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The status of 37 species of breeding seabirds in Japan has been reported by Hasegawa(1984). However, since then, no report has been made. The author was involved in the launch of seabird monitoring for the Monitoring site 1000 project by the Ministry of the Environment in 2004. In the over 15 years since then, population and habitat have been surveyed in 30 major breeding areas, including 80 islands and islets in Japan. In this paper, the previous studies including reports based on this project and the seabird colony database were reviewed. The populations of many species at various islands declined, possibly because of introduced predators and human disturbance. The nesting habitats of most of the seabird breeding areas had deteriorated. Therefore, the continuous monitoring of the change of the population and nesting habitat and quick operation of appropriate conservation measures, eradication of introduced predators and redacation of human disturbance)are required. In this paper, 1)distribution of seabirds, 2)monitoring seabird survey, 3)current status, 4)introduced predators, and 5)conservation activities are summarized. Further 1)necessity of long-term monitoring of seabirds, 2)extermination of introduced predators, 3)reduction of anthropogenic disturbances, and 4)issues of conservation measures are discussed. [ABSTRACT FROM AUTHOR]

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Species reliant on both the terrestrial and marine realms present a challenge for conventional species distribution models (SDMs). For such species, standard single‐realm SDMs may omit key information that could result in decreased model accuracy and performance. Existing approaches to habitat suitability modeling typically do not effectively combine information from multiple realms; this methodological gap can ultimately hamper management efforts for groups such as seabirds, seals, and turtles. This study, for the first time, jointly incorporates both terrestrial information and marine information into a single species distribution model framework. We do this by sampling nearby marine conditions for a given terrestrial point and vice versa using parameters set by each species' mean maximum foraging distance and then use standard SDM methods to generate habitat suitability predictions; therefore, our method does not rely on post hoc combination of several different models. Using three seabird species with very different ecologies, we investigate whether this new multi‐realm approach can improve our ability to identify suitable habitats for these species. Results show that incorporating terrestrial information into marine SDMs, or vice versa, generally improves model performance, sometimes drastically. However, there is considerable variability between species in the level of improvement as well as in the particular method that produces the most improvement. Our approach provides a repeatable and transparent method to combine information from multiple ecological realms in a single SDM framework. Important advantages over existing solutions include the opportunity to, firstly, easily combine terrestrial and marine information for species that forage large distances inland or out to sea and, secondly, consider interactions between terrestrial and marine variables. [ABSTRACT FROM AUTHOR]

1. Individual specialisations in behaviour are predicted to arise where divergence benefits fitness. Such specialisations are more likely in heterogeneous environments where there is both greater ecological opportunity and competition-driven frequency dependent selection. 2. Such an effect could explain observed differences in rates of individual specialisation in habitat selection, as it offers individuals an opportunity to select for habitat types that maximise resource gain while minimising competition; however, this mechanism has not been tested before. 3. Here, we use habitat selection functions to quantify individual specialisations while foraging by black-legged kittiwakes Rissa tridactyla, a marine top predator, at 15 colonies around the United Kingdom and Ireland, along a gradient of environmental heterogeneity. 4. We find support for the hypothesis that individual specialisations in habitat selection while foraging are more prevalent in heterogeneous environments. This trend was significant across multiple dynamic habitat variables that change over short time-scales and did not arise through site fidelity, which highlights the importance of environmental processes in facilitating behavioural adaptation by predators. 5. Individual differences may drive evolutionary processes, and therefore these results suggest that there is broad scope for the degree of environmental heterogeneity to determine current and future population, species and community dynamics. [ABSTRACT FROM AUTHOR]

Great Cormorants Phalacrocorax carbo sinensis are considered generalist predators feeding in a variety of marine and freshwater habitats on many different prey species. Recently however, there is increasing evidence that even seemingly generalist species can often be regarded as a diverse group of individual specialists sometimes induced by sex-specific foraging behaviour. To test whether this also holds true for Great Cormorants, the present study characterised the at-sea distribution and examined the time budgets of provisioning Great Cormorants by deploying GPS-loggers on 11 nesting males and females during the breeding season of 2012. Additionally, pellets were collected from underneath the nests of these tagged birds for detailed diet analysis, based on the otoliths and fish bones recorded within them. Diverse foraging patterns were recorded, ranging from exclusively freshwater feeding, to offshore foraging, with the furthest recorded distance from the colony being 28 km at sea. Time budgets during foraging trips revealed relatively long periods of resting ashore (55% of the trip ± 23%), followed by foraging (31 ± 18%), and time spent in flight (15 ± 11%). Flatfishes dominated in the diets of these Great Cormorants, indicating benthic-foraging strategies when foraging in saltwater (feeding on discards could be ruled out). The males in this study avoided freshwater foraging habitat and preferred offshore waters with a sandy bottom or nearshore waters alongside rocky breakwaters and within harbours. Females foraged in all habitat types, but proportionally more in inland freshwater bodies. Females spent more time on foraging than did males, particularly in marine habitats, whilst males rested more. It is proposed that these differences might have been caused by sex-specific foraging strategies, possibly resulting from competition at foraging sites. [ABSTRACT FROM AUTHOR]

The nest site characteristics of two endangered seabird species–the Hawaiian Petrel Pterodroma sandwichensis and Newell's Shearwater Puffinus newelli–on Kaua'i were considered. Burrows of both species were predominantly found under tree roots or small caves on steep slopes and were associated with native plants, both in the canopy (particularly Metrosideros polymorpha) and the understory (particularly Dicranopteris linearis). There were, however, marked differences between the two species. Hawaiian Petrels were found at higher elevations with a shorter, patchy canopy and more open understory. Models using microhabitat variables were better able to classify burrows than those using landscape topographic metrics, suggesting that metrics describing the immediate area around the burrow are more important to burrow selection. A comparative model indicated that elevation and maximum vegetation height were the strongest variables in classifying between the two species. Understanding microhabitat needs for these species is important for locating new colonies and for the successful implementation of management actions such as colony creation through social attraction. Furthermore, with the spread of Rapid'Ōhi'a Death canker disease Ceratocystis huliohia on Kaua'i, the heavy reliance by both species on forest dominated by M. polymorpha (the tree killed by this disease) should be of increasing consideration for conservation efforts targeting these species. [ABSTRACT FROM AUTHOR]

Heterospecific disturbance in seabird colonies can negatively influence reproductive success both through direct effects, such as predation, and through indirect effects, such as increasing parental energy expenditure via defense behaviors. Here, remote nest cameras were used to evaluate the effects of intrusion on early nest survival and predation risk in Roseate Tern (Sterna dougallii) colonies in the U.S. and British Virgin Islands. Effects of colony traits such as colony size on parental nest defense were also investigated to assess individual response to predator presence in colonies. We counted 141 intrusion events at 118 nests and found that frequency of heterospecific disturbance did not influence nest survival, but did have a positive association with predation rate. Disturbance decreased significantly with colony size and % cover, and disturbance increased with nest density, indicating that concealed, isolated nests within large colonies were less likely to be disturbed. Parental nest defense decreased significantly with colony size and nest density. Results were likely driven by the dominant predator types in our system—large predatory birds and invasive rats—as parents were more likely to leave nests with intrusion from these predator types. [ABSTRACT FROM AUTHOR]

