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Anthropogenic climate change is resulting in spatial redistributions of many species. We assessed the potential effects of climate change on an abundant and widely distributed group of diving birds, Eudyptes penguins, which are the main avian consumers in the Southern Ocean in terms of biomass consumption. Despite their abundance, several of these species have undergone population declines over the past century, potentially due to changing oceanography and prey availability over the important winter months. We used light-based geolocation tracking data for 485 individuals deployed between 2006 and 2020 across 10 of the major breeding locations for five taxa of Eudyptes penguins. We used boosted regression tree modelling to quantify post-moult habitat preference for southern rockhopper (E. chrysocome), eastern rockhopper (E. filholi), northern rockhopper (E. moseleyi) and macaroni/royal (E. chrysolophus and E. schlegeli) penguins. We then modelled their redistribution under two climate change scenarios, representative concentration pathways RCP4.5 and RCP8.5 (for the end of the century, 2071-2100). As climate forcings differ regionally, we quantified redistribution in the Atlantic, Central Indian, East Indian, West Pacific and East Pacific regions. We found sea surface temperature and sea surface height to be the most important predictors of current habitat for these penguins; physical features that are changing rapidly in the Southern Ocean. Our results indicated that the less severe RCP4.5 would lead to less habitat loss than the more severe RCP8.5. The five taxa of penguin may experience a general poleward redistribution of their preferred habitat, but with contrasting effects in the (i) change in total area of preferred habitat under climate change (ii) according to geographic region and (iii) the species (macaroni/royal vs. rockhopper populations). Our results provide further understanding on the regional impacts and vulnerability of species to climate change.

Summary Seabirds are highly threatened, including by fisheries bycatch. Accurate understanding of offshore distribution of seabirds is crucial to address this threat. Tracking technologies revolutionised insights into seabird distributions but tracking data may contain a variety of biases. We tracked two threatened seabirds (Salvin’s Albatross Thalassarche salvini n = 60 and Black Petrel Procellaria parkinsoni n = 46) from their breeding colonies in Aotearoa (New Zealand) to their non-breeding grounds in South America, including Peru, while simultaneously completing seven surveys in Peruvian waters. We then used species distribution models to predict occurrence and distribution using either data source alone, and both data sources combined. Results showed seasonal differences between estimates of occurrence and distribution when using data sources independently. Combining data resulted in more balanced insights into occurrence and distributions, and reduced uncertainty. Most notably, both species were predicted to occur in Peruvian waters during all four annual quarters: the northern Humboldt upwelling system for Salvin’s Albatross and northern continental shelf waters for Black Petrels. Our results highlighted that relying on a single data source may introduce biases into distribution estimates. Our tracking data might have contained ontological and/or colony-related biases (e.g. only breeding adults from one colony were tracked), while our survey data might have contained spatiotemporal biases (e.g. surveys were limited to waters

