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In recent years, there have been increasing reports of ingestion of marine plastic debris in seabirds. Our aim was to assess the frequency and effects of ingested plastic debris in pre-fledging Short-tailed Shearwaters (Puffinus tenuirostris) in Tasmania. We conducted necropsies of 171 Shearwater chicks, confiscated after illegal poaching, to determine the presence of plastic debris in the proventriculus and ventriculus. We also examined whether there was a correlation between body condition (based on body mass and fat-scores) and quantity of plastic ingested (by count and weight). We recorded 1032 ingested plastic particles, consisting of industrial plastic (31%) and user plastic (69%). Most of the Shearwater chicks (96%) contained plastic debris with a mean of 148.1 mg per bird (s.e. 8.1). Most plastic was found in the ventriculus. Light-coloured plastic dominated (63.8%), with the rest medium (22.1%) and dark (14.1%) plastics. We found that total mass of ingested plastic was not significantly related to body condition, or fat-scores or mass individually. Our study highlights the prevalence of plastic pollution in apparently healthy Shearwater chicks and underscores concern regarding the effects of increasing marine pollution on a global scale.

Following breeding, sooty shearwaters Puffinus griseus leave New Zealand waters and migrate to 1 of 3 distinct areas in the North Pacific Ocean, effectively exploiting environmen- tal resources across a large proportion of this northern ocean basin. In this study, we combined electronic tracking technology with stable isotope analyses (δ 15 N and δ 13 C) of feathers grown dur- ing the non-breeding period in order to evaluate whether isotope signatures can be used to iden- tify specific non-breeding areas used by sooty shearwaters. A region to the east of Japan was utilised by the majority of tracked birds, whereas others used areas off the west coast of North America. Stable isotope values of feathers allowed the discrimination of individuals that used each of the 3 different non-breeding areas, and suggested that birds off Japan can be further separated into 'coastal' and 'offshore' groups. Our results confirm the utility of using stable isotope analysis, validated by tracking devices, as a tool to determine distribution and habitat use of a long-range oceanic migrant, the sooty shearwater. These results also highlight the resource connectivity between the northern and southern Pacific Ocean basin.

In long-lived species, care-giving parents are expected to balance their own condition with that of their offspring. Many species of seabirds display a unique behavioural adaptation for managing these conflicting demands known as dual foraging, in which long trips, largely for self-maintenance, are alternated with short trips, which are primarily for offspring care. While dual foraging is a widely studied behaviour, it entails a complication that is seldom discussed: if parents independently employ a dual-foraging strategy, chicks might be abandoned for extended periods when the long trips of both partners coincide. Whether partners coordinate their dual-foraging strategies, however, is largely unknown. To investigate this possibility, we used radiofrequency identification readers coupled with passive integrated transponder tags to record extended sequences of foraging trips for breeding Manx shearwaters, Puffinus puffinus. Our results show a pattern of foraging trips that indicates a high level of coordination between parents, which facilitates consistent provisioning. Additionally, we show that the propensity for pairs to coordinate declines across the chick-rearing period. Given the potential costs of not coordinating, we expect this behaviour to be widely spread among dual-foraging species.

Indices calculated from “muttonbirding” diaries collected by the Rakiura Māori of New Zealand were correlated with future values of the Southern Oscillation Index (SOI), and the Pacific Decadal Oscillation (PDO) from 1957 to 2010. Spearman correlations showed that La Nina events tended to occur after those harvest seasons with relatively high success and chick size, whereas El Nino events tended to occur after harvest seasons with relatively low success and chick size. Generalized boosted regression models show that chick size alone is able to predict shifts in SOI from 0 to 12 months after the harvest. A model that included chick size, 2-year average PDO (prior to the harvest), and one year averages of SOI (prior to the harvest), was able to predict shifts in SOI 13–20 months after the harvest. It is likely that sooty shearwater adults (and therefore chick size and quantity) are being affected by oceanographic conditions that are also precursors to shifts in SOI, and that there is a complex interaction between PDO prior to the harvest, the harvest indices and SOI. The location and timing of adult birds at the time they are provisioning chicks could lead to potential mechanisms and requires further study.

Seabirds are marine top predators and accumulate high levels of metals and metalloids in their tissues. Contamination by metals in the highly productive offshore region has become a matter of public concern. It is home to 80% of the seabird population in the U.S.A., 95% of northern fur seals (Callorhinus ursinus), and major populations of Steller sea lions (Eumetopias jubatus), walruses (Odobenus rosmarus) and whales. Here, the concentrations of eight heavy metals (Hg, Cd, Cr, Co, Ni, Cu, Zn and Pb) and a metalloid (As) in the liver and kidneys of the northern fulmar (Fulmarus glacialis), thick-billed murre (Uria lomvia), short-tailed shearwater (Puffinus tenuirostris), tufted puffin (Fratercula cirrhata) and horned puffin (Fratercula corniculata) collected in the Bering Sea were measured. As proxies of trophic level and habitat, nitrogen (delta N-15) and carbon (delta C-13) stable isotope ratios of breast muscles were also measured. Hepatic Hg concentration was high in northern fulmar, whereas Cd level was high in tufted puffin and northern fulmar. The Hg concentration and d15N value were positively correlated across individual birds, suggesting that Hg uptake was linked to the trophic status of consumed prey. Furthermore, Hg concentration in our study was higher than those of the same species of seabirds collected in 1990.

Compass orientation is central to the control of animal movement from the scale of local food-caching movements around a familiar area in parids and corvids to the first autumn vector navigation of songbirds embarking on long-distance migration. In the study of diurnal birds, where the homing pigeon, Columba livia, has been the main model, a time-compensated sun compass is central to the two-step map-and-compass process of navigation from unfamiliar places, as well as guiding movement via a representation of familiar area landmarks. However, its use by an actively navigating wild bird is yet to be shown. By phase shifting an animal's endogenous clock, known as clock-shifting, sun-compass use can be demonstrated when the animal incorrectly consults the sun's azimuthal position while homing after experimental displacement. By applying clock-shift techniques at the nest of a wild bird during natural incubation, we show here that an oceanic navigator—the Manx shearwater, Puffinus puffinus—incorporates information from a time-compensated sun compass during homeward guidance to the breeding colony after displacement. Consistently with homing pigeons navigating within their familiar area, we find that the effect of clock shift, while statistically robust, is partial in nature, possibly indicating the incorporation of guidance from landmarks into movement decisions. Padget et al. show that a wild bird makes use of a time-compensated sun compass during active navigation. By measuring the minute-by-minute orientation of GPS-tracked Manx shearwaters homing under clock shift from distant release sites, the authors demonstrate that a sun compass is fundamental even once visual landmarks are available.