Summary: The Black-capped Petrel or Diablotin Pterodroma hasitata has a fragmented and declining population estimated at c.1,000 breeding pairs. On land, the species nests underground in steep ravines with dense understorey vegetation. The only confirmed breeding sites are located in the mountain ranges of Hispaniola in the Caribbean, where habitat loss and degradation are continuing threats. Other nesting populations may still remain undiscovered but, to locate them, laborious in situ nest searches must be conducted over expansive geographical areas. To focus nest-search efforts more efficiently, we analysed the environmental characteristics of Black-capped Petrel nesting habitat and modeled suitable habitat on Hispaniola using openly available environmental datasets. We used a univariate generalized linear model to compare the habitat characteristics of active Black-capped Petrel nests sites with those of potentially available sites (i.e. random pseudo-absences). Elevation, distance to coast, and the influence of tree cover and density emerged as important environmental variables. We then applied multivariate generalized linear models to these environmental variables that showed a significant relationship with petrel nesting activity. We used the top performing model of habitat suitability model to create maps of predicted suitability for Hispaniola. In addition to areas of known petrel activity, the model identified possible nesting areas for Black-capped Petrels in habitats not previously considered suitable. Based on model results, we estimated the total area of predicted suitable nesting habitat for Black-capped Petrels on Hispaniola and found that forest loss due to hurricanes, forest fires, and encroachment from agriculture had severely decreased availability of predicted suitable habitat between 2000 and 2018. [ABSTRACT FROM AUTHOR]

Many animal populations include a diversity of personalities, and these personalities are often linked to foraging strategy. However, it is not always clear why populations should evolve to have this diversity. Indeed, optimal foraging theory typically seeks out a single optimal strategy for individuals in a population. So why do we, in fact, see a variety of strategies existing in a single population? Here, we aim to provide insight into this conundrum by modelling the particular case of foraging seabirds, that forage on patchy prey. These seabirds have only partial knowledge of their environment: they do not know exactly where the next patch will emerge, but they may have some understanding of which locations are more likely to lead to patch emergence than others. Many existing optimal foraging studies assume either complete knowledge (e.g. Marginal Value Theorem) or no knowledge (e.g. Lévy Flight Hypothesis), but here we construct a new modelling approach which incorporates partial knowledge. In our model, different foraging strategies are favoured by different birds along the bold-shy personality continuum, so we can assess the optimality of a personality type. We show that it is optimal to be shy (resp. bold) when living in a population of bold (resp. shy) birds. This observation gives a plausible mechanism behind the emergence of diverse personalities. We also show that environmental degradation is likely to favour shyer birds and cause a decrease in diversity of personality over time. [ABSTRACT FROM AUTHOR]

In many socially monogamous species, divorce is a strategy used to correct for sub-optimal partnerships and is informed by measures of previous breeding performance. The environment affects the productivity and survival of populations, thus indirectly affecting divorce via changes in demographic rates. However, whether environmental fluctuations directly modulate the prevalence of divorce in a population remains poorly understood. Here, using a longitudinal dataset on the long-lived black-browed albatross (Thalassarche melanophris) as a model organism, we test the hypothesis that environmental variability directly affects divorce. We found that divorce rate varied across years (1% to 8%). Individuals were more likely to divorce after breeding failures. However, regardless of previous breeding performance, the probability of divorce was directly affected by the environment, increasing in years with warm sea surface temperature anomalies (SSTA). Furthermore, our statespace models show that warm SSTA increased the probability of switching mates in females in successful relationships. For the first time, to our knowledge, we document the disruptive effects of challenging environmental conditions on the breeding processes of amonogamous population, potentially mediated by higher reproductive costs, changes in phenology and physiological stress. Environmentally driven divorce may therefore represent an overlooked consequence of global change. [ABSTRACT FROM AUTHOR]

Breeding at the right time is essential for animals living in seasonal environments to ensure that energy requirements for reproduction, especially the nutritional needs for rearing offspring, coincide with peak food availability. Climate change is likely to cause modifications in the timing of maximum food availability, and organisms living in polar environments where the breeding period is heavily contracted may be particularly affected. Here we used a 26-year dataset to study the phenological response of a pagophilic species, the Snow Petrel (Pagodroma nivea), to climate change and its demographic impact. First, we investigated the trends and relationships between climate variables and hatching dates measured in three neighboring colonies. In a second step, we examined the impact of the hatching date and environmental covariates on the fledging probability. Our results showed that sea ice, a climate-related variable, showed a positive temporal trend. We found that hatching date was delayed when sea ice concentration was greater and local weather conditions were worse (i.e., increase in the number of windy days or the number of snow days). Hatching date had a negative effect on fledging probability, and fledging probability showed a bell-shaped temporal trend. We suggest that Snow Petrels can delay breeding phenology in response to environmental conditions. However, this plasticity may be limited as fledging success decreased with delayed hatching, potentially making the Snow Petrel vulnerable to a mismatch between resource availability and nutritional needs. [ABSTRACT FROM AUTHOR]

Despite intensive management since the 1970s, recovery of the endangered northwestern Atlantic population of the Roseate Tern (Sterna dougallii dougallii) has not offset low productivity from a female-biased sex ratio, low adult survival, and habitat constriction. Now, >90% of individuals breed at three sites within 200 km from Long Island, NY, to Buzzards Bay, MA (warm-water subregion). To characterize the impact of historical bottlenecks, metapopulation structure, and demographic fluctuations on genetic variation, Roseate Terns from the warm-water (1870s, 1970s, 1997, 2016) and coldwater (Nova Scotia, Canada; 2018) subregions were genotyped at 8-16 microsatellites and 2-3 mitochondrial regions. Diversity declined in the warm-water subregion from the 1870s (expected heterozygosity [HE] = 0.44, allelic richness [AR] = 2.86) and 1970s (HE = 0.53, AR = 3.25) to 1997 (HE = 0.38, AR = 2.58). Genetic signatures of bottlenecks persisted in 1997 (P = <0.001-0.003) and 2016 (P = <0.001-0.005), but an increase in variation occurred by 2016 (HE = 0.50, AR = 2.85). Weak structure was detected between contemporary warm- and cold-water subregions (θ = 0.06) and within the warmwater subregion (θ = 0.04). Both demographic (3,439-3,821) and genetic (3,040) estimates suggested effective population size (Ne) stability over the last 100 years, despite large fluctuations in census size (4,000-8,662). Results suggest that 50 years of management (restoring habitat, preventing gull encroachment, controlling predators) at colony sites supported a small, stable Ne and maintained a hierarchical metapopulation that allowed gene flow to redistribute genetic variation throughout the northwest Atlantic. The metapopulation remains highly vulnerable to stochastic events but harbors resiliency and redundancy through gene flow and a stable Ne. For long-term persistence from a genetic perspective, managers must maintain the major source colonies, increase the availability of high-quality peripheral breeding sites, and protect concentrated nonbreeding sites that facilitate gene flow. [ABSTRACT FROM AUTHOR]