Migratory marine species cross political borders and enter the high seas, where the lack of an effective global management framework for biodiversity leaves them vulnerable to threats. Here, we combine 10,108 tracks from 5775 individual birds at 87 sites with data on breeding population sizes to estimate the relative year-round importance of national jurisdictions and high seas areas for 39 species of albatrosses and large petrels. Populations from every country made extensive use of the high seas, indicating the stake each country has in the management of biodiversity in international waters. We quantified the links among national populations of these threatened seabirds and the regional fisheries management organizations (RFMOs) which regulate fishing in the high seas. This work makes explicit the relative responsibilities that each country and RFMO has for the management of shared biodiversity, providing invaluable information for the conservation and management of migratory species in the marine realm., This project has received funding from the European Union’s Horizon 2020 Research and Innovation Programme under the Marie Skłodowska-Curie grant agreement no. 766417. Research made possible with the support, permissions, and funding granted by the following organizations, institutions, and grant agreements: Marine Conservation Program of DPIPWE Tasmania; American Bird Conservancy; Bureau of Ocean Energy Management; communities of Isla Mocha and Islas Juan Fernández; Corporación Nacional Forestal and Servicio Agrícola y Ganadería (Chile); Environment Canada; the National Fish and Wildlife Foundation; the National Geographic Society; ProDelphinus; and the Wallis Foundation; NSF grants DEB 9304579, DEB 9629539, DEB9806606, DEB0235818, and DEB 0842199 to D.J.A.; the National Geographic Society; the U.S. Fish and Wildlife Service; U.S. Geological Survey Ecosystems Mission Area, Wake Forest University; Max-Planck Society and State of Baden-Wuerttemberg Innovation funding; Colorado State University International Programs; Swiss Friends of Galapagos; the International Center for Tropical Ecology at University of Missouri-St. Louis; the Instituto Antartico Chileno (INACH) and the Australian Antarctic Division (AAD); LIFE “Marine IBAs IN Spain” (LIFE04NAT/ES/000049, 2004-2009) and LIFE+ INDEMARES (2009-2014); Sea World Research and Rescue Foundation Inc.; Holsworth Wildlife Research Endowment; and Winifred Violet Scott Trust; FCT-Portugal through projects (UIDB/04292/2020 and UIDP/04292/2020 and UIDP/50017/2020 and UIDB/50017/2020, granted to MARE and CESAM, respectively); the Falklands Islands Government; Natural Environmental Research Council (NERC) core funding to British Antarctic Survey Ecosystems Programme and Official Development Assistance Atlantic Islands project (NE/ R000 107/1); the New Zealand Department of Conservation; Ministry for Primary Industries; Ngāti Rehua Ngāti Wai ki Aotea; Falklands Island Conservation; University of Barcelona (APIF/2015, to M.C.-F.); the French Polar Institute (program IPEV n°109 to H.W.); Réserve Naturelle Nationale des Terres Australes Françaises; and the Zones Atelier Antarctique (LTSER France, CNRS-INEE); European funds through the European Commission Training and Mobility of Researchers Programme (ERBFMBICT983030); Spanish funds through the Ministerio de Ciencia y Tecnología (REN2002-01164/GLO), Ministerio de Educación y Ciencia (CGL2006-01315/BOS), Ministerio de Ciencia e Innovación (CGL2009-11278/BOS), and Ministerio de Economía y Competitividad (CGL2013-42585-P); Catalan funds through the Generalitat de Catalunya (2001SGR00091); and additional funding from SEO/BirdLife (programa Migra & proyecto LIFE+ Indemares), Fundación Banco Bilbao Vizcaya Argentaria (BIOCON04/099) and Fundación Biodiversidad (18PCA4328, 2012-2013); NSERC Discovery Grant and Government of Canada’s Program for International Polar Year to W.A.M.; and an ACAP AC Grant in 2013-14, predoctoral contract BES-2017-079874 of the Spanish Ministerio de Industria, Economía y Competitividad (to L.N.-H.); Spanish Foundation for Biodiversity and Spanish Ministry of Science grant ref. CGL2013-42203-R; the Pew Environment Group via the Pew Fellowship Award in Marine Conservation (to M.L.C.); National Research Foundation; South Africa and Oceans and Coasts; Department of Environment, Agriculture and Fisheries; Malta Seabird Project (LIFE10NAT/MT/090) co-funded by the LIFE program of the European Commission and the Maltese Ministry for the Environment, Sustainable Development and Climate Change, in partnership with the Royal Society for the Protection of Bird and the Portuguese Society for the Study of Birds; predoctoral contract BES-2014-068025 of the Spanish Ministerio de Industria, Economía y Competitividad (to V.M.-P.); Scientific Expert PIM initiative (Petites Iles de Méditerranée); the PIM initiative (Petites Iles de Méditerranée); the Tunisian Coastal Protection and Planning Agency (APAL); Ministry of the Environment, Japan; Funding by Fundación Ecocentro, Argentina; Wildlife Conservation Society, USA; and Ministerio de Ciencia, Tecnología e Innovación, Argentina; Centro Nacional Patagónico (CONICET), postdoctoral contracts by Beatriu de Pinós (2010-BP_A-00173), Juan de la Cierva (JCI-2009-05426), PLEAMAR (2017/2349), and Ramón y Cajal (RYC-2017-22055) programme (to R.R.); Seventh Framework Programme (Research Executive Agency of the European Commission, 618841, FP7-PEOPLE-2013-CIG); Fondation Total pour la Biodiversité (project: Trophic ecology and impacts of bycatch on the avifauna communities of Zembra archipelago); Agence de Protection et d’Aménagement du Littoral (APAL-Tunisia); Killam Postdoctoral fellowship from Dalhousie University; South African National Antarctic Programme; ACAP; Papahānaumokuākea Marine National Monument; NOAA; Japan Society for the Promotion of Science Kakenhi grant 19651100 and 15H02857; National Parks and Conservation Service (Mauritius) (to M.L.C.); IPEV Prog 109; and NASA. The use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. government. The scientific results and conclusions, as well as any views or opinions expressed herein, are those of the authors and do not necessarily reflect those of the NOAA or the Department of Commerce. This communication reflects only the authors’ view, and the Research Executive Agency of the European Union is not responsible for any use that may be made of the information it contains. Z.Z. acknowledges funding from a predoctoral grant (APIF/2012) from the University of Barcelona. J.Ad. acknowledges funding from the U.S. Geological Survey Ecosystems Mission Area, U.S. Bureau of Ocean Energy Management, Pacific OCS Region.

International audience; Ocean circulation connects geographically distinct ecosystems across a wide range of spatial and temporal scales via exchanges of physical and biogeochemical properties. Remote oceanographic processes can be especially important for ecosystems in the Southern Ocean, where the Antarctic Circumpolar Current transports properties across ocean basins through both advection and mixing. Recent tracking studies have indicated the existence of two large-scale, open ocean habitats in the Southern Ocean used by grey petrels (Procellaria cinerea) from two populations (i.e., Kerguelen and Antipodes islands) during their nonbreeding season for extended periods during austral summer (i.e., October to February). In this work, we use a novel combination of large-scale oceanographic observations, surface drifter data, satellite-derived primary productivity, numerical adjoint sensitivity experiments, and output from a biogeochemical state estimate to examine local and remote influences on these grey petrel habitats. Our aim is to understand the oceanographic features that control these isolated foraging areas and to evaluate their ecological value as oligotrophic open ocean habitats. We estimate the minimum local primary productivity required to support these populations to be much