International audience; Marine protected areas (MPAs) are considered one of the main tools in both fisheries and conservation management to protect threatened species and their habitats around the globe. However, MPAs are underrepresented in marine environments compared to terrestrial environments. Within this context, we studied the Atlantic non-breeding distribution of the southern population of Balearic shearwaters (Puffinus mauretanicus) breeding in Ibiza during the 2011-2012 period based on global location sensing (GLS) devices. Our objectives were (1) to identify overall Important Atlantic Areas (IAAs) from a southern population, (2) to describe spatio-temporal patterns of oceanographic habitat use, and (3) to assess whether existing conservation areas (Natura 2000 sites and marine Important Bird Areas (IBAs)) cover the main IAAs of Balearic shearwaters. Our results highlighted that the Atlantic staging (from June to October in 2011) dynamic of the southern population was driven by individual segregation at both spatial and temporal scales. Individuals ranged in the North-East Atlantic over four main IAAs (Bay of Biscay: BoB, Western Iberian shelf: WIS, Gulf of Cadiz: GoC, West of Morocco: WoM). While most individuals spent more time on the WIS or in the GoC, a small number of birds visited IAAs at the extremes of their Atlantic distribution range (i.e., BoB and WoM). The chronology of the arrivals to the IAAs showed a latitudinal gradient with northern areas reached earlier during the Atlantic staging. The IAAs coincided with the most productive areas (higher chlorophyll a values) in the NE Atlantic between July and October. The spatial overlap between IAAs and conservation areas was higher for Natura 2000 sites than marine IBAs (areas with and without legal protection, respectively). Concerning the use of these areas, a slightly higher proportion of estimated positions fell within marine IBAs compared to designated Natura 2000 sites, with Spanish and Portuguese conservation areas being the most visited. Our results support the current design of conservation areas in Spain and Portugal regarding the protection of adult breeders of this highly mobile species.

SummaryThe Balearic Shearwater Puffinus mauretanicus is considered one of the most threatened seabirds in the world, with the breeding population thought to be in the range of 2,000–3,200 breeding pairs, from which global population has been inferred as 10,000 to 15,000 birds. To test whether the actual population of Balearic Shearwaters is larger than presently thought, we analysed the data from four land-based census campaigns of Balearic Shearwater post-breeding migration through the Strait of Gibraltar (mid-May to mid-July 2007–2010). The raw results of the counts, covering from 37% to 67% of the daylight time throughout the migratory period, all revealed figures in excess of 12,000 birds, and went up to almost 18,000 in two years. Generalised Additive Models were used to estimate the numbers of birds passing during the time periods in which counts were not undertaken (count gaps), and their associated error. The addition of both counted and estimated birds reveals figures of between 23,780 and 26,535 Balearic Shearwaters migrating along the north coast of the Strait of Gibraltar in each of the four years of our study. The effects of several sources of bias suggest a slight potential underestimation in our results. These figures reveal the urgent need to reformulate the population viability analysis for the species, and then if necessary reconsider its conservation status.

Rakiura Māori (New Zealand's southernmost group of indigenous peoples) have harvested the chicks of burrow-nesting Sooty Shearwaters (Tītī; Puffinus griseus) for generations. As part of the harvest process, some families have maintained annual harvest diaries, some dating back to the 1950s. We used generalized boosted regression models, a machine-learning algorithm, to calculate a harvest index that takes into account factors that could impact the numbers of birds taken on any given hunt. For predicted vs. observed values, r2 was between 0.59 and 0.90 for the nanao (first half of the season, when chicks are harvested from burrows during the day) and 0.67 and 0.88 for the rama (second half of the season, during which chicks are harvested from the surface at night). Exploration of the controlling factors of the models revealed that “day of season” plays an important role in predicting daily harvest during the second half of the season (the rama). The nightly tally in the rama peaked approximately halfway through (10–15 days in), which is probably related to the timing of birds emerging from burrows to fledge. The models also suggested that data from the rama (when chicks are 100–120 days old) may be the most suitable for long-term monitoring of populations of Sooty Shearwaters due to consistencies in calculated harvest indices between diaries. Nanao harvest indices, although less consistent, showed patterns similar to those of the rama. When comparing these data to the harvest indices calculated by general linear models by Clucas and colleagues, we found that the agreement between both indices was r2 = 0.31 and r2 = 0.59 for the nanao and rama, respectively. The use of machine learning to correct for extraneous factors (e.g., hunting effort, skill level, or weather) and to create standardized measures could be applied to other systems such as fisheries or terrestrial resource management.

Mass strandings of seabirds occur frequently on many beaches worldwide and commonly involve penguins, petrels, shearwaters, and prions, among others. Large numbers of stranded albatrosses are rarely reported. In this paper, an unusual stranding event that involved five species of Procellariiformes, predominantly the Atlantic Yellow-nosed Albatross (Thalassarche chlororhynchos), is described in southern Brazil. Carcasses and debilitated specimens of Atlantic Yellow-nosed Albatrosses (n = 125), unidentified petrels/shearwaters (Procellariidae; n = 63), White-chinned Petrels (Procellaria aequinoctialis; n = 52), Great Shearwaters (Puffinus gravis; n = 11), Manx Shearwaters (Puffinus puffinus; n = 4) and Cory's Shearwater (Calonectris borealis; n = 1) were found stranded between 15 and 22 March 2013. Atlantic Yellow-nosed Albatrosses (n = 20) and White-chinned Petrel (n = 1) were found alive and remained in the rehabilitation center for a few days before being released. A total of at least 256 birds...

The marine ecosystems of the Bering Sea and adjacent southern Chukchi Sea are experiencing rapid changes due to recent reductions in sea ice. Short-tailed shearwaters Puffinus tenuirostris visit this region in huge numbers between the boreal summer and autumn during non-breeding season, and represent one of the dominant top predators. To understand the implications for this species of ongoing environmental change in the Pacific sub-Arctic and Arctic seas, we tracked the migratory movements of 19 and 24 birds in 2010 and 2011, respectively, using light-level geolocators. In both years, tracked birds occupied the western (Okhotsk Sea and Kuril Islands) and eastern (southeast Bering Sea) North Pacific from May to July. In August–September of 2010, but not 2011, a substantial proportion (68 % of the tracked individuals in 2010 compared to 38 % in 2011) moved through the Bering Strait to feed in the Chukchi Sea. Based on the correlation with oceanographic variables, the probability of shearwater occurrence was highest in waters with sea surface temperatures (SSTs) of 8–10 °C over shallow depths. Furthermore, shearwaters spent more time flying when SST was warmer than 9 °C, suggesting increased search effort for prey. We hypothesized that the northward shift in the distribution of shearwaters may have been related to temperature-driven changes in the abundance of their dominant prey, krill (Euphausiacea), as the timing of krill spawning coincides with the seasonal increase in water temperature. Our results indicate a flexible response of foraging birds to ongoing changes in the sub-Arctic and Arctic ecosystems.

Primary, tail and body moult of three seabirds from Tristan da Cunha archipelago were studied by castnetting offshore south Brazil from February 2006 to August 2007. Timing, duration and synchronization of primary and tail moult are described relative to the annual calendar. Body moult overlapped breeding in Atlantic yellow-nosed albatrosses (Thalassarche chlororhynchos), but tail and primary moult did not. Spectacled petrels (Procellaria conspicillata) had protracted body moult, whereas primary and tail moult were completed by August. We documented onset of primary moult during chick-rearing in spectacled petrels and great shearwaters (Puffinus gravis) of unknown breeding status, and suggest that the south-west Atlantic Ocean holds important numbers of moulting birds of both species during the summer–early autumn. The albatrosses and the spectacled petrels replaced rectrices alternately. Great shearwaters replaced rectrices outward, starting at the central pair. Primary, tail and body moult largely overlap in all three species, suggesting that the metabolic costs of primary moult may not be overly restrictive. Metabolic and nutritional ability to afford simultaneous moult of different feather tracts support the idea that impaired flight caused by wing moult is a strong factor driving no overlap of primary moult and breeding.