The Arctic is currently experiencing the most rapid warming on Earth. Arctic species communities are expected to be restructured with species adapted to warmer conditions spreading poleward and, if already present, becoming more abundant. We tested this prediction using long‐term monitoring data (2009–2018) from nine of the most common seabird species breeding in the High Arctic Svalbard archipelago. This region is characterized by rapidly warming ocean temperatures, declining sea‐ice concentrations and an increasing influence of Atlantic waters. Concurrent with these environmental changes, we found a shift in the Svalbard seabird community, with an increase in abundance of boreal species (defined here as species breeding commonly in temperate environments) and a decline in Arctic species (species breeding predominantly in the Arctic). Combined with previous observations from lower trophic levels, our results confirmed that part of the Arctic fauna is moving from an arctic to a boreal (or north temperate) state, a process referred to as a "borealization." Spatial variations exist among colonies for some species, indicating that local conditions may affect the trajectories of specific populations and potentially counterbalance the consequences of large‐scale climate warming. [ABSTRACT FROM AUTHOR]

Primary producers are the foundation of marine food webs and require reliable nutrient sources to maintain their important role with ecosystems. While marine mammals and seabirds can play critical roles in marine nutrient cycling, their contributions are often overlooked. Southeast Alaska’s marine environment supports abundant marine mammal and seabird populations in addition to valuable fisheries. Nonetheless, there is still relatively little known about nutrient sources and fluxes in this region which is a critical component of fisheries management. The goal of our study was to advance knowledge of the role of mammals and seabirds in marine nutrient cycling and to understand how changing marine mammal and seabird populations may alter ecosystem dynamics. We utilized qualitative network models (QNMs) to examine how a simulated Southeast Alaska ecosystem would respond to an increase in marine mammals, seabirds, and nutrients. Researchers are increasingly utilizing QNMs as a first step in the development of ecosystem-based fisheries management plans as their adaptable nature is well suited to address rapidly changing climatic conditions. Our results indicate that marine mammals and seabirds make important contributions to marine nutrient concentrations in the region and that these valuable ecosystem services should not be overlooked.

We present an integrative statistical approach for estimating the current conditions of marine-bird habitats affected by human activities. We first estimated the influence of multiple human offshore activities on the species of interest using integrative regression techniques. We then used these models to predict the distribution and abundance of the species throughout the study area, in both the current situation, with human activities, and in a hypothetical situation without the effects of the studied human activities. We finally developed different measures related to the comparison between these two scenarios. The presented approach allows the integration of bird-count data from different sources and sampling schemes, thus maximizing the underlying database. It also provides a local metric highlighting critical regions where locally high abundance is co-localized with large declines in abundance due to human activities, as well as a global metric quantifying the overall condition of the marine-bird habitat in the study area in relation to human disturbance. This approach allows us to assess the cumulative influence of several anthropogenic pressures. We exemplarily applied the above approach to four different species and two different sea regions, namely European herring gulls and long-tailed ducks in the German section of the Baltic Sea, and European herring gulls, red-throated loons, and common murres in the German–Dutch–Belgian part of the North Sea. The considered activities were offshore wind farms, bottom-trawling fishery, and ship traffic. The results confirmed the avoidance of and attraction to human activities by marine bird species found in previous studies. These results show that the methods developed here can be used to provide indicators for inclusion in bird assessments under OSPAR and HELCOM conventions, and MSFD Article 8, criterion D1C5 (habitat for the species). The resulting indicator can be used to inform programmes of measures under MSFD Article 13.

The ʻuaʻu, or Hawaiian Petrel, Pterodroma sandwichensis, is an endangered seabird endemic to the Hawaiian Islands. Although its distribution on some of the islands is well documented, on larger islands such as Hawaiʻi there are significant distribution gaps. Previous work within the Puʻu O ʻUmi Natural Area Reserve (NAR) on Hawaiʻi strongly suggested that a breeding colony of the species was present, but active burrows had not been located making it difficult to focus management actions. Searching for burrows of this nocturnal burrow-nesting seabird had been particularly challenging in the NAR, as the birds are very rare, widely dispersed, and breeding in remote areas with dense vegetation and challenging topography. To locate active burrows, we employed the use of tracking devices to track breeding adults back to their burrows. Six data loggers (e-obs Bird Solar 10g) were attached to transiting birds caught using lights in 2018 and 2019. Overland locational data was then interrogated for concentrated areas of circling and ground activity. This resulted in several areas of concentrated activity and two different locations where tracked birds ended up transmitting from the ground. Burrow searching teams were then deployed to these areas and an active Hawaiian Petrel burrow was located. This represents the first active burrow ever documented in the NAR and the entirety of Kohala Mountain. Management actions have since been initiated to protect birds breeding within the areas defined by our tracking data. Logistical and methodological considerations inherent in the use of telemetry for locating endangered seabird colonies are discussed.

Multi-species feeding associations (MSFAs) are temporary communities of animals exploiting the same or co-occurrent resources. Their dynamics are species dependent, often creating competitive interactions, but they can also increase foraging efficiency and ultimately individual fitness. The foraging behaviors of some species can enhance prey capture by others, with different roles depending on the species present. Here, we use the Hauraki Gulf, New Zealand, as a model system to quantitatively characterize the principal types of MSFAs between 2011 and 2020. We determine the foraging associations of a large generalist predator, the Bryde’s whale, and how shifts in its prey preference change the dynamics between seabird competitors. Hierarchical clustering from influential predator groups identified three types of MSFAs. Two of mainly fish-feeding predators, one including and one lacking Bryde’s whales, and one involving (although not limited to) plankton-feeders associated with Bryde’s whales. Cluster frequencies featured significant temporal trends, whereas MSFA diversity and whale association rate showed no significant changes. Bryde’s whales’ increasing reliance on zooplankton highlights their foraging plasticity, with changes in cluster frequencies and resource competition related to this shift from fish to zooplankton. The role of Bryde’s whales varies from joiners and terminators in fish-feeding aggregations to initiators with plankton-feeding seabird associations, thereby changing the MSFA dynamics. MSFAs tend toward a diversity equilibrium, i.e., a maximum number of species involved before competitive effects exceed the benefits of interaction. Functional MSFAs where heterospecific interactions are important to foraging success can be affected by changing composition. Future work should focus on the behavioral interactions between key predators, prey availability and their effect on MSFAs.