1. The identification of geographic areas where the densities of animals are highest across their annual cycles is a crucial step in conservation planning. In marine environments, however, it can be particularly difficult to map the distribution of species, and the methods used are usually biased towards adults, neglecting the distribution of other life-history stages even though they can represent a substantial proportion of the total population. 2. Here we develop a methodological framework for estimating populationlevel density distributions of seabirds, integrating tracking data across the main life-history stages (adult breeders and non-breeders, juveniles and immatures). We incorporate demographic information (adult and juvenile/immature survival, breeding frequency and success, age at first breeding) and phenological data (average timing of breeding and migration) to weight distribution maps according to the proportion of the population represented by each life-history stage. 3. We demonstrate the utility of this framework by applying it to 22 species of albatrosses and petrels that are of conservation concern due to interactions with fisheries. Because juveniles, immatures and non-breeding adults account for 47%–81% of all individuals of the populations analysed, ignoring the distributions of birds in these stages leads to biased estimates of overlap with threats, and may misdirect management and conservation efforts. Population-level distribution maps using only adult distributions underestimated exposure to longline fishing effort by 18%–42%, compared with overlap scores based on data from all lifehistory stages. 4. Synthesis and applications. Our framework synthesizes and improves on previous approaches to estimate seabird densities at sea, is applicable for data-poor situations, and provides a standard and repeatable method that can be easily updated as new tracking and demographic data become available. We provide scripts in the R language and a Shiny app to facilitate future applications of our approach. We recommend that where sufficient tracking data are available, this framework be used to assess overlap of seabirds with at-sea threats such as overharvesting, fisheries bycatch, shipping, offshore industry and pollutants. Based on such an analysis, conservation interventions could be directed towards areas where they have the greatest impact on populations. Fundação para a Ciência e a Tecnologia - FCT; French Polar Institute IPEV; Falkland Islands Government info:eu-repo/semantics/publishedVersion

Corticosterone (CORT) is a glucocorticoid hormone that maintains energy balance and can modulate foraging behaviors in seabirds. However, CORT responses are not always predictable under similar biophysical conditions and do not necessarily influence the same behaviors across breeding stages and species. To enhance our understanding of CORT's role as a proximate determinant of foraging behavior and energy maintenance, we examined the relationships between body condition, CORT, foraging behavior, and foraging success between two sympatric breeding albatross species with differing foraging strategies and life histories, the Campbell albatross (Thalassarache impavida) and the gray-headed albatross (Thalassarache chrysostoma), from Campbell Island, New Zealand. Pre- and postforaging CORT did not differ between species or stage, potentially as a result of behavioral plasticity or different functional roles of CORT across stages. Unexpectedly, body condition did not correlate with preforaging CORT during incubation, although a negative correlation was observed in Campbell albatrosses during the guard stage. Furthermore, CORT mediated foraging success in both species and stages, but CORT mediated foraging behavior only in incubation-stage Campbell albatrosses that had shorter foraging ranges with higher pretrip CORT. Additionally, CORT positively correlated with mass gain and the time elapsed since the last feeding event in guard-stage albatrosses. Our results highlight the complexity of CORT in mediating energy balance in free-ranging animals. Our results also support that if CORT is to be usefully interpreted, breeding stage must be considered because the physiological and behavioral functionality of CORT may differ across stages, with enhanced sensitivity to energy reserves during chick rearing.

The white-chinned petrel Procellaria aequinoctialis is one of the most frequently observed seabird species captured in fisheries bycatch, yet some populations remain virtually unstudied. The size of the breeding population on the sub-Antarctic Auckland Islands, New Zealand, is unknown. Disappointment Island is thought to be the main white-chinned petrel breeding site in the Auckland Islands, and maybe also in the New Zealand region, and has never had introduced mammalian predators. We estimated the white-chinned petrel breeding population size taking into account the detection probability of burrows via distance sampling and the burrow occupancy rate. Eighty line transects were distributed over the island, with a total line length of 1600 m. Burrows were patchily distributed and most abundant in dense megaherb communities. White-chinned petrel burrow density $$ \hat{D } $$ was 654 burrows/ha (95 % CI 528–809 burrows/ha), with burrow detection probability $$ \hat{p} $$ varying among vegetation communities from 0.28 ± 0.02 to 0.43 ± 0.02 (±SE). Mean burrow occupancy was 0.73 ± 0.03. We document an estimated total of 155,500 (125,600–192,500) breeding pairs of white-chinned petrels on Disappointment Island during mid incubation in early January 2015. The relatively high occupancy and density of burrows suggest that Disappointment Island is a key breeding site for white-chinned petrels.

International audience; Inter-individual variation in behavioural traits has important implications for evolutionary and ecological processes. Site fidelity, where individuals consistently use the same foraging site, is common among marine predators. Sex differences in foraging are also well studied in marine vertebrates, but the extent to which consistent inter-individual differences in foraging vary between the sexes is poorly known. Here we quantify the effects of sex on individual foraging site fidelity (IFSF), both within and between years, in chick brooding Campbell albatross (Thalassarche impavida). Using bird-borne Global Positioning System loggers, we calculated route fidelity (nearest neighbour distance), repeatability of site fidelity (terminal latitude and longitude), and foraging effort (total distance travelled and trip duration) during two to ten repeat trips. Overall, Campbell albatrosses showed a high degree of site fidelity. Birds travelled to similar sites not only within the same year, but also between two consecutive years, suggesting that the within-year consistency is not simply in response to short-term patches of food. Moreover, within the same year there were differences in terms of IFSF between the sexes. Females that foraged closer to the colony in neritic and shelf waters were more likely to follow similar routes on repeated foraging trips and were more consistent in their foraging effort than males. Males that foraged further offshore in pelagic waters had more repeatable foraging longitudes than females. Our study provides further evidence of the importance of IFSF among marine vertebrates. However, it also reveals that the strength of such specialisations may vary with sex.

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.