Plastic pollution is widespread in the marine environment, and plastic ingestion by seabirds is now widely reported for dozens of species. Beached Northern Fulmars, Great Shearwaters, Sooty Shearwaters and Cory’s Shearwaters are found on Sable Island, Nova Scotia, Canada regularly, and they can be used to assess plastic pollution. All species except Cory’s Shearwaters contained plastic debris in their gastrointestinal tracts. Northern Fulmars, Sooty Shearwaters and Great Shearwaters all showed high prevalence of plastic ingestion (>72%), with Northern Fulmars having the highest number and mass of plastics among the species examined. There was no difference in plastic ingestion between sexes or age classes. In all species user plastics made up the majority of the pieces found, with industrial pellets representing only a small proportion in the samples. Sable Island could be an important monitoring site for plastic pollution in Atlantic Canada.

In this study, we report the (210)Po and (210)Pb concentrations of bone, muscle and liver samples that were obtained from twelve different marine bird species stranded on beaches in the central-north region of Rio de Janeiro State. Both radionuclides were highly concentrated in the liver samples; however, the lowest mean (210)Po/(210)Pb activity ratio (1.3) was observed in bones compared with liver and muscle (16.8 and 13.8, respectively). Among the species that were studied, Fregata magnificens, with a diet based exclusively on fish, had the lowest (210)Pb and (210)Po concentrations and the lowest (210)Po/(210)Pb activity ratio. The (210)Po concentrations in Puffinus spp. liver samples followed a log-normal distribution, with a geometric mean of 300 Bq kg(-1)wet weight. Only two references pertaining to (210)Po in marine birds were found in a Web of Science search of the literature, and each study reported a different concentration value. The values determined in this experiment are consistent with those in one of the previous studies, which also included one of the species studied in this work. No values for (210)Pb in marine birds have been published previously.

ResumenSe documenta la presencia de aberraciones de pigmentos de melaninas en la coloración de las plumas en 4 especies acuáticas en Baja California Sur: Podiceps nigricollis, Egretta rufescens, Puffinus opisthomelas y Larus occidentalis. Estas observaciones representan los primeros registros de leucismo en México para estas especies. La documentación de este tipo de casos puede ayudar a entender la frecuencia de las aberraciones y su variación entre los diferentes grupos de aves.AbstractWe report the occurrence of plumage pigment aberrations in 4 species of waterbirds in Baja California Sur: Egretta rufescens, Larus occidentalis, Podiceps nigricollis, Puffinus opisthomelas. These observations represent the first leucistic records for these species for Mexico. The documentation of such cases can help to understand the impact of chromatic aberrations, and their variation between different groups of birds.

Freshwater discharge from large rivers into the coastal ocean creates tidally-driven frontal systems known to enhance mixing, primary production, and secondary production. Many authors suggest that tidal plume fronts increase energy flow to fish-eating predators by attracting planktivorous fishes to feed on plankton aggregated by the fronts. However, few studies of plume fronts directly examine piscivorous predator response to plume fronts. Our work examined densities of piscivorous seabirds relative to the plume region and plume fronts of the Columbia River, USA. Common murres (Uria aalge) and sooty shearwaters (Puffinus griseus) composed 83% of all birds detected on mesoscale surveys of the Washington and Oregon coasts (June 2003–2006), and 91.3% of all birds detected on fine scale surveys of the plume region less than 40 km from the river mouth (May 2003 and 2006). Mesoscale comparisons showed consistently more predators in the central plume area compared to the surrounding marine area (murres: 10.1–21.5 vs. 3.4–8.2 birds km

Marine birds have been found to ingest plastic debris in many of the world's oceans. Plastic accumulation data from necropsies findings and regurgitation studies are presented on 13 species of marine birds in the North Atlantic, from Georgia, USA to Nunavut, Canada and east to southwest Greenland and the Norwegian Sea. Of the species examined, the two surface plungers (great shearwaters Puffinus gravis; northern fulmars Fulmarus glacialis) had the highest prevalence of ingested plastic (71% and 51%, respectively). Great shearwaters also had the most pieces of plastics in their stomachs, with some individuals containing as many of 36 items. Seven species contained no evidence of plastic debris. Reporting of baseline data as done here is needed to ensure that data are available for marine birds over time and space scales in which we see changes in historical debris patterns in marine environments (i.e. decades) and among oceanographic regions.

We investigated spatio-temporal distribution patterns of the Critically Endangered Balearic shearwater Puffinus mauretanicus in the northern part of its migratory range, using a combination of effort-corrected land- and boat-based survey data (2007−2010). The species was recorded regularly along the western English Channel (Western Channel) coasts of northwest France and the southwest UK, with peak counts occurring during the summer and autumn months. Foraging aggregations comprising hundreds to thousands of birds (~1 to 20% of the global population) were recorded in the large shallow embayments of northern Brittany in all sur- vey years. Elsewhere, most birds were recorded on passage, with maximum birds-per-hour (BPH) of 169 off northwest France and 36 off the southwest UK. Few birds were recorded offshore, beyond sight of land. A distance-from-shore analysis revealed that the species passed closer to shore than other pelagic seabirds such as sooty shearwater Puffinus griseus. A constant-effort sea- sonal survey from the southwest tip of the UK mainland recorded the species on 93% of survey days, with BPH rates peaking in the morning between 08:00 and 11:00 h. These results have important monitoring and conservation implications for this Critically Endangered species. In par- ticular, the records of large aggregations in spatially restricted areas of the Western Channel dur- ing the inter-breeding period suggests the species could be vulnerable to impacts such as oil spills, or disturbance from offshore construction projects. We also provide evidence that some birds remain in the survey area during the breeding season, suggesting it may be an important site for non-breeding birds.

The distribution and thickness of sea ice in the Arctic is changing rapidly, resulting in changes to Arctic marine ecosystems. Seabirds are widely regarded as indicators of marine environmental change, and understanding their distribution patterns can serve as a tool to monitor and elucidate biological changes in the Arctic seas. We examined the at-sea distribution of seabirds in the North American Arctic in July and August, 2007–2012, and marine areas of high density were identified based on bird densities for four foraging guilds. Short-tailed shearwaters (Puffinus tenuirostris) were the most abundant species observed. Northern fulmars (Fulmarus glacialis), thick-billed murres (Uria lomvia), and dovekies (Alle alle) were also sighted in large numbers. Few birds were sighted between Dolphin and Union Strait and King William Island. Areas of high density over multiple years were found throughout the entire western portion of the study area (Bering Sea, Bering Strait, and Chukchi Sea), Lancaster Sound, Baffin Bay, Davis Strait, and the low Arctic waters off Newfoundland. These waters are characterized by high primary productivity. This study is the first to document the marine distribution of seabirds across the entire North American Arctic within the same time period, providing a critical baseline for monitoring the distribution and abundance of Arctic seabirds in a changing Arctic seascape.