Biodiversity conservation is limited by resources, data, and time for execution. To maximize efficacy, it is best if conservation plans are strategically evaluated for cost, feasibility, and likely impact prior to implementation. We present a framework to systematically examine the likely impact of proposed conservation plans for threatened taxa. As a case study of this framework we use the national Action Plan for Seabird Conservation in New Zealand and 27 threatened seabirds identified for conservation interventions. To evaluate impact, we applied a recently developed seabird meta-population viability analysis model (seabird mPVA) that employs the most current population and adjustable demographic data to assess threatened seabird viability at a global scale under various management scenarios. This publicly available, web-based tool is intended to meet the needs of threatened seabird managers at the initial phase of conservation planning. We used the seabird mPVA to model population trends and potential seabird viability gains from conservation actions that include: bycatch mitigation, invasive species removal, and seabird translocation prescribed in the action plan for individual species. Our model’s ranking of New Zealand seabirds by current quasi-extinction vulnerability roughly correlated with the seabirds’ IUCN Red List status and New Zealand Threat Classification System. We found modeled conservation impact of proposed actions and assigned priority to be generally positively correlated, but variable in magnitude. If all prescribed conservations actions were implemented, our model predicted significant mitigation of quasi-extinction risk for nine species (Antipodean Albatross, Auckland Island Shag, Black-fronted Tern, Fairy Tern, Rough-faced Shag, Northern Royal Albatross, Pitt Island Shag, Stewart Island Shag, Yellow-eyed Penguin). This approach, and our model, can be adapted to other taxonomic groups to provide a consistent framing for the prioritization of species for conservation investment and predictions about the benefits of specific conservation actions for those species.

Egg laying is one of the most important phases in a female bird's breeding cycle. Its cost is high because eggs contain all the resources needed for the development of an embryo. Variation in size and quality of eggs can have important long‐term consequences for offspring survival. Hatching asynchrony is known to influence sibling competition in many bird species. Last‐hatched chicks will have a competitive disadvantage throughout the pre‐fledgling period because they are smaller. The aim of this study was to analyze the effect of hatching asynchrony and egg size variation on the growth and fledging success of Magellanic penguin Spheniscus magellanicus chicks after disentangling the effects of parental condition. We simultaneously manipulated egg size dimorphism, hatching asynchrony and parental condition by performing a cross‐fostering experiment, creating broods with controlled egg size dimorphism and hatching asynchrony in a colony of Magellanic penguins located in Isla Quiroga, Santa Cruz, Argentina. We found that hatching asynchrony had a negative effect on last‐hatched chicks, but this disadvantage was mitigated by egg size dimorphism in their favor. Moreover, females in good condition invest more in second than in first chicks, which, added to a greater investment by foster fathers, leading to offspring fledging in good condition. On the contrary, for the first‐hatched chicks, we found that body condition of the biological father was an important factor for their growth. We conclude that raising more than one chick seems to be a decision based on parental condition throughout the breeding season. [ABSTRACT FROM AUTHOR]

Feathers play an important role in many aspects of avian ecology, including sexual selection, thermoregulation and flight. However, several external stressors can negatively impact plumage condition. Birds preen their feathers to maintain feather integrity throughout the year. For seabirds, preening is especially important to ensure waterproofing of the plumage. However, due to the difficulty of observing seabirds at sea, little is known of the time and energy expended in preening and how this may impact other activities in these species. In the present study, bird-borne video and tri-axial accelerometer data loggers were used to investigate preening in Australasian Gannets (Morus serrator) from two colonies in south-eastern Australia. Gannets spend a substantial proportion of their time at sea preening (25.5 ± 1.7%). No significant differences in preening activity were observed between the 3 years of study or between colonies. Average Vectorial Dynamic Body Acceleration (VeDBA, a proxy for energy expenditure) was significantly higher during preening (0.34 ± 0.02 g) than resting (0.25 ± 0.02 g), but less than for flying or foraging. These results highlight the importance of preening in terms of time and energy in this species. Furthermore, a positive relationship between the number of dives and at-sea preening suggests a negative impact of diving on plumage integrity and, thus, a potential additional time and energy constraint during periods of reduced food availability. [ABSTRACT FROM AUTHOR]

A colony of about 30 000 pairs of Black-tailed Gull Larus crassirostris nest on Kabushima (Kabu Island), which is located on the northeast mainland coast of Japan (Sanriku Coast, Honshu Island). There, the surface-water Hg concentration is higher than in the North Pacific Ocean. We collected carcasses from the breeding colony to assess the level of mercury (Hg) contamination. We measured Hg concentrations in 10 body tissues, including the endocrine glands. The relative mercury concentrations in the tissue samples (µg/g dry weight) were as follows: adrenal glands > livers > kidneys > blood > pituitaries > gonads > breast muscles > thyroid glands > pancreases > brain stems. Correlations existed between blood mercury levels and all body tissues except for the adrenal glands. Based on these results, we suggest that mercury levels in blood may not be a good indicator for hypothalamic-pituitary-adrenal axis impacts in Black-tailed Gulls. [ABSTRACT FROM AUTHOR]

The relative importance of gene flow, genetic drift, and natural selection in driving genetic divergence of local populations, as well as the factors that disrupt gene flow in natural populations, are uncertain. Comparative analyses enable us to test explicit hypotheses regarding the roles of these factors. Gannets (Morus spp.) include three morphologically and ecologically similar seabird species: the Cape Gannet M. capensis, which breeds in southern Africa; the Australasian Gannet M. serrator, which breeds in southeastern Australia and New Zealand; and the Northern Gannet M. bassanus, which breeds in the North Atlantic. We assessed the extent of differentiation in mitochondrial control region sequences and morphometrics among colonies of each species to test mechanisms of divergence. No evidence was found for introgression of mitochondrial DNA between Cape and Australasian gannets, despite the existence of mixed-species pairs, consistent with their taxonomic status as biological species. Significant population differentiation, both in control region sequences and in morphology, was found within both Australasian and Northern gannets. Analyses based on coalescent theory indicated that little to no female-mediated gene flow occurs either between Australasian Gannets in Australia versus New Zealand, or between Northern Gannets in Canada versus Europe. Divergence of these regional populations, as well as Cape versus Australasian gannets, appears to pre-date the Pleistocene glaciations and corresponds to differences in non-breeding distributions. Northern and Australasian gannets may each represent at least two management units for conservation, but additional data are needed on nuclear DNA variation in individuals sampled from more colonies to confirm this result. [ABSTRACT FROM AUTHOR]

In colonial seabirds, the nest substrate that is available and, in particular, the vegetation cover around the nest, are important environmental factors that drive an individual's nesting selection process and, ultimately, reproductive performance. Using data collected during three consecutive years in a Yellow-legged Gull Larus michahellis colony from the Bay of Biscay, Spain, we tested whether clutch size, egg volume, and hatching success covaried with the proportion of vegetation cover around nests. We found no effect of vegetation cover on breeding performance. Laying date showed a positive effect on egg volume and a negative effect on hatching success and the number of hatched eggs. Egg volume tended to be smaller in 2020 compared to 2018 and 2019, and hatching success decreased through the sampling period, with the lowest hatching success occurring in 2020. Our findings agree with a previous study in which vegetation had no or unclear effects on breeding performance in Yellow-legged Gulls; however, they contradict other seabird studies that found a positive correlation between the two variables. The role of vegetation on breeding performance could vary not only between gull species, but also geographically, with ecological drivers such as intra- and interspecific interactions and climate playing key roles in observed differences. Finally, the use of egg volume and hatching success as proxies for breeding output could be used for the long-term monitoring of the relationship between breeding performance and factors such as landfill management, fishing, or climate change in the Yellow-legged Gull and other gull species. [ABSTRACT FROM AUTHOR]