International audience; Fisheries-related mortality has been influential in driving global declines in seabird populations. Understanding the overlap between seabird distribution and fisheries is one important element in assessing bycatch risk, and may be achieved by tracking the movements of individual birds and fishing vessels. Here, we assess the spatiotemporal overlap between the vulnerable Campbell Albatross Thalassarche impavida and large (>28 m) commercial fishing boats in New Zealand’s Exclusive Economic Zone (EEZ). We used a novel analytical approach, bivariate Gaussian bridge movement modelling, to compute spatiotemporal utilization distributions of bird-borne global positioning system (GPS) loggers and data from the Vessel Monitoring System. We tracked birds for 28,815 h during incubation and chick brooding, with half of this time spent within New Zealand’s EEZ, utilizing 6.7% of the available area. However, there was no evidence that albatrosses and fishing vessels were in the same location simultaneously. We accounted for the broader ecological footprint of fishing vessels by calculating the distance between GPS-fix locations for albatrosses and fishing vessels, revealing that albatrosses were within 30 km of fishing vessels in 8.4% of foraging trips. This highlights differences in estimated fine-scale spatiotemporal overlaps which may be due to the distance between albatrosses and vessels or the methods used. Overall, the low levels of spatial overlap could be a result of Campbell Albatross’ preference for foraging in areas without fishing activity or competitive exclusion by other species. Our results reinforce the importance of multi-scale, temporally explicit, and multi-national approaches to risk assessment, as Campbell Albatrosses spend approximately half of their time foraging outside New Zealand’s EEZ.

Major population changes of marine mega-fauna are ongoing as global warming, and other anthropogenic drivers affect prey availability. The historical stronghold of the Eastern Rockhopper Penguin (Eudyptes chrysocome filholi) was New Zealand’s sub-Antarctic Campbell Island, but the population declined by 94 % between 1942 and 1984. The apparent mechanism of collapse was warm ocean temperatures causing an inadequate food supply. Eudyptes penguin population declines are ongoing at some breeding sites, highlighting the need to investigate the population trend on Campbell Island since 1984. We estimated the Eastern Rockhopper Penguin breeding population size through physical and photo-counts of birds and nests in 2012, and changes in colony area relative to 1984 and 1996 photographs. We estimated the 2012 population size at 33,239 breeding pairs, a 21.8 % decrease from an (adjusted) estimate of 42,528 pairs in 1984. Although substantial, the recent 1984–2012 decline occurred at a much slower rate (λ = 0.991) than the 1942–1984 decline (λ = 0.940). Despite great variation in trends between colonies ostensibly linked to differences in predation rates, the recent decline occurred primarily between 1984 and 1996, and thereafter the overall population grew. A 100-year time series of extended reconstructed sea surface temperatures (ERSST) confirmed that the population declined during warm periods and increased during cool periods, but that the initial decline began before increases in regional ERSST. Population growth after 1996 appears related to the current global warming hiatus, lower ERSST, and increased abundance of a key prey species. We predict a continuation of the long-term population decline after warming resumes.

Croxall et al. (2013; Mar Ecol Prog Ser 493:297-300) assert that fine-scale analysis of seabird-fisheries overlap, such as that presented in Torres et al. (2013; Mar Ecol Prog Ser 473:275-289), is of limited value for the assessment and management of seabird bycatch. In contrast, we consider that the highly dynamic movement patterns of both seabirds and fishing vessels necessitate analyses at multiple scales to fully understand the spatio-temporal variation in their associations. Conservation management of seabird bycatch in fishing operations can be applied at multiple scales from large ocean basins to small sub-national management units. We argue that the appropriate scale of analysis of seabird−fishery overlap is dependent on the data available and on the scale of management to be applied. The criticism by Croxall et al. (2013) of our analytical methods and interpretation of results does not affect the derived rates of overlap between Buller’s albatrosses and fishing vessels. Studies of seabird-fisheries overlap at all scales are trending toward analyses at smaller spatial and temporal scales, supporting the conclusion of Torres et al. (2013) that scaling down such analyses is valuable for improving our ecological understanding of seabird-fishery associations and for the conservation management of seabird bycatch.

Seabird-fishery interactions are currently a major issue in marine conservation management. A common approach to quantifying the extent of interactions is to overlay density maps of seabird and fishing activities derived from point locations. Such large-scale evaluations of overlap can be misleading due to the static representation of birds and vessels that in reality are spatially and temporally dynamic. Additionally, overlap at large scales does not necessarily indicate interaction; overlapping distributions of seabirds and fisheries could reflect coincident use of habitat. Using 4 yr of distribution data, we conducted a fine-scale analysis of overlap between albatrosses and fishing vessels. Results were compared to those derived from large-scale density comparisons. Additionally, we compared overlap versus interaction rates by calculating the proportion of time that birds foraged in close association with a fishing vessel versus independently while within 10 km of a vessel. Results of our fine-scale analysis indicated generally low rates of overlap while foraging and high variability among sexes, years and types of fishery. Changes in overlap rates were attributed to shifts in both albatross and vessel distributions. Albatrosses foraged independently of fishing vessels half the time they were within 10 km of a vessel, indicating that 50% of overlap is due to coincident habitat use rather than vessel interaction. Overlaying of large-scale distribution maps failed to distinguish annual variation in the degree of bird-fishery overlap, and suggested overlap where none was identified at the finer scale. This study illustrates the increased insight derived from fine-scale analyses of seabird-fisheries interactions.