A pardela-de-asa-larga (Puffinus lherminieri Lesson 1839) é uma ave marinha tropical que ocorre entre o sul do Canadá e a costa sudeste do Brasil. Puffinus lherminieri é considerado Criticamente Ameaçado na lista vermelha do Brasil principalmente porque ocorre somente em duas localidades, ambas contendo pequenas populações. Porém, muitas ilhas ao longo da costa Brasileira são pouco conhecidas e a descoberta de novas colônias pode ser significativa para a conservação desta espécie. O objetivo deste estudo foi estimar a distribuição geográfica potencial da pardela-de-asa-larga no Brasil, baseada em modelagem de nicho ecológico (MNE) usando o algorítimo Maxent com camadas obtidas do banco de dados ambientais AquaMaps. A MNE foi baseada em 37 registros de áreas de reprodução nas Américas do Norte e Sul. O modelo mostrou uma ampla distribuição potencial, cobrindo a maior parte da costa Atlântica do Brasil e EUA. Quando filtrada para as ilhas ao longo da costa Brasileira o modelo indicou altos níveis de adequação ambiental próximo aos estados de São Paulo, Rio de Janeiro, Espírito Santo e Bahia. Porém, P. lherminieri prefere ilhas em ambientes com água quente e salina. Então, baseado na influência das correntes que atuam na costa Brasileira nós podemos inferir que colônias são mais prováveis de ocorrer em ilhas da costa da Bahia, Espírito Santo e extremo norte do Rio de Janeiro. Estas devem ser intensamente pesquisadas enquanto as ilhas ao sul de Cabo Frio devem ser descartadas. A existência de novas populações pode ter profundos efeitos no estado de conservação desta ave marinha enigmática e raramente vista. Audubon's Shearwater (Puffinus lherminieri Lesson 1839) is a tropical seabird occurring mainly between southern Canada and the southeast coast of Brazil. Puffinus lherminieri is considered Critically Endangered on the Brazilian Red List because it only occurs in two known localities, both of which contain very small populations. However, many offshore islands along the Brazilian coast are poorly known and the discovery of new colonies would be of considerable significance for the conservation of this species. The aim of this study was to estimate the potential geographic distribution of Audubon's Shearwater in Brazil, based on ecological niche model (ENM) using Maxent algorithm with layers obtained from AquaMaps environmental dataset. The ENM was based on 37 records for reproduction areas in North and South America. The model yielded a very broad potential distribution, covering most of the Atlantic coast ranging from Brazil to the US. When filtered for islands along the Brazilian coast, the model indicates higher levels of environmental suitability near the states of São Paulo, Rio de Janeiro, Espírito Santo and Bahia. However, P. lherminieri prefers islands in environments with warm saline water. Thus, based on the influence of currents that act on the Brazilian coast we can infer undiscovered colonies are most likely to occur on islands on coast of Bahia, Espírito Santo and extreme north of the Rio de Janeiro. These should be intensively surveyed while the islands south of Cabo Frio should be discarded. The existence of new populations would have profound effects on the conservation status of this enigmatic and rarely seen seabird.

During the breeding season, seabirds act as central place foragers, constrained to foraging locations nearer to the breeding colony. Variability in energetic demands during phases of the breeding period has the capacity to shape foraging behaviour and influence at-sea foraging behaviour of seabirds due to the changing requirements of the young. Short-tailed shearwaters (Puffinus tenuirostris) (STSH) are a migratory species that migrates between foraging grounds in the northern Pacific Ocean and breeding colonies in south-east Australia. They are known to traverse large sectors of the Southern Ocean to find prey; however the at-sea foraging locations of this species are not spatially and temporally well defined during the breeding season, when energetic requirements are at their peak. We aimed to define key foraging areas of STSH over the pre-laying, incubation and chick-rearing phases of the breeding cycle and identify associations with broad scale oceanographic features. Using light-level geolocation archival tag technology, 27 adults from a southern Tasmanian colony were tracked from their arrival in October to March (2010–2011), providing information on a total of 77 pre-laying exodus, incubation and chick-rearing flights throughout the Southern Ocean. During the pre-laying exodus and incubation phases, the birds visited waters of the sub-Antarctic Front and Polar Frontal Zone. After hatching, the birds made direct flights to the Marginal Ice Zone between 155°E and 90°E. The Antarctic pack ice is a key nursery ground for Antarctic krill (Euphasia superba) over the winter months, and as the ice retreats they become more accessible to STSH when energetic demands, due to chick provisioning, are at their greatest. During late chick-rearing, the birds used waters in the region of the Antarctic Divergence. A foraging index created from activity data collected by the tags indicated that adults spent the greatest amount of time foraging at the furthest extent of each trip. This study has shown that STSH alter their foraging movements over the course of the breeding season, using areas that are likely to provide predictable food resources.

Before visiting or leaving their remote island colonies, seabirds often engage in a behaviour termed ‘rafting’, where birds sit, often in groups, on the water close to the colony. Despite rafting being a widespread behaviour across many seabird taxa, the functional significance of rafting remains unknown. Here we combine global positioning system (GPS) tracks, observational and wind condition data to investigate correlates of rafting behaviour in Manx shearwaters (Puffinus puffinus) at a large colony on Skomer Island, Wales. We test (1) the influence of wind direction on rafting location and (2) whether raft size changes with respect to wind speed. Our approach further allows us to describe day-night trends in (3) raft distance from shore through time; (4) the number of birds present in the nearshore waters through time; and (5) spatial patterns of Manx shearwater rafts in marine waters adjacent to the breeding colony. We find no evidence that wind direction, for our study period, influences Manx shearwater rafting location, yet raft size marginally increases on windier days. We further find rafting birds closer to the shore at night than during the day. Thus, before sunset, birds form a “halo” around Skomer Island, but this halo disappears during the night as more individuals return from foraging trips and raft nearer the colony on Skomer Island. The halo pattern reforms before sunrise as rafts move away from land and birds leave for foraging. Our results suggest that wind conditions may not be as ecologically significant for rafting locations as previously suspected, but rafting behaviour may be especially important for avoiding predators and cleaning feathers.

Attraction of fledgling shearwaters, petrels, and storm-petrels to artificial light hasbeen documented for decades on islands around the world and is considered a significant threatto many species. Although large numbers of downed birds have been observed after being disori-ented by light, several important elements of this ‘fallout’ phenomenon are unknown, includingthe locations along the path from nest to ocean at which attraction and/or disorientation occursand whether fledglings can be attracted back to land after reaching the ocean in numbers largeenough to contribute significantly to fallout. To investigate these questions, we compared ob -served Newell’s shearwater Puffinus newelli fallout records (from 1998 to 2009) on Kauai, USA,with expected numbers generated from several hypothetical models containing basic assumptionsrelated to fledgling movement and attraction to light. Based on our results, the spatial pattern ofobserved fallout is consistent with the amount of light that fledglings may view along their firstflights to and beyond the coastline. This suggests that even fledglings from dark regions of theisland may not be safe because they may view light after reaching the ocean and still be suscepti-ble to attraction. These findings support recent modeling efforts predicting that most birds fledgingfrom Kauai are likely exposed to at least some anthropogenic light. As nocturnal use of light byhumans is unlikely to be eliminated, research on the types of artificial light that are both useful tohumans and safe for seabirds may be crucial for the conservation of these important marine animals.KEY WORDS: Anthropogenic light · GIS-based modeling · Hawaii · Kauai · Light attraction ·Procellariiformes · Newell’s shearwater · Seabird conservation

We documented the population size of Sooty Shearwater on the Wollaston and Hermite Island Groups. A population of at least 100,000 pairs were found on Wollaston and there may be as many as 300,000 pairs in the Wollaston and Hermite Island Groups. We also confirmed the presence of Magellanic Diving-petrel and Fuegian Storm-petrel in the Island Group and discussed the status of these taxa in southern Chile. The status of the mammals found on these islands is also summarised and concerns are raised over the possibility that introduced mammals, especially beavers, muskrats, minks and feral cats may reach these pristine islands affecting seabird populations.

