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Sooty Tern, Onychoprion fuscatus (Linnaeus 1766), is a rare species along the Brazilian coast due to oceanic habits. We report the first documented record of this species from São Paulo state, southeastern Brazil. The specimen was found beached in Mongaguá municipality. Morphological assessment, necropsy, and histological analysis allowed us to identify species, reproductive state (non-breeding), and sex (male) of this specimen. [ABSTRACT FROM AUTHOR]

Animal migration is a major driver of infectious agent dispersal. Duck and seabird migrations, for instance, play a key role in the spatial transmission dynamics and gene flow of avian influenza viruses (AIV), worldwide. On tropical islands, brown and