Petrels are highly mobile seabirds that face many threats and whose conservation is frequently hampered by a lack of understanding of their biology at sea. We used a combination of data from burrow monitoring and geolocation-immersion loggers to study the intra- and inter-seasonal distribution and behaviour of the endangered Chatham Petrel (Pterodroma axillaris), breeding on Rangatira Island, New Zealand. Breeding extended from November to June with a pre-laying exodus of 35 days; an incubation period of 46 days, with up to five incubation shifts; and a chick-rearing period of 87 days, including a desertion period of 10 days. When breeding, Chatham Petrels foraged between the Subtropical Convergence and Subantarctic Fronts, moving 2000–3000 km to the south-east of the Chatham Islands, during the pre-laying exodus and incubation period, but restricting foraging to the south of the Chatham Islands, around the Bollons Seamount, during chick-rearing. Between April and June birds migrated east and north to core non-breeding distributions ~1000 km from the coast of Peru and Chile. Birds spent a greater proportion of time resting and nocturnally active during the non-breeding period than when breeding, when birds where active during darkness and daylight. These data contribute to the conservation management of the Chatham Petrel and to conservation initiatives to identity marine protected areas for endangered seabirds on the high seas beyond national jurisdictions.

Many albatross populations are declining and a major cause is believed to be incidental mortality from fishing. We investigated the effect of fishing on southern Buller's albatross Thalassarche bulleri bulleri, using a new approach to seabird population modelling that allows estimation of demographic parameters from multiple data types. Three types of data were used: a 60-year set of mark–recapture observations, four censuses of the breeding population, and estimates of fishing effort and bycatch. The fisheries risk to the viability of this population over the last 60 years appears to have been small, since the adult population is estimated to have increased about five-fold over that time. There is some cause for concern in recent changes (population growth has slowed, and perhaps reversed, and adult survival rates are falling). The most common age at first breeding was 12 years, and about 80% of adults breed each year. Annual survival was estimated to be 0.91 for juveniles, and varied between th...

Incidental bycatch of seabirds in commercial fishing activities is known to cause declines in seabird populations. However, the full impacts on the ecology of seabirds, including effects on seabird distribution and behavior, through the association with fisheries are not fully understood. We developed a novel method to integrate fine-scale GPS tracking data from the foraging trips of 25 white-capped albatross Thalassarche steadi within sub-Antarctic New Zealand with fishing effort distribution data to (1) quantify fine-scale overlap between individual albatrosses and individual vessels and (2) characterize behavioral changes in albatrosses when they are associated with fishing vessels. Overlap between vessels and albatrosses occurred in 68% of tracks. However, albatrosses demonstrated high variability in foraging trip destinations and association rates with fishing activity, both between and within individuals. Eight tracks never overlapped a fishing vessel. Of the 17 tracks that did overlap, a range of 2 to 73% of foraging effort on each trip occurred while overlapping a fishing vessel. Albatross foraging behavior was characterized by a significantly slower and straighter path when overlapping vessels. This study highlights the utility of GPS tags to examine the fine-scale distribution of seabirds in relation to fishing activity, revealing how effects of fisheries on marine megafauna may extend beyond mortality and injury as well as population numbers. However, results are currently constrained, not only by limited tracking data sets, but also by the quality (spatiotemporal resolution) and availability of fishing effort data. Critical conservation issues related to the effects of fisheries on threatened marine megafauna cannot be fully addressed without comparative data sets with resolution equal to GPS tags.

The flesh-footed shearwater Puffinus carneipes is a medium-sized shearwater and transequatorial migrant within the Pacific Ocean. We used archival data loggers to study the non-breeding migration and diving behaviour of three flesh-footed shearwaters following breeding in New Zealand. In early April, the birds migrated to the western North Pacific Ocean in 23±2 days, occupying core distributions within the Kuroshio/Oyashio transition system for 91±17 days. Subsequent movements were made into the Sea of Okhotsk prior to return migrations to New Zealand in mid September (19±1 days). Diving depths during migration (2.5±2.4 m), and in the western North Pacific (2.4±2.6 m) were shallower than during the onset of breeding (4.8±8.7 m). Non-breeding flesh-footed shearwaters occupy a region of high fisheries activity and the impact of these fisheries on adult survival in this declining species warrant further study.

The numbers of Black-browed Albatrosses Diomedea melanophrys and Grey-headed Albatrosses D. chrysostoma at Campbell Island, New Zealand, have declined dramatically since the 1940s. Black-browed Albatross numbers went into a steep decline in the 1970s and, since at least 1984, have been increasing slightly at average rates of 1.1% and 2.1% per annum at two colonies. The long-term downward trend in numbers of the Grey-headed Albatross has continued into the 1990s, averaging annually between 3.0% and 4.8% per annum at different colonies. A demographic study carried out between 1984 and 1996 indicates that Black-browed and Grey-headed Albatrosses have similarly high annual adult survival rates (0.945 and 0.953, respectively). Black-browed Albatrosses breed for the first time at a younger average age than do Grey-headed Albatrosses (10 years and 13.5 years, respectively), have a higher average breeding success (0.663 compared with 0.397 for the latter species) and are annual breeders whereas Greyheaded Albatross show a typical biennial pattern of breeding. Both show low survival from fledging to first breeding; averaging 0.186 and 0.162 for Black-browed and Grey-headed Albatrosses, respectively. Both species are accidentally killed in the Japanese long-line fishery for tuna Thunnus sp. in the Australasian region. The steep decline of Black-browed Albatross numbers in the 1970s was concomitant with the development of this fishery in the foraging region of the Campbell Island birds. Currently, the slight increase in numbers is due to high adult survival rates and breeding success, and is coincident with a great reduction in long-line fishing. With stable and high adult survival rates, it is expected that future population trends will be mainly influenced by the recruitment rates. The continuous decline in Grey-headed Albatross numbers since the 1940s, before long-line fishing developed in this region, indicates that natural environmental processes contributed to the downward trend in breeding numbers. Modelling indicates that Grey-headed Albatross numbers will continue to decrease with the present demographic parameters. A comparison between the species breeding at different sites shows that differing environmental conditions influence demographic characteristics.