The use of miniaturized electronic tracking devices has illuminated our understanding of seabird distributions and habitat use, and how anthropogenic threats interact with seabirds in both space and time. To determine the year‐round distribution of adult Campbell albatross (Thalassarche impavida), a single‐island endemic, breeding only at Campbell Island in New Zealand's subantarctic, a total of 68 year‐long location data sets were acquired from light‐based geolocation data‐logging tags deployed on breeding birds in 2009 and 2010.During the incubation and chick‐guard phases of the breeding season, birds used cool (<10°C) waters over the Campbell Plateau, but also ranged over deeper, shelf‐break and oceanic waters (4,000–5,500 m) beyond the Plateau. Later in the breeding season, during post‐guard chick‐rearing, Campbell albatrosses exploited generally deep waters (4,000–5,000 m) beyond the Campbell Plateau.During the non‐breeding period, adults tended to move northwards into warmer (approximately 15°C) waters and occupied areas beyond western Australia in the west to offshore from Chile in the east. Overall, about 30% of adults spent some of their non‐breeding period in the central and eastern Pacific Ocean, substantially expanding the previously reported range for this species.One bird, that failed in its breeding attempt in October 2009, departed Campbell Island and circumnavigated the southern oceans before being recaptured back at Campbell Island in October 2010. This is the first example of an annually‐breeding albatross species completing a circumnavigation between breeding attempts.Overlap with fishing effort, using data from the Global Fishing Watch database, was assessed on a monthly and seasonal basis. Generally, levels of overlap between Campbell albatross and fishing effort were relatively low during the breeding season but were approximately 60% higher during the non‐breeding period, underlining the need for international initiatives to safeguard this species. [ABSTRACT FROM AUTHOR]

The conservation of migratory species poses significant challenges that may be countered by detailed knowledge about the sites used by migrants throughout the annual cycle. We present the first GPS‐tracking data on the migration of declining Caspian terns Hydroprogne caspia breeding in the Baltic Sea. For 39 Caspian terns from colonies along a latitudinal gradient from 57 to 65°N, we identified key migratory routes, stopovers and wintering areas. In autumn these seabirds migrated using coastal and freshwater stopovers along six routes to reach their wintering areas across the Sahel, the Nile River Basin and the southern Iberian Peninsula. In spring, adults returned to the breeding grounds in the Baltic using a time optimizing strategy by reducing time at stopover by 78%, whereas most subadults remained sedentary and some performed only partial return migrations. Of the stopover sites used in both seasons, 58% are protected and have a reported management plan. Conservation strategies in wintering areas, stopover sites that are not protected or had not been previously recognized, and the inclusion of the species in important migratory flyways across Europe and Africa will be important to prevent further population declines of a species that depends on aquatic habitats. [ABSTRACT FROM AUTHOR]

Age and environment are important determinants of reproductive parameters in long‐lived organisms. These factors may interact to determine breeding responses to environmental change, yet few studies have examined the environmental dependence of aging patterns across the entire life span. We do so, using a 20‐yr longitudinal data set of reproductive phenotypes in long‐lived female Nazca boobies (Sula granti), a monogamous seabird breeding in the eastern tropical Pacific. Young and old females may suffer from inexperience and senescence, respectively, and/or practice reproductive restraint. Breeding performance (for breeding participation, breeding date, clutch size, egg volume, and offspring production) was expected to be lower in these age classes, particularly under environmental challenge, in comparison with middle‐aged breeders. Sea surface temperature anomalies (SSTA) represented interannual variation in the El Niño–Southern Oscillation (ENSO) and were one proxy for environmental quality (a population count of clutch initiations was a second). Although only females lay eggs, both sexes care for eggs and nestlings, and the male partner's age, alone or in interaction with female age, was evaluated as a predictor of breeding performance. Middle‐aged females performed better than young and old birds for all reproductive traits. Pairing with a young male delayed breeding (particularly for old females) and reduced clutch size, and pairing with an old male reduced offspring production. Challenging environments increased age effects on breeding probability and breeding date across young to middle ages and for offspring production across middle to old ages. However, important exceptions to the predicted patterns for clutch size and fledging success across young to middle ages suggested that trade‐offs between fitness components may complicate patterns of trait expression across the life span. Relationships between breeding participation, environment, and individual quality and/or experience in young females may also contribute to unexpected patterns for clutch size and fledging success, traits expressed only in breeders. Finally, independent of age, breeding responses of female Nazca boobies to the ENSO did not follow expectations derived from oceanic forcing of primary productivity. During El Niño‐like conditions, egg‐laying traits (clutch size, breeding date) improved, but offspring production declined, whereas La Niña‐like conditions were "poor" environments throughout the breeding cycle. [ABSTRACT FROM AUTHOR]

Background: Studies on animal behaviour often involve the quantification of the occurrence and duration of various activities. When direct observations are challenging (e.g., at night, in a burrow, at sea), animal-borne devices can be used to remotely record the movement and behaviour of an animal (e.g., changing body posture and movement, geographical position) and/or its immediate surrounding environment (e.g., wet or dry, pressure, temperature, light). Changes in these recorded variables are related to different activities undertaken by the animal. Here we explored the use of animal-borne acoustic recorders to automatically infer activities in seabirds. Results: We deployed acoustic recorders on Cape gannets and analysed sound data from 10 foraging trips. The different activities (flying, floating on water and diving) were associated with clearly distinguishable acoustic features. We developed a method to automatically identify the activities of equipped individuals, exclusively from animal-borne acoustic data. A random subset of four foraging trips was manually labelled and used to train a classification algorithm (k-nearest neighbour model). The algorithm correctly classified activities with a global accuracy of 98.46%. The model was then used to automatically assess the activity budgets on the remaining non-labelled data, as an illustrative example. In addition, we conducted a systematic review of studies that have previously used data from animal-borne devices to automatically classify animal behaviour (n = 61 classifications from 54 articles). The majority of studies (82%) used accelerometers (alone or in combination with other sensors, such as gyroscopes or magnetometers) for classifying activities, and to a lesser extent GPS, acoustic recorders or pressure sensors, all potentially providing a good accuracy of classification (> 90%). Conclusion: This article demonstrates that acoustic data alone can be used to reconstruct activity budgets with very good accuracy. In addition to the animal's activity, acoustic devices record the environment of equipped animals (biophony, geophony, anthropophony) that can be essential to contextualise the behaviour of animals. They hence provide a valuable alternative to the set of tools available to assess animals' behaviours and activities in the wild. [ABSTRACT FROM AUTHOR]

