petrel diet, and allows inference of past changes in snow petrel diet from the fossil record. Analyses of mumiyo deposits from six regions in East Antarctica reveal systematic differences in the isotopic composition of organic matter (δ13C and δ15N) and carboxylic acid patterns. This may suggest regional and/or temporal variability in the composition of snow petrels diet, likely differing in response to the prevailing environmental conditions in the foraging range of the birds, such as sea‐ice variability, polynya activity and primary productivity. Our study provides confidence for using these approaches for broader scale paleo‐studies in the future and for an assessment of the temporal changes and regional variability in snow petrel diet. Plain Language Summary: To better understand interactions of biological and physical processes in Antarctic marine ecosystems, we investigate fossil deposits of stomach oil of snow petrels for their use as a geological archive for past environmental changes. The deposits form over time in the surroundings of the nesting cavities of snow petrels, which produce stomach oil from ingested food but also spit it at nest robbers. In fresh oil the lipid and isotopic composition can be traced back to the composition of snow petrel food, such as variable proportions of fish and krill. From comparing the lipid and δ13C‐isotopic composition of modern oil to fossil deposits we suggest it is possible to identify changes in the diet of snow petrels in the fossil record. Since the composition of the diet is closely linked to the prevailing environmental conditions in the marine foraging region of the birds, such as summer sea ice extent, this information can be used for paleoenvironmental reconstructions. Our study of deposits from widely separated regions in Antarctica shows that there are spatial and temporal differences in the composition of stomach oil deposits, likely related to the prevailing environmental conditions. This finding underpins the application of our approach. Key Points: Modern stomach oil and feces of snow petrels are used to validate paleo‐proxies for environmental reconstructions in East AntarcticaBiomarkers and isotopic composition of fossil stomach oil deposits of snow petrels reflect past composition in dietChanges in the composition of the paleo‐ecological diet reflect variations of environmental conditions in the coastal Southern Ocean [ABSTRACT FROM AUTHOR]

Foraging niche specialization is thought to occur when different members of speciose communities divide resources in either time or space. Here we compared habitat preferences of the congeneric Grey Petrel Procellaria cinerea and White‐chinned Petrel Procellaria aequinoctialis, tracked in the same calendar year using GPS loggers from Gough Island and Bird Island (South Georgia), respectively. We identified periods of active foraging and determined habitat characteristics using remote‐sensing data. Although these highly pelagic species could potentially overlap at sea across large areas, they showed markedly different foraging preferences during their incubation periods, which are temporally offset because Grey Petrels breed during the austral winter. Grey Petrels foraged mostly in pelagic cold‐water areas to the north‐west of South Georgia, whereas White‐chinned Petrels foraged almost exclusively in the warm, shallow waters of the Patagonian Shelf. Within each species, foraging habitat characteristics were highly consistent. Our results demonstrate the diversity of habitat preferences within genera, and provide further evidence that colony‐specific information on habitat preference is crucial to identify important feeding areas for pelagic predators. [ABSTRACT FROM AUTHOR]

Cover image: European storm petrel Hydrobates pelagicus feeding on the discards generated by the trawl fleet in the waters of the Atlantic Iberian arc. (pp. 2586–2601).Photo: © Andrés de la Cruz. [Extracted from the article]