International audience; Species distribution models (SDMs) are increasingly applied in conservation management to predict suitable habitat for poorly known populations. High predictive performance of SDMs is evident in validations performed within the model calibration area (interpolation), but few studies have assessed SDM transferability to novel areas (extrapolation), particularly across large spatial scales or pelagic ecosystems. We performed rigorous SDM validation tests on distribution data from three populations of a long-ranging marine predator, the grey petrel Procellaria cinerea, to assess model transferability across the Southern Hemisphere (25-65°S). Oceanographic data were combined with tracks of grey petrels from two remote sub-Antarctic islands (Antipodes and Kerguelen) using boosted regression trees to generate three SDMs: one for each island population, and a combined model. The predictive performance of these models was assessed using withheld tracking data from within the model calibration areas (interpolation), and from a third population, Marion Island (extrapolation). Predictive performance was assessed using k-fold cross validation and point biserial correlation. The two population-specific SDMs included the same predictor variables and suggested birds responded to the same broad-scale oceanographic influences. However, all model validation tests, including of the combined model, determined strong interpolation but weak extrapolation capabilities. These results indicate that habitat use reflects both its availability and bird preferences, such that the realized distribution patterns differ for each population. The spatial predictions by the three SDMs were compared with tracking data and fishing effort to demonstrate the conservation pitfalls of extrapolating SDMs outside calibration regions. This exercise revealed that SDM predictions would have led to an underestimate of overlap with fishing effort and potentially misinformed bycatch mitigation efforts. Although SDMs can elucidate potential distribution patterns relative to large-scale climatic and oceanographic conditions, knowledge of local habitat availability and preferences is necessary to understand and successfully predict region-specific realized distribution patterns.

Genetic variability in the only two existing populations of Buller's albatross (Thalassarche bulleri bulleri) was assessed using six polymorphic microsatellite loci. Large biological samples were obtained from both the Snares (n = 99) and the Solander Islands (n = 27). Several measures of genetic differentiation including F(ST) and R(ST) and a principal coordinates analysis (PCO) suggest a complete absence of genetic structure between three breeding colonies on the Snares Islands, and between them and one breeding colony on the Solander Islands. Mark/recapture studies of recently banded albatross chicks on the Snares found high natal philopatry in T. b. bulleri, but the microsatellite DNA data suggest that sufficient gene flow still occurs between all four breeding colonies to maintain a genetically homogeneous population overall.

The abundance and distribution of the southern subspecies of Buller’s Albatross (Thalassarche b. bulleri) breeding on the Solander and Snares Islands were investigated during February–March 2002. At the Solander Islands, a total of 4912 breeding pairs was estimated from aerial and ground counts. This total compares to an adjusted total of 4147 breeding pairs estimated during February 1996 using the same methods, and indicates average annual increases of 3.1% during the period 1996–2002, compared with relatively stable numbers estimated for the period 1985–96. At the Snares Islands, a total of 8165 breeding pairs was counted on North East Island and associated islets from ground and vantage-point counts, and 8713 breeding pairs were estimated for the Snares Islands as a whole. Analysis of annual counts of breeding pairs on the North Promontory of North East Island showed an estimated increase in the breeding population of 3.2% per year. In 2002, the estimated total breeding population of Buller’s Albatross at the Snares and Solander Islands was 13 625 pairs.

The effect of minimum maternal experience, individual and year on egg size variation, breeding success and sex of the surviving chick were investigated in Buller's albatrosses (Thalassarche bulleri) breeding at the Snares Islands. Minimum maternal experience and individual effects were studied over the 9 years 1996–2004, while a second set of data allowed inter‐annual variation in egg size to be investigated over 4 additional years (1961, 1969, 1970, and 1993). Egg length, breadth, volume and eccentricity did not vary between years, but all four variables varied significantly between individuals. The size of eggs laid by one individual varied less than the variation across the population as a whole. Egg volume increased with minimum maternal breeding experience, mainly because eggs became broader but not longer, up to the fourth breeding attempt. There was a weak positive relationship between egg size and breeding success, but this correlation was confounded by maternal breeding experience. Breed...

Summary 1 A spatially explicit, individual-based population model (IBPM) for southern Buller's albatross Thalassarche bulleri bulleri was developed to simulate the species’ at-sea distribution and interactions with fishing fleets. 2 Satellite tracking data for birds from colonies on Snares Islands and Solander Island (south of South Island, New Zealand) suggest that the feeding grounds utilized by a bird, and the duration of its foraging trips, are dependent upon colony, sex, pairing status and developmental stage of egg/chick. These dependencies were incorporated into the IBPM. 3 Simulated distributions were compared with independent shipboard observations by using the IBPM to make replicated ‘virtual counts’ corresponding to each shipboard count. Each shipboard count was assigned a score reflecting the likelihood that a count of this magnitude would have arisen if the true populations behave as described by the IBPM. 4 Randomization tests indicated that, for the months in which we had adequate telemetry data (March–July), predicted and observed distributions were very similar at scales down to 1 degree2. There was some evidence that bird densities around the south-west corner of New Zealand's South Island were underpredicted in July, and at the scale of individual shipboard counts the ship data showed greater fine-scale aggregation than the virtual data. 5 Comparison of observed and simulated distributions early in the breeding season (January and February, for which we had no telemetry data) suggested that the foraging behaviour of birds prior to egg laying differs from that exhibited by either breeding or pre-breeding birds later in the season. 6 Synthesis and applications. In combination with reported by-catch rates, our IBPM may enable us to derive fishing gear-specific per-capita capture rates for Buller's albatross. Our results also emphasize that it may be necessary to represent responses of individual birds encountering vessels at a finer spatiotemporal scale before it will be possible to make robust demographic predictions of the consequences of changes in fishing practices.