Although invasive non‐native species can adversely affect biodiversity in many ways, predation of native species by non‐native species on islands can be severely damaging. Results of numerous studies document non‐native birds preying on birds on islands, but our understanding of the number and type of species affected has been limited by the lack of a global review of these impacts. I identified the non‐native bird species that have been recorded preying on birds, the locations where this predation occurred, and the bird species affected. Because the impacts of non‐native birds can be particularly severe on small islands, I then identified the islands <500 km2 around the world that are occupied by predatory non‐native birds. By taking into account their life‐history traits and predation history, I also identified the near‐threatened and threatened bird species on these islands that they may prey on. The results indicated that predation by non‐native birds was primarily a concern for threatened bird conservation on small islands; almost all predation impacts (91%) on near‐threatened and threatened birds were recorded on islands, and median island size was 106 km2. I also found non‐native bird predation was a poorly known and widespread potential threat to avian biodiversity; worldwide, 194 islands of <500 km2 were occupied by predatory non‐native birds, but information on their impacts was unavailable for most of these islands. On them, where the impacts of non‐native species can be severe, non‐native birds may be preying on approximately 6% of the world's near‐threatened and threatened bird species. Four non‐native bird species I identified have been successfully eradicated from islands. If they were eradicated from the small islands they occupy, 70% of the near‐threatened and threatened bird species I identified would no longer be affected by nest predation by non‐native birds on small islands. Article impact statement: On small islands, non‐native birds may be preying on approximately 6% of the world's near‐threatened and threatened bird species. [ABSTRACT FROM AUTHOR]

In late summer and autumn, the passage of intense tropical cyclones can profoundly perturb oceanic and coastal ecosystems. Direct negative effects on individuals and marine communities can be dramatic, especially in the coastal zone, 1,2,3,4 but cyclones can also enhance pelagic primary and secondary production. 5,6,7,8,9 However, cyclone impacts on open ocean marine life remain poorly understood. Here, we investigate their effects on the foraging movements of a wide-ranging higher predator, the Desertas petrel (Pterodroma deserta), in the mid-latitude North Atlantic during hurricane season. Contrary to previously studied pelagic seabirds in tropical and mid-latitude regions, 10,11 Desertas petrels did not avoid cyclones by altering course, nor did they seek calmer conditions within the cyclone eye. Approximately one-third of petrels tracked from their breeding colony interacted with approaching cyclones. Upon encountering strong winds, the birds reduced ground speed, likely by spending less time in flight. A quarter of birds followed cyclone wakes for days and over thousands of kilometers, a behavior documented here for the first time. Within these wakes, tailwind support was higher than along alternative routes. Furthermore, at the mesoscale (hours–weeks and hundreds of kilometers), sea surface temperature dropped and surface chlorophyll sharply increased, suggesting direct effects on ocean stratification, primary production, and therefore presumably prey abundance and accessibility for surface-feeding petrels. We therefore hypothesize that cyclone wakes provide both predictably favorable wind conditions and foraging opportunities. As such, cyclones may have positive net effects on the demography of many mid-latitude pelagic seabirds and, likely, other marine top-predators. [Display omitted] • Oceanic seabirds move toward tropical cyclones during foraging trips • Tracked birds followed the wakes of cyclones for days and thousands of kilometers • Along the wakes, surface chlorophyll sharply increased due to enhanced mixing • Cyclones generate foraging opportunities for oceanic seabirds Despite their well-known destructiveness for coastal ecosystems, the biological impacts of tropical cyclones in the open ocean are poorly understood. Ventura et al. show that oceanic seabirds approach cyclones and follow along their wakes, suggesting that tropical cyclones generate foraging opportunities for pelagic marine predators. [ABSTRACT FROM AUTHOR]

The ‘Ua‘u (Hawaiian Petrel Pterodroma sandwichensis) is an endangered petrel endemic to the Hawaiian Islands. In this short paper, we describe two cases of Hawaiian Petrels with leucistic plumage recorded on the island of La¯na‘i. In both cases, the birds were chicks that fledged successfully in different years from the same burrow. There is only one other documented case of leucism recorded for this species in the Hawaiian Islands despite intensive monitoring of petrel burrows on Kaua‘i, La¯na‘i, and Maui over the last few decades, highlighting the rarity of this plumage aberration. [ABSTRACT FROM AUTHOR]

Acquiring basic knowledge such as at-sea distribution is often difficult for cryptic seabird species. Northern storm petrels (Hydrobatidae) are one family of seabirds that includes several cryptic species, including Ainley’s Storm Petrel Hydrobates cheimomnestes, which appears quite similar to southern Leach’s H. leucorhous and Townsend’s H. socorroensis Storm Petrels when at sea. For the first time, we describe the at-sea distribution of breeding Ainley’s Storm Petrels obtained using GPS tracking. We found that these birds visit waters of the eastern North Pacific between central Baja California, Mexico and southern Alta California, USA. These findings expand existing knowledge of the range of this species, which had previously been based on a few at-sea sightings and specimens. [ABSTRACT FROM AUTHOR]

Abstract Background Mobile organisms in marine environments are expected to modify their behavior in response to external stressors. Among environmental drivers of animal movement are long-term climatic indices influencing organism distribution and short-term meteorological events anticipated to alter acute movement behavior. However, few studies exist documenting the response of vagile species to meteorological anomalies in coastal and marine systems. Methods Here we examined the movements of Eastern brown pelicans (Pelecanus occidentalis carolinensis) in the South Atlantic Bight in response to the passage of three separate hurricane events in 2 years. Pelicans (n = 32) were tracked with GPS satellite transmitters from four colonies in coastal South Carolina, USA, for the entirety of at least one storm event. An Expectation Maximization binary Clustering algorithm was used to discretize pelican behavioral states, which were pooled into ‘active’ versus ‘inactive’ states. Multinomial logistic regression was used to assess behavioral state probabilities in relation to changes in barometric pressure and wind velocity. Results Individual pelicans were more likely to remain inactive during tropical cyclone passage compared to baseline conditions generally, although responses varied by hurricane. When inactive, pelicans tended to seek shelter using local geomorphological features along the coastline such as barrier islands and estuarine systems. Conclusions Our telemetry data showed that large subtropical seabirds such as pelicans may mitigate risk associated with spatially-extensive meteorological events by decreasing daily movements. Sheltering may be related to changes in barometric pressure and wind velocity, and represents a strategy common to several other classes of marine vertebrate predators for increasing survival probabilities.

The family Chlamydiaceae is comprised of obligate intracellular bacteria, some of which are significant pathogens of humans and domestic animals. Magellanic penguins (Spheniscus magellanicus) are susceptible to Chlamydia psittaci outbreaks in captivity, and serological surveys detected antibodies against C. psittaci (or antigenically similar organisms) in wild populations of this species. To investigate the occurrence of Chlamydiaceae in wild Magellanic penguins, 167 cloacal swabs were collected from apparently healthy individuals at four breeding colonies along the coast of Chubut, Argentina. Real-time PCR revealed the presence of DNA from Chlamydiaceae-like bacteria in 61 cloacal swabs (36.5%). Detection did not correlate to nutritional status or to meaningful hematological abnormalities. Isolation in monkey kidney cells was unsuccessful, but DNA sequences for the 16S–23S rRNA region were obtained from one sample. Phylogenetic analysis showed a close relationship to unidentified Chlamydiaceae-like bacteria found in chinstrap penguins (Pygoscelis antarcticus) in Antarctica and seagulls in France and the Bering Sea, and to Chlamydiifrater spp. isolated from flamingos in France. Further studies are necessary to clarify the taxonomy and investigate the epidemiology, pathogenicity, and zoonotic potential of this group of Chlamydiaceae-like bacteria.

Colonially breeding birds and mammals form some of the largest gatherings of apex predators in the natural world and have provided model systems for studying mechanisms of population regulation in animals. According to one influential hypothesis, intense competition for food among large numbers of spatially constrained foragers should result in a zone of prey depletion surrounding such colonies, ultimately limiting their size. However, while indirect and theoretical support for this phenomenon, known as "Ashmole's halo," has steadily accumulated, direct evidence remains exceptionally scarce. Using a combination of vesselbased surveys and Global Positioning System tracking, we show that pelagic seabirds breeding at the tropical island that first inspired Ashmole's hypothesis do indeed deplete their primary prey species (flying fish; Exocoetidae spp.) over a considerable area, with reduced prey density detectable >150 km from the colony. The observed prey gradient was mirrored by an opposing trend in seabird foraging effort, could not be explained by confounding environmental variability, and can be approximated using a mechanistic consumption-dispersion model, incorporating realistic rates of seabird predation and random prey dispersal. Our results provide a rare view of the resource footprint of a pelagic seabird colony and reveal how aggregations of these central-place foraging, marine top predators profoundly influence the oceans that surround them. [ABSTRACT FROM AUTHOR]

Accurate and repeatable population estimates are key to establishing population trends and conservation status. Rako, or Buller's Shearwater (Ardenna bulleri) is a seabird endemic to New Zealand that breeds only on the Poor Knights Islands, but forages throughout wider areas of the Pacific Ocean during the non-breeding season. The lack of threats on the breeding grounds and the wide foraging range of Buller's Shearwaters makes them ideal sentinels of ocean health. Although they are commonly seen at sea and the population in the 1980s was thought to be around 2.5 million birds, other rapid land-based surveys suggested a much lower figure (~100,000 pairs on Aorangi), and no thorough population estimate has been undertaken to date. We calculated a population estimate for Buller's Shearwater based on burrow counts and state of occupancy conducted at the Poor Knights during either the 2016–2017 or the 2017–2018 breeding seasons. We incorporated information on habitat availability and preference in population models. Our estimate of 78,645 (95% confidence interval 67,176–89,178) active burrows, broadly representing breeding pairs, is lower than some previously published assessments. This is a repeatable quantitative study of the Buller's Shearwater breeding population, including breeding activity, and provides critical baseline data to determine population trends for this potentially important marine indicator species. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin de la Societe Zoologique de France is the property of Societe Zoologique de France 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.)

Species that are constantly exposed to disturbances, such as human disturbance or non‐lethal contacts with predators or conspecifics, can experience chronic stress. Within a species range, variation in the frequency and predictability of such disturbances can lead to population differences in stress responses. Here, we investigated the stress response of Little Penguins Eudyptula minor to an introduced predator and a conspecific at two South Australian colonies that differed in habitat, conspecific density, levels of human disturbance and predation risk (high, low). We used playback experiments of Cat Felis catus or Little Penguin calls and recorded the behaviour and physiological (heart rate) response of adults in relation to playback type (Cat, Penguin) as well as habitat characteristics (habitat type, nest type, nest visibility) and number of conspecifics present. Our results showed that individuals from the high‐disturbance colony (also living in a mixed habitat with fewer neighbours) exhibited higher vigilance and heart rate responses than individuals from the low‐disturbance colony (living in a closed habitat with a high number of neighbours). Our results highlight that guidelines for managing penguin species cannot be generalized across populations and need to be colony‐specific. [ABSTRACT FROM AUTHOR]

An Atlantic yellow-nosed albatross (Thalassarche chlororhynchos) was found on shore 3 days after having been captured at sea by researchers. It presented very lethargic, moderately dehydrated, and in poor body condition. It was mildly hypothermic, with moderate pediculosis, and dark malodorous feces with yellow urates. The bird had a 48-g satellite transmitter attached with a backpack-style chest harness, which caused an ulcerative lesion on the interscapular area. The bird was severely anemic (packed cell volume, 18%), and plasma chemistry results were suggestive of a severe rhabdomyolysis (aspartate transaminase, 3620 U/L; creatine kinase, 100 400 U/L). We hypothesized that capture myopathy occurred because of a combination of capture stress and prolonged physical restraint by researchers, stress associated with repeated attempts by the bird to remove the satellite-transmitter harness, and a lengthy road transport to the rehabilitation center. A treatment protocol, which relied on a combination of aggressive fluid therapy, selenium, vitamins E and B12, and multivitamin supplementation, was administered after the initial physical assessment of the albatross. Isoflurane inhalation anesthesia was used to minimize stress associated with the performed medical procedures (eg, physical examination, removal of the satellite transmitter harness, blood collection, and wound management). Measures were adopted while the bird was hospitalized to reduce stress (eg, quiet and comfortable environment with visual barriers and restricting handling of the patient to experienced staff). Clinical and hematological monitoring was used to assess the patient's condition as the bird gradually recovered while hospitalized. The albatross was successfully released 28 days after the initial presentation, suggesting that the medical protocol employed in this case may be useful for the treatment of capture myopathy in albatrosses and other birds. [ABSTRACT FROM AUTHOR]

Predicting how populations may respond to climate change and anthropogenic pressures requires detailed knowledge of demographic traits, such as survival and reproduction. However, the availability of these data varies greatly across space and taxa. Therefore, it is common practice to conduct population assessments by filling in missing values from surrogate species or other populations of the same species. Using these independent surrogate values concurrently with observed data neglects the life‐history trade‐offs that connect the different aspects of a population's demography. Consequently, this approach introduces biases that could ultimately lead to erroneous management decisions.We use a Bayesian hierarchical framework to combine fragmented multi‐population data with established life‐history theory and reconstruct population‐specific demographic data across a substantial part of a species breeding range. We apply our analysis to a long‐lived colonial species, the black‐legged kittiwake Rissa tridactyla, that is classified as globally Vulnerable and is highly threatened by increasing anthropogenic pressures, including offshore renewable energy development. We then use a projection analysis to examine how the reconstructed demographic parameters may improve population assessments, compared to models that combine observed data with independent surrogate values.Demographic parameters reconstructed using a hierarchical framework can be utilised in a range of population modelling approaches. They can also be used as reference estimates to assess whether independent surrogate values are likely to over or underestimate missing demographic parameters. We show that surrogate values from independent sources are often used to fill in missing parameters that have large potential demographic impact, and that resulting biases are driven in unpredictable directions thus precluding assessments from being consistently precautionary.Synthesis and applications. Our study dramatically increases the spatial coverage of population‐specific demographic data for black‐legged kittiwakes. The reconstructed demographic parameters presented can also be used immediately to reduce uncertainty in the consenting process for offshore wind development in the United Kingdom and Ireland. More broadly, we show that the reconstruction approach used here provides a new avenue for improving evidence‐based management and policy action for animal and plant populations with fragmented and error prone demographic data. [ABSTRACT FROM AUTHOR]