Plastic debris is often ingested by marine predators and can cause health disorders and even death. We present the first assessment of plastic ingestion in Mediterranean seabirds. We quantified and measured plastics accumulated in the stomach of 171 birds from 9 species accidentally caught by longliners in the western Mediterranean from 2003 to 2010. Cory’s shearwaters ( Calonectris diomedea ) showed the highest occurrence (94%) and large numbers of small plastic particles per affected bird (on average N = 15.3 ± 24.4 plastics and mass = 23.4 ± 49.6 mg), followed by Yelkouan shearwaters ( Puffinus yelkouan , 70%, N = 7.0 ± 7.9, 42.1 ± 100.0 mg), Balearic shearwaters ( Puffinus mauretanicus , 70%, N = 3.6 ± 2.9, 5.5 ± 9.7 mg) and the rest of species (below 33%, N = 2.7, 113.6 ± 128.4 mg). Plastic characteristics did not differ between sexes and were not related to the physical condition of the birds. Our results point out the three endemic and threatened shearwater species as being particularly exposed to plastic accumulation.

To understand how animals cope with environmental variability it is necessary to identify the degree of flexibility in a species' diet and foraging mode and the consequences of this flexibility for reproduction. We examined rates of feeding and energy delivery to chicks by a long-lived pelagic seabird, the Short-tailed Shearwater (Puffinus tenuirostris). Individual adults alternated between foraging trips of short and long duration in a dual foraging strategy, but the allocation of time on those trips varied significantly from year to year. In two years when sea-surface temperatures of feeding grounds exploited during short trips were cooler (2005, 2006) adults initially fed their chick more often, then feeding decreased through the chick-rearing period. In the following year of warmer sea-surface temperature (2007), the number of feedings per day was initially low but increased through chick rearing. Despite varied feeding patterns, breeding success was consistently high, yet in 2006 the chicks...

The nomenclatural history of the small Antillean species that now goes by the name Audubon's Shearwater Puffinus lherminieri is briefly summarized. The type material of Puffinus lherminieri Lesson, 1839, supposed to be in a museum in Rochefort, France, could not be located and is presumed lost. The stated type locality “ad ripas Antillarum” is so general as to encompass almost the entire breeding range of the species, which is widely distributed in the Antillean region and has been regarded as showing variation meriting subspecific designation. Although the type locality was apparently legitimately restricted to Guadeloupe in 1948 or earlier, it was elsewhere erroneously restricted to “Straits of Florida” from 1931 to 1998 and up to the present. To resolve these numerous conflicts and uncertainties, a neotype collected in Saint Barthelemy, once administratively part of Guadeloupe, is here designated.

Using mark-recapture, we estimated the age at first return and survival of juveniles of the Sooty Shearwater (Puffinus griseus), a medium-sized burrow-breeding procellariiform, at two New Zealand breeding colonies, Taiaroa Head and The Snares. Sooty Shearwaters were first observed at the colony between 2 and 10 years after being banded as chicks, with a mean of 5.7 years at Taiaroa Head and 5.4 years at The Snares. After accounting for imperfect detectability with a mark-recapture model, we estimate the mean age at first return as 4.8 years. Extrapolation from observed delays between arrival and breeding of the Short-tailed Shearwater (P. tenuirostris) suggests that the mean age at first breeding was 7.7 years. Annualized estimates of survival from 0 to 2 years were 0.54 at Taiaroa Head and 0.41 at The Snares. Overall estimates of the generation time and maximum rate of population growth were 13.1 years and 7.7%, respectively. Many published estimates of age at first return and age at first bree...

We collected fresh Streaked Shearwater Calonectris leucomelas carcasses and describe sex differences in external measurements following sex identification using reproductive organs. Males had significantly deeper bills, longer bills, longer heads, longer tarsi, greater wingspans and greater wing areas than females, but overall wing and tail lengths and aspect ratios did not differ between sexes. Streaked Shearwaters showed a greater degree of sexual dimorphism in bill size than other Puffinus species. Comparing the wing loadings of male and female Streaked Shearwaters, the mass increase required for females to have the same wing loading as males is 0.036 kg. Females could feed to increase their body mass during a foraging trip to have similar wing loading to males.

Oceanic fronts are important foraging areas for many top predators, but they also define biogeographical boundaries to animals in the Southern Ocean and play a role in structuring seabird assemblages. Understanding the factors driving patterns in the spatial and temporal distribution of seabirds is important to infer the likely impact of a changing climate. Latitudinal transects south of Africa in two summers indicate that fronts and sea ice extent play key roles in determining seabird assemblages. We observed 37 seabird taxa and found five seabird assemblages. The Subtropical Convergence and pack ice-edge form the strongest biogeographical boundaries, whereas the Sub-Antarctic Front and Antarctic Polar Front are less well defined. As summer progresses, the Southern Antarctic Circumpolar Current Front (the Antarctic Divergence or southern boundary of the Antarctic Circumpolar Current) becomes important, when a distinct seabird assemblage forms north of the retreating sea ice following an influx of great shearwatersPuffinus gravis(O'Reilly), blue petrelsHalobaena caerulea(Gmelin), Kerguelen petrelsLugensa brevirostris(Lesson) and southern fulmarsFulmarus glacialoides(Smith). Seabird assemblages show strong seasonality and are predictable between years. They are structured primarily by latitudinal gradients and secondarily by seasonal variation in sea-surface temperature and ice cover within their latitudinal habitat zones.

Introduced house miceMus musculusL. have been discovered to be major predators of chicks of the Tristan albatrossDiomedea dabbenenaL. and Atlantic petrelPterodroma incertaSchlegel and to also predate great shearwaterPuffinus gravisO'Reilly chicks at Gough Island, and similar predatory behaviour has been reported for house mice on Marion Island. Observations on Gough Island over three breeding seasons of nesting Atlantic yellow-nosed albatrossesThalassarche chlororhynchosGmelin and dark-mantled sooty albatrossPhoebetria fuscaHilsenberg indicate that house mice are also preying on these two species: the first records of mice preying upon summer-breeding albatross species on Gough Island. Predation on these two albatross species appears to be relatively rare (∼2% for the Atlantic yellow-nosed albatrosses) and ongoing monitoring is required to ascertain if the impact of mice is increasing. Conservation actions to eradicate mice from Gough Island will be of benefit to these species and other species that are being impacted by this invasive species.

The Great Shearwater (Puffinus gravis) is an abundant pelagic seabird that undertakes transequatorial migrations between the North and South Atlantic Ocean. This species is a useful indicator of large-scale alterations in marine dynamics due to its wide geographic range, long-distance migrations, and relative abundance. From 1993 to 2011, 12 separate mortality events, with 4,961 Great Shearwaters recovered, were documented along the eastern coast of the United States. Of these, seven events (n=4,885) occurred in the Southeast (SE) and five (n=76) in the Northeast (NE) United States. The cause of death was determined either by necropsy (n=60) or external examination (n=4,901). All Great Shearwaters stranded along the SE United States were emaciated while 58% were emaciated in the NE United States. No plastic was observed in Great Shearwaters in the SE US (n=27), but the gastrointestinal tract of 82% (n=27) of all stranded birds along the NE United States had at least one plastic bead. There was no evidence of infectious disease or heavy metals in stranded Great Shearwaters examined (n=14, from the 2005 SE event). Stable isotope analysis of feathers (n=9, from a 2007 SE event) suggests dietary differences between emaciated stranded birds and live-caught healthy birds. The temporal distribution of stranding detections suggests a general increase in the number of observed Great Shearwater strandings over the past two decades. From 1993 to 2000 there were a total of three mortality events with 296 individual Great Shearwaters. However, there was a threefold increase in the number of mortality events from 2001 to 2011 (nine events involving 4,665 individuals). The causes of this apparent increase in strandings are unknown but may be due to an increase in reporting effort over the past two decades combined with changing oceanographic conditions in the South Atlantic Ocean, leading to large-scale mortality of emaciated Great Shearwaters along the east coast of the United States.