International audience; Species in comparative demography studies often have a common phylogenetic or evolutionary ancestry and hence, they cannot fully be treated as independent samples in the statistical analysis. Although the serious implication of ignoring phylogeny has long been recognized, no attempt has been made so far to account for the lack of statistical independence due to phylogeny in multi-species mark-recapture comparative demography studies. In this paper, we propose a Bayesian hierarchical model that explicitly accounts for phylogenetic dependence among species, and to correct for imperfect detection, which is a common phenomenon in free-ranging species. We illustrate the method using individual mark-recapture data collected from 16 seabird species of the order Procellariiformes. Data on body mass and phylogeny of these species are compiled from literature. We investigate the relationship between adult survival and body mass with and without accounting for phylogeny. If we ignore phylogeny, we obtain a positive survival-body mass relationship. However, this relationship is no longer statistically significant once phylogenetic dependence is taken into account, implying that survival may actually depend on an unmeasured variable that is correlated with body mass due to a shared dependence on phylogeny. The proposed model allows the integration of multi-species mark-recapture data and phylogenetic information, and it is therefore a valuable tool in ecological and evolutionary biology.

To compensate for drift, an animal migrating through air or sea must be able to navigate. Although some species of bird, fish, insect, mammal, and reptile are capable of drift compensation, our understanding of the spatial reference frame, and associated coordinate space, in which these navigational behaviors occur remains limited. Using high resolution satellite-monitored GPS track data, we show that juvenile ospreys (Pandion haliaetus) are capable of non-stop constant course movements over open ocean spanning distances in excess of 1500 km despite the perturbing effects of winds and the lack of obvious landmarks. These results are best explained by extreme navigational precision in an exogenous spatio-temporal reference frame, such as positional orientation relative to Earth's magnetic field and pacing relative to an exogenous mechanism of keeping time. Given the age (

Pelagic seabirds spend most of their time foraging at sea far from their breeding grounds. Yet most information on their ecology comes from land-based studies, and the need for studies on their foraging ecology has been recognised as of prime importance to an understanding of their extreme life history traits (Ricklefs 1990). Recently, such studies have been made possible for large seabirds such as albatrosses with the development of satellite telemetry (Jouventin and Weimerskirch 1990). However, most studies have concentrated on the largest of the albatross species (e.g., Prince et al. 1992, Weimerskirch et al. 1993, Nicholls et al. 1994), with only one on a smaller species, the Lightmantled Sooty Albatross Phoebetria palpebrata (Weimerskirch and Robertson 1994). No studies have been published on mollymawks, the subfamily with the greatest number of species. Buller's Albatrosses (Diomedea bulleri) are endemic to New Zealand, where the Southern subspecies (D. b. bulleri) breeds at The Snares and the Solander Islands, and the Northern subspecies (D. b. platei) at the Chatham and Three Kings Islands (Turbott 1990). Their distribution at sea is poorly known, although the pelagic range is across the Southern Pacific Ocean, north of the Antarctic Convergence from southeastern Australia to Chile and Peru (Marchant and Higgins 1990). Movements of adults are also poorly known, and Marchant and Higgins (1990) suggested that they may move only locally. An examination of 27 regurgitations from adults and chicks collected on The Snares and the Chatham Islands (West and Imber 1986) indicated that the diet comprised mainly species which occur within the New Zealand region. However, Richdale (1949) showed that incubation spans of birds on The Snares ranged up to 21 days, indicating that these birds could forage long distances form the breeding colonies. Substantial mortality of Southern Buller's Albatrosses has been reported to occur as a result of commercial fisheries southwest of New Zealand (Bartle 1991, Murray et al. 1993), so knowledge of the foraging zones of the subspecies has important implications for conservation. We used satellite telemetry to determine the foraging movements during late incubation of Southern Buller's Albatrosses breeding at The Snares.

Pelagic seabirds are highly mobile, reducing the likelihood of allopatric speciation where disruption of gene flow between populations is caused by physically insurmountable, extrinsic barriers. Spatial segregation during the non-breeding season appears to provide an intrinsic barrier to gene flow among seabird populations that otherwise occupy nearby or overlapping regions during breeding, but how this is achieved remains unclear. Here we show that the two genetically distinct populations of Cook's petrel (Pterodroma cookii) exhibit transequatorial separation of non-breeding ranges at contemporary (ca. 2-3 yrs) and historical (ca. 100 yrs) time scales. Segregation during the non-breeding season per se appears as an unlikely barrier to gene flow. Instead we provide evidence that habitat specialization during the non-breeding season is associated with breeding asynchrony which, in conjunction with philopatry, restricts gene flow. Habitat specialization during breeding and non-breeding likely promotes evolutionary divergence between these two populations via local adaptation.