This paper presents a seabird biologging system with a compact waterproof airflow sensor. Although biologging methods have attracted attention in the evaluation of seabird flight performance, a direct measurement method of airflow velocity has not yet been established. When an airflow sensor is added to a biologging system, a more accurate assessment of the flight performance can be obtained. We developed a compact Pitot tube-type airflow sensor that is specialized for seabird biologging systems. Here, we integrated micro electro mechanical system (MEMS) sensor chips and a sensing circuit into the Pitot tube housing. Then, we conducted a wind tunnel experiment using a stuffed seabird and the fabricated sensor. The results confirmed that the sensor responds to the wind speed even when attached to the dorsal surface of the seabird. Based on the above, we believe that the proposed sensor can be applied to practical seabird biologging systems. [ABSTRACT FROM AUTHOR]

Copyright of Avian Conservation & Ecology is the property of Resilience Alliance 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.)

The tufted puffin Fratercula cirrhata (Charadriiformes: Alcidae) is distributed throughout the boreal and low Arctic areas of the North Pacific, from California, USA to Hokkaido, Japan. Few studies have investigated the genetic diversity of this species. Therefore, we analyzed the genetic diversity of two captive populations using nucleotide sequences of two mitochondrial loci (COX1 and D-loop) and one nuclear locus (RHBG). We sequenced these loci for birds from Tokyo Sea Life Park (Kasai Rinkai Suizokuen), originally from Alaska, and birds from Aqua World Oarai, originally from far eastern Russia. We found five COX1 haplotypes and 17 D-loop haplotypes for the mitochondrial loci, and obtained 14 predicted haplotypes for the nuclear RHBG locus. The major haplotypes of all three loci occurred in individuals from both populations. Thus, there were no clear genetic differences between the populations with respect to these three loci. Although the breeding range of the tufted puffin covers the boreal and low Arctic from California to Hokkaido, our results suggest that the species has not genetically diverged within its breeding range. [ABSTRACT FROM AUTHOR]

The extrinsic and intrinsic factors affecting differing reproductive strategies among populations are central to understanding population and evolutionary ecology. To evaluate whether individual reproductive strategies responded to annual patterns in marine productivity and age‐related processes in a seabird we used a long term (2003–2013), a continuous dataset on nest occupancy and attendance at the colony by little penguins (Eudyptula minor) at Phillip Island (Victoria, Australia). We found that concurrent with a secondary annual peak of marine productivity, a secondary peak in colony attendance and nest occupancy was observed in Autumn (out of the regular breeding season in spring/summer) with individuals showing mating‐like behavior. Individuals attending this autumn peak averaged 2.5 years older than those individuals that exclusively bred during spring/summer. Rather than being a naïve response by younger and inexperienced birds misreading environmental cues, our data indicate that the autumn peak attendance is an earlier attempt to breed by older and more experienced penguins. Therefore, we provide strong support for the fundamental prediction of the life‐history theory of increasing investment in reproduction with age to maximize lifetime fitness as future survival prospects diminish and experience increases. [ABSTRACT FROM AUTHOR]

Background: According to central place foraging theory, animals will only increase the distance of their foraging trips if more distant prey patches offer better foraging opportunities. Thus, theory predicts that breeding seabirds in large colonies could create a zone of food depletion around the colony, known as "Ashmole's halo". However, seabirds' decisions to forage at a particular distance are likely also complicated by their breeding stage. After chicks hatch, parents must return frequently to feed their offspring, so may be less likely to visit distant foraging patches, even if their quality is higher. However, the interaction between prey availability, intra-specific competition, and breeding stage on the foraging decisions of seabirds is not well understood. The aim of this study was to address this question in chinstrap penguins Pygoscelis antarcticus breeding at a large colony. In particular, we aimed to investigate how breeding stage affects foraging strategy; whether birds foraging far from the colony visit higher quality patches than available locally; and whether there is evidence for intraspecific competition, indicated by prey depletions near the colony increasing over time, and longer foraging trips. Methods: We used GPS and temperature-depth recorders to track the foraging movements of 221 chinstrap penguins from 4 sites at the South Orkney Islands during incubation and brood. We identified foraging dives and calculated the index of patch quality based on time allocation during the dive to assess the quality of the foraging patch. Results: We found that chinstrap penguin foraging distance varied between stages, and that trips became shorter as incubation progressed. Although patch quality was lower near the colony than at more distant foraging patches, patch quality near the colony improved over the breeding season. Conclusions: These results suggest chinstrap penguin foraging strategies are influenced by both breeding stage and prey distribution, and the low patch quality near the colony may be due to a combination of depletion by intraspecific competition but compensated by natural variation in prey. Reduced trip durations towards the end of the incubation period may be due to an increase in food availability, as seabirds time their reproduction so that the period of maximum energy demand in late chick-rearing coincides with maximum resource availability in the environment. This may also explain why patch quality around the colony improved over the breeding season. Overall, our study sheds light on drivers of foraging decisions in colonial seabirds, an important question in foraging ecology. [ABSTRACT FROM AUTHOR]

Seabirds are among the most endangered avian groups, with populations declining worldwide because of various threats, including invasive nest predators. Similar decreasing trends are occurring in the Southern Grenadines; however, the causes of decline remain uncertain, although non‐native rats have been suspected. Therefore, our objective was to determine whether non‐native rats are present on five Southern Grenadine islands that harbor seabird colonies, during May–July 2014–2017, using four methods (chew cards, tunnels, cameras, and questionnaires). Les Tantes East and Lee Rocks were the only two islands where cameras detected black rats (Rattus rattus). Although rat occupancy was low (0.125 ± 0.061) and the number of individuals and nesting attempts increased (except in 2017) for most species, the low detection probability and small number of nests prevented any inference about rat impact on seabirds. Rats might have affected seabird colonies, but other factors, such as seabird harvest, prey availability, or climatic fluctuations, could have also driven previous seabird population declines in the Southern Grenadines. However, non‐native rats are present and future research should focus on estimating their density and distribution on these and other islands of the region before an appropriate rat eradication program can be implemented. [ABSTRACT FROM AUTHOR]