SummaryThe predatory behaviour of introduced house mice Mus musculus at Gough Island is known to impact on albatross and petrels, resulting in the Tristan Albatross Diomedea dabbenena and Atlantic Petrel Pterodroma incerta being listed as “Critically Endangered” and “Endangered”, respectively. Although predation has been documented for two burrowing petrels and one albatross species, the impact of house mice on other burrowing petrels on Gough Island is unknown. We report burrow occupancy and breeding success of Atlantic Petrels, Soft-plumaged Petrels Pterodroma mollis, Broad-billed Prions Pachyptila vittata, Grey Petrels Procellaria cinerea and Great Shearwaters Puffinus gravis. With the exception of the Great Shearwater, breeding parameters of burrowing petrels at Gough Island were very poor, with low burrow occupancy (range 4–42%) and low breeding success (0–44%) for four species, and high rates of chick mortality in Atlantic Petrel burrows. Breeding success decreased with mass, suggesting that smaller species are hardest hit, and winter-breeding species had lower breeding success than summer breeders. The results indicate that introduced house mice are having a detrimental impact on a wider range of species than previously recorded and are likely to be causing population declines among most burrowing petrels on Gough Island. The very low values of burrow occupancy recorded for Soft-plumaged Petrels and Broad-billed Prions and greatly reduced abundance of burrowing petrels in comparison to earlier decades indicate that Gough Island’s formerly abundant petrel populations are greatly threatened by the impact of predatory house mice which can only be halted by the eradication of this species from the island.

Oxygen and carbon isotope compositions of fossil bird eggshell calcite (δ(18)Ocalc and δ(13)Ccalc) are regularly used to reconstruct paleoenvironmental conditions. However, the interpretation of δ(18)Ocalc values of fossil eggshells has been limited to qualitative variations in local climatic conditions as oxygen isotope fractionations between calcite, body fluids, and drinking water have not been determined yet. For this purpose, eggshell, albumen water, and drinking water of extant birds have been analyzed for their oxygen and carbon isotope compositions. Relative enrichments in (18)O relative to (16)O between body fluids and drinking water of +1.6 ± 0.9 ‰ for semi-aquatic birds and of +4.4 ± 1.9 ‰ for terrestrial birds are observed. Surprisingly, no significant dependence to body temperature on the oxygen isotope fractionation between eggshell calcite and body fluids is observed, suggesting that bird eggshells precipitate out of equilibrium. Two empirical equations relating the δ(18)Ocalc value of eggshell calcite to the δ(18)Ow value of ingested water have been established for terrestrial and semi-aquatic birds. These equations have been applied to fossil eggshells from Lanzarote in order to infer the ecologies of the Pleistocene marine bird Puffinus sp. and of the enigmatic giant birds from the Pliocene. Both δ(13)Ccalc and δ(18)Ocalc values of Puffinus eggshells point to a semi-aquatic marine bird ingesting mostly seawater, whereas low δ(13)Ccalc and high δ(18)Ocalc values of eggshells from the Pliocene giant bird suggest a terrestrial lifestyle. This set of equations can help to quantitatively estimate the origin of waters ingested by extinct birds as well as to infer either local environmental or climatic conditions.

World-wide, many seabirds are affected by fisheries in opposing ways: as a source of mortality from bycatch, but also by providing discards as a predictable and abundant food resource. This applies to the Balearic shearwater Puffinus mauretanicus, the most endangered European seabird, whose time to extinction was estimated at only ˜40 years a decade ago. Since the previous assessment, new data and more sophisticated demographic modelling have become available, and new fishing policies from the European Union (Common Fisheries Policy, CFP) will apply, posing different scenarios for the viability of the species. Thus, there is both an urgent need and an opportunity for a more reliable update of the conservation status of the species. Demographic data were collected between 1985 and 2014 at one of the world's largest colonies. Most demographic parameters were estimated using multievent capture–recapture modelling. Some parameters, such as bycatch rate, immature individual survival and recruitment, were estimated for the first time. We incorporated estimates into stochastic population models to forecast time to extinction and assess the viability under different management scenarios, accounting for upcoming fishing policies. Adult survival was much lower than expected (0·809, SE: 0·013) and largely influenced by bycatch, which accounted for a minimum of 0·455 (SE: 0·230) of total mortality. Breeding success was positively correlated with discard availability. Recruitment started at low rates in 3-year-old birds (0·030, SE: 0·0455), increasing in following age classes and was almost complete at 6 years. Under the present scenario, we predict a time to extinction of 61 years (95% CI: 55–69). Synthesis and applications. Population projections suggest that the actual impact of fisheries on Balearic shearwaters is unsustainable and the imminent discard ban under the new Common Fisheries Policy may accelerate the declining trend. This study demonstrates that reducing the bycatch rates of fisheries is an unavoidable and urgent conservation measure for avoiding the extinction of the species. We also advise setting up demographic long-term studies, to allow researchers to diagnose, with reliability, the effectiveness of management actions. These actions will also benefit many other marine top-predator species affected by this anthropogenic impact., Funds were provided by FEDER programme (Balearic Government), the Spanish Ministries of Economy and Competitiveness (ref. CGL2013-42203-R) and Agriculture, Food and Environment, the H2020 framework EU programme (MINOUW project) and Fundación Biodiversidad.

The marine birds comprising the order Procellariiformes are an ancient and diverse assemblage. A large proportion are both nocturnal and burrow-nesting at their breeding colonies, where in sharp contrast to their behaviour at sea, they are highly vociferous. Virtually nothing is known regarding the adaptive features of this process. Various aspects of vocal behaviour have therefore been investigated from 1981 to 1983 for seven species at breeding stations in both the boreal and sub-tropical North Atlantic Ocean. In addition, the problem of how these birds return to their correct burrows at night has been considered. A detailed study was conducted on the Manx Shearwater Puffinus puffinus. Various approaches showed that immatures contribute most to the calling heard. Males establish and defend burrows, but both sexes partake in aerial calling. Calling at ground level serves both sexual and territorial functions, whereas aerial calling is probably mainly concerned with sexual advertisement. Some males are more silent in flight than others. These probably represent birds as yet without burrows, perhaps the youngest age classes. Flighting activity probably expedites the acquisition of burrows and mates in these birds which are awkward on land, and aerial calling probably improves signalling efficiency in attracting mates. Six other species (Bulweria bulwerii, Calonectris diomedea, Puffinus assimilis, Hydrobates pelagicus, Oceanodroma castro, Pelagodroma marina) were studied. As with Puffinus puffinus, sexual differences in voice exist for all except Bulweria and Pelagodroma, which also lack aerial calls. Thus a functional link exists between flight calls and their sexual divergence. Selection probably favours such divergence in species where males leave burrows to display in flight; the sexual identity of those species whose males do not is unambiguous as they remain in burrows and call. The calls of Puffinus puffinus and Hydrobates pelagicus were compared at local and regional levels. Divergence exists between but not within islands. Vocal drift in Puffinus puffinus is also apparent after several years. The calls of the nocturnal Procellariiformes are reviewed and discussed in relation to their systematics. The potential use of calls in petrel systematics is also evaluated and shown to be useful. Observations on Puffinus puffinus showed that olfactory and auditory cues are not used for burrow homing. Experiments also confirmed this, and point to sufficient visual development in this species, although other senses may be emphasised in different ecological situations.

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

There is a growing need to identify Marine Protected Areas (MPAs) for marine species. For seabirds, MPAs include those near breeding colonies, offshore foraging areas, inshore habitats for wintering species, and migratory bottlenecks. However, frequently there is a lack of readily available current and comprehensive data on foraging areas used by species from particular colonies. Therefore, representative breeding season foraging ranges for each species may be useful alongside other datasets for scoping candidate MPAs. We reviewed studies that estimated foraging range for 25 species of UK breeding seabirds. For representative foraging ranges, we prioritised studies, giving highest value to those based on direct tracking of birds (21%); then those involving indirect estimates using flight speeds and time activity (12%) followed by, boat, aerial, and land-based ‘survey’ observations (46%); and finally we gave lowest value to speculative estimates (21%). Highest confidence was placed in the foraging ranges of northern gannet (Morus bassanus), black-legged kittiwake (Rissa tridactyla), and common guillemot (Uria aalge), and lowest for common gull (Larus canus), common eider (Somateria mollissima), Leach’s (Oceanodroma leucorhoa) and European storm petrels (Hydrobates pelagicus). Both annual and colony-specific variation was evident for some species. Manx shearwater (Puffinus puffinus), northern gannet, and northern fulmar (Fulmarus glacialis), had the largest foraging ranges (maximum ranges >330, 590 and 580 km, respectively), whereas red-throated diver (Gavia stellata) and little tern (Sternula albifrons) had the smallest (maximum ranges 9 and 11 km, respectively). Representative foraging ranges may be useful to suggest likely colony-specific foraging areas, prior to habitat-association modelling for defining candidate MPAs. The approach here has international applicability, and would help progress towards more comprehensive protection of seabird populations.

International audience; Knowledge about the spatial distribution of seabirds at sea is important for conservation. During marine conservation planning, logistical constraints preclude seabird surveys covering the complete area of interest and spatial distribution of seabirds is frequently inferred from predictive statistical models. Increasingly complex models are available to relate the distribution and abundance of pelagic seabirds to environmental variables, but a comparison of their usefulness for delineating protected areas for seabirds is lacking. Here we compare the performance of five modelling techniques (generalised linear models, generalised additive models, Random Forest, boosted regression trees, and maximum entropy) to predict the distribution of Balearic Shearwaters (Puffinus mauretanicus) along the coast of the western Iberian Peninsula. We used ship transect data from 2004 to 2009 and 13 environmental variables to predict occurrence and density, and evaluated predictive performance of all models using spatially segregated test data. Predicted distribution varied among the different models, although predictive performance varied little. An ensemble prediction that combined results from all five techniques was robust and confirmed the existence of marine important bird areas for Balearic Shearwaters in Portugal and Spain. Our predictions suggested additional areas that would be of high priority for conservation and could be proposed as protected areas. Abundance data were extremely difficult to predict, and none of five modelling techniques provided a reliable prediction of spatial patterns. We advocate the use of ensemble modelling that combines the output of several methods to predict the spatial distribution of seabirds, and use these predictions to target separate surveys assessing the abundance of seabirds in areas of regular use.

Non-breeding sooty shearwaters are the most abundant seabird in the California Current Large Marine Ecosystem (CCLME) during boreal spring and summer months. This, combined with relatively great energy demands, reliance on patchy, shoaling prey (krill, squid, and forage fishes), and unconstrained mobility free from central-place-foraging demands—make shearwaters useful indicators of ecosystem variability. During 2008 and 2009, we used satellite telemetry to evaluate shearwater ranging patterns throughout the CCLME and specifically within the US Exclusive Economic Zone (EEZ) among birds captured at three locations: Columbia River Plume, WA; Monterey Bay, CA; and Santa Barbara Channel, CA. Shearwaters ranged throughout the entire CCLME from southeast Alaska to southern Baja California, Mexico. Within the EEZ during 2008 and 2009, shearwaters spent 68% and 46% of time over the shelf ( 1000 m), respectively. In 2008 and 2009, shearwaters spent 22% and 25% of their time in the EEZ within the five west coast National Marine Sanctuaries, respectively; high utilization occurred in non-sanctuary waters of the EEZ. Shearwater utilization distribution (based on the Brownianbridge movement model) among sanctuaries was disproportionate according to sanctuary availability (based on area) within the EEZ. Shearwaters utilized the Monterey Bay sanctuary (2008, 2009) and the Channel Islands sanctuary (2009) disproportionately more than other sanctuaries. Although all five sanctuaries were used by shearwaters, waters outside sanctuary zones appeared significantly more important and likely supported large aggregations of shearwaters. Utilization distributions among individual birds from three discrete capture locations were variable and revealed greater similarity in space-use sharing within capture-location groupings and during 2008 when shearwaters were more aggregated than in 2009. We identified several regional ‘‘habitat hotspot’’ areas, including the Columbia River Plume, Cape

The largest breeding colony of Manx shearwaters (Puffinus puffinus) in the world is found on the Isle of Rum in the inner Hebrides of Scotland. We collected a feather, guano, soil, vegetation, and earthworms near shearwater burrows to determine whether inputs of nitrogen (N) from guano were incorporated into belowground foodwebs. For comparison, similar samples were collected from a nearby plot that was experimentally fertilised 40 years prior. The shearwater feather had the highest level of 15N enrichment (+18‰), followed by guano (+12‰). Soil (+7.5‰) and vegetation (+5.7‰) collected at the burrow entrance were enriched with 15N relative to those collected at 2 m or more away (+0.5 to +3.1‰ for soil, and −2.5 to −4.6‰ for vegetation). In contrast, soil inside the fertilised plot had δ15N ≈ 0, but was enriched with 15N away from the plot edge. Earthworms collected from shearwater greens had enriched 15N signatures relative to earthworms from the fertilised plot (+3.8 and −0.9‰, respectively). Our data suggest that available N is tightly cycled in vegetation and soil for decades, and that shearwater derived N is substantially assimilated by earthworms. Therefore, because earthworms do not occur outside areas of shearwater influence, the birds should be viewed as ecosystem engineers of soil invertebrate foodwebs on Rum.

Bryan's Shearwater (Puffinus bryani) was described in 2011 on the basis of a specimen collected on the Midway Atoll in 1963. This specimen and another recorded on Midway in the early 1990s are the sole reliable records to date. Since 1997, we have found six specimens of a remarkably small Puffinus shearwater morphologically similar to Bryan's Shearwater on the Bonin Islands, northwestern Pacific. In this study, we examined the Bonin samples genetically and confirm that they are of Bryan's Shearwater. A morphological analysis suggests that the small body size and relatively long tail are characteristics of this species. Because the most recent individual was found on an islet to the north of Chichijima Island in 2011, the species has evidently survived in the Bonin Islands, where it may breed, although the exact location remains unclear. Three of the individuals found on an islet off Chichijima Island were carcasses preyed upon by black rats (Rattus rattus). Attempts were made to eradicate rats f...

International audience; In birds, species identity is one of the most important messages conveyed by vocalizations and is the basis for effective acoustic communication between conspecifics. Acoustic analyses can reveal which acoustic cues signal species identity, that is, the cues that could potentially be used by birds for species recognition, whereas playback experiments aim to determine which cues birds actually use for species recognition. Few studies have compared the acoustic cues used for species-specific recognition between closely related species and between sexes within species. We focused on three shearwater species (Puffinus yelkouan, Puffinus mauretanicus, Calonectris d. diomedea) breeding in the Mediterranean basin. In a previous study we showed that males and females of these three closely related species produce broadband calls strongly modulated in frequency and share a wide range of acoustic features signalling species identity. Here, we investigated whether these birds use similar acoustic cues for species recognition. Playback experiments showed that these cues were more similar between species of the genus Puffinus that rely mainly on frequency modulation than between Puffinus and Calonectris species, the latter using mainly frequency spectrum-related cues. In spite of similarities between the Puffinus species, we found substantial differences, P. mauretanicus being more sensitive to frequency value modification than P. yelkouan. We also found that females of the three species rely on more acoustic parameters to identify species than males. Our results show that the species-specific recognition system can show significant differences between closely related species and between sexes. We focus on three shearwater species producing the territorial call. These birds' calls share similar acoustic cues signalling species identity. We conducted playback experiments to reveal vocal cues used for species recognition. These features differed between closely related species and between sexes. Birds with same species signalling systems can have different recognition systems.

A juvenile male greater shearwater (Puffinus gravis) found off the Georgia coast, United States, was lethargic, hypothermic, dehydrated, and emaciated. It was provided with supportive care but subsequently died. The coelomic cavity contained fibrinous fluid intermixed with hundreds of nematodes, some of which protruded through a perforation in the proventriculus. Nematodes were embedded in the wall of the proventriculus from the lamina propria to the serosal surface and were surrounded by granulocytes, epithelioid macrophages, multinucleate giant cells, lymphocytes, and fibroplasia. A full-thickness tear in the proventriculus was lined by heterophils and multinucleate giant cells. The nematode histomorphology was consistent with Anisakis spp. The definitive hosts of Anisakis spp. are marine mammals, which are infected through ingestion of parasitized fish and crustaceans. Marine birds are aberrant hosts of Anisakis spp., and young, inexperienced, immunocompromised birds might be more susceptible to severe infestations. Fatal anisakiasis is rarely reported in birds.

Rakiura Māori seek robust population monitoring to guide sustainable management of the annual take of muttonbird (tītī, Puffinus griseus), in southern New Zealand. Analyses of eight muttonbirder harvest records spanning 67 years and consisting of 6744 hunts show systematic commonalities in seasonal patterns of hunt tallies. General linear models (GLMs) explained between 26% and 75% of variation in the number of chicks caught per hunt within each manu (family harvested area), and strong effects of increased catch rates in the rama harvest phase during wet and windy conditions. The absolute differences in the diary mean hunt tallies show that catches vary considerably among whānau (extended family groups) and cannot be reliably used to compare chick abundance between manu. However, tracking trends in hunt success on the same ground by the same whānau offer a cost-effective means of monitoring population abundance. Recording the duration of hunts and detailed measurements of the number of catchers a...

The impacts of predation by invasive mammals on island fauna are a major driver of insular biodiversity loss. Devastating, hitherto unsuspected impacts of predatory house mice on breeding seabirds have been described recently. We studied the fate of 178 Atlantic Petrel Pterodroma incerta nests at Gough Island, over four seasons, from October 2003 to January 2008. Introduced house mice Mus musculus were found in all study burrows checked for mouse visits. From October 2003 to September 2004, we video-recorded attacks by mice on six (of 13) live, healthy Atlantic Petrel chicks and on one (of three) great shearwater Puffinus gravis chicks. In all years, chicks died from mouse attacks. Stage-specific daily nest survival rates were modelled, from which estimates of breeding success were derived that accounted for the variable exposure periods studied among years. Average daily survival rate of eggs was 0.998, and hatching success through the entire incubation period (55.5 days) was 0.924 [95% confidence interval (CI) 0.903–0.940]. Daily chick survival rates were 0.990, which gave a modelled fledging success of 0.247 (CI 0.165–0.338) over the 138-day chick period, and average annual breeding success (chicks fledged per breeding attempt) of 0.228 (CI 0.150–0.318), which is low compared with congeners. Productivity estimates were used as a parameter in a population simulation model, which predicted a population multiplication rate (λ) of 0.993 (CI = 0.966–1.021). However, in the one season studied from laying to fledging (2007), from 58 nests, only one chick fledged (1.7%). This suggests the wide errors on the model results may obscure a more severe reality. More than 60% of model simulations resulted in an International Union for Conservation of Nature classification of Endangered. Our results add support to calls to eradicate mice from Gough Island. More generally, mice cannot be ignored as a potential threat to island fauna, and island restoration and management plans should routinely include eradication of introduced mice.

Trophic ecology and movements are critical issues for understanding the role of marine predators in food webs and for facing the challenges of their conservation. Seabird forag- ing ecology has been increasingly studied, but small elusive species, such as those forming the 'lit- tle shearwater' complex, remain poorly known. We present the first study on the movements and feeding ecology of the Barolo shearwater Puffinus baroli baroli in a colony from the Azores archi- pelago (NE Atlantic), combining global location-sensing units, stable isotope analyses of feathers (δ 13 C and δ 15 N), stomach flushings and data from maximum depth gauges. During the chick-rear- ing period, parents visited their nests most nights, foraged mainly south of the colony and fed at lower trophic levels than during the non-breeding period. Squid was the most diverse prey (6 fam- ilies and at least 10 different taxa), but species composition varied considerably between years. Two squid families, Onychoteuthidae and Argonautidae, and the fish family Phycidae accounted for 82.3% of ingested prey by number. On average, maximum dive depths per foraging trip reached 14.8 m (range: 7.9 to 23.1 m). After the breeding period, birds dispersed offshore in all directions and up to 2500 km from the breeding colony, and fed at higher trophic levels. Overall, our results indicate that the Barolo shearwater is a non-migratory shearwater feeding at the lowest trophic level among Macaronesian seabirds, showing both diurnal and nocturnal activity and feeding deeper in the water column, principally on small schooling squid and fish. These traits contrast with those of 3 other Azorean Procellariiformes (Cory's shearwater Calonectris diomedea, the Madeiran storm-petrel Oceanodroma castro and Monteiro's storm-petrel O. monteiroi), indi- cating ecological segregation within the Azorean seabird community.

Species of petrels and shearwaters with high diving ability could facilitate the catch of albatrosses in pelagic longline fisheries, because they retrieve bait to the surface from depths that albatrosses cannot reach. Once on the surface, large seabirds such as albatrosses can easily displace smaller species thus gaining access to baited hooks which increases their likelihood of getting caught. This paper evaluates the extent to which diving species (i.e. Procellaria aequinoctialis, Procellaria conspicillata and Puffinus gravis) increase the susceptibility of albatross to bycatch in pelagic longline fisheries. In 48 sets, attacks on baits were quantified. When more than one bird (of the same or different species) tried to attack the same bait this was defined as a multiple attack. There were 384 attacks on baits, of which 260 were made by a single individual and 124 by more than one. Multiple attacks were the largest source of bycatch of albatrosses (22 of 27 albatrosses whose attacks were observed). Of the baits attacked by albatrosses (n = 244), 17% were indirectly facilitated by diving medium-sized petrels. Considering only the multiple attacks in which albatrosses participated (n = 114), 36% were initiated by these medium-sized petrels. Eleven (41%) of the albatrosses captured, and whose attacks were observed, resulted from a diving medium-sized seabird species first having contacted the terminal tackle. This paper shows that medium-sized petrels, with a strong ability to dive, increase considerably the access to bait, and indirectly, the incidental bycatch of albatrosses. Observations made in the absence of mitigation measures also provide useful information to improve the performance of tori lines. Based on the seabird behaviour, it is recommended that tori lines should have a minimum aerial coverage of 50 m. Copyright © 2012 John Wiley & Sons, Ltd.