International audience; BACKGROUND: Sooty (Puffinus griseus) and short-tailed (P. tenuirostris) shearwaters are abundant seabirds that range widely across global oceans. Understanding the foraging ecology of these species in the Southern Ocean is important for monitoring and ecosystem conservation and management. METHODOLOGY/PRINCIPAL FINDINGS: Tracking data from sooty and short-tailed shearwaters from three regions of New Zealand and Australia were combined with at-sea observations of shearwaters in the Southern Ocean, physical oceanography, near-surface copepod distributions, pelagic trawl data, and synoptic near-surface winds. Shearwaters from all three regions foraged in the Polar Front zone, and showed particular overlap in the region around 140 degrees E. Short-tailed shearwaters from South Australia also foraged in Antarctic waters south of the Polar Front. The spatial distribution of shearwater foraging effort in the Polar Front zone was matched by patterns in large-scale upwelling, primary production, and abundances of copepods and myctophid fish. Oceanic winds were found to be broad determinants of foraging distribution, and of the flight paths taken by the birds on long foraging trips to Antarctic waters. CONCLUSIONS/SIGNIFICANCE: The shearwaters displayed foraging site fidelity and overlap of foraging habitat between species and populations that may enhance their utility as indicators of Southern Ocean ecosystems. The results highlight the importance of upwellings due to interactions of the Antarctic Circumpolar Current with large-scale bottom topography, and the corresponding localised increases in the productivity of the Polar Front ecosystem.

Electronic tracking tags have revolutionized our understanding of broad-scale movements and habitat use of highly mobile marine animals, but a large gap in our knowledge still remains for a wide range of small species. Here, we report the extraordinary transequatorial postbreeding migrations of a small seabird, the sooty shearwater, obtained with miniature archival tags that log data for estimating position, dive depth, and ambient temperature. Tracks (262 ± 23 days) reveal that shearwaters fly across the entire Pacific Ocean in a figure-eight pattern while traveling 64,037 ± 9,779 km roundtrip, the longest animal migration ever recorded electronically. Each shearwater made a prolonged stopover in one of three discrete regions off Japan, Alaska, or California before returning to New Zealand through a relatively narrow corridor in the central Pacific Ocean. Transit rates as high as 910 ± 186 km·day −1 were recorded, and shearwaters accessed prey resources in both the Northern and Southern Hemisphere’s most productive waters from the surface to 68.2 m depth. Our results indicate that sooty shearwaters integrate oceanic resources throughout the Pacific Basin on a yearly scale. Sooty shearwater populations today are declining, and because they operate on a global scale, they may serve as an important indicator of climate change and ocean health.

Genetic variability in the only two existing populations of Buller's albatross (Thalassarche bulleri bulleri) was assessed using six polymorphic microsatellite loci. Large biological samples were obtained from both the Snares (n = 99) and the Solander Islands (n = 27). Several measures of genetic differentiation including F(ST) and R(ST) and a principal coordinates analysis (PCO) suggest a complete absence of genetic structure between three breeding colonies on the Snares Islands, and between them and one breeding colony on the Solander Islands. Mark/recapture studies of recently banded albatross chicks on the Snares found high natal philopatry in T. b. bulleri, but the microsatellite DNA data suggest that sufficient gene flow still occurs between all four breeding colonies to maintain a genetically homogeneous population overall.

The marine habitat exploited by black-browed Diomedea melanophrys and grey-headed albatrosses D. chrysostoma breeding at Campbell Island, New Zealand, was studied using satellite telemetry. Data were analysed in relation to the bathymetry and sea-surface temperature of the foraging zones. Black-browed albatrosses spent 55% of their time on the Campbell Plateau but also carried out long foraging trips to the Polar Front and Antarctic Zone at a distance of over 2000 km. They relied heavily on juvenile Micromesistius australis, a schooling fish, during foraging trips to the shelf but over oceanic waters the squid Martialia hyadesi was the main prey taken. Grey-headed albatrosses spent 71% of their time foraging over the deep waters of the Polar Frontal Zone where M. hyadesi comprised over 90% of the mass of prey taken. No satellite-tracked birds fed over the shelf, but data from the duration of foraging trips and dietary analysis suggests that shelf-feeding is important for this species. Significant inter-species differences in the time spent in neritic and oceanic zones show that black-browed albatrosses are reliant primarily on shelf resources while grey-headed albatrosses are primarily oceanic feeders. In addition, the 2 species overlapped little in the zones used over oceanic waters, with black-browed albatrosses feeding in more southerly waters than grey-headed albatrosses. However, both species feed on M. hyadesi when foraging in association with the Polar Front.

To determine the extent of prey selection by the nocturnally active fish Galaxias vulgaris, samples of fish, drift, and benthos were collected over a 24‐h period in summer in a stream draining the foothills of the Southern Alps in New Zealand. Feeding started after sunset, peaked by midnight, and virtually ceased by midday. Both drifting and benthic foods were consumed, and timing of peak feeding was synchronous with the period of greatest abundance of aquatic drift. Larvae of Austrosimulium spp., Deleatidium spp., and Aoteapsyche colonica comprised the major proportion of the prey eaten. Prey selection was indicated by the over‐representation of Austrosimulium spp. and under‐representation of both the smaller size classes of Deleatidium spp. and other aquatic invertebrates in the diet of fish. With the exception of the coleopteran Costelytra zelandica, terrestrial organisms were not eaten by fish, but several aquatic taxa were. Foraging by Galaxias vulgaris on drift and benthos may provide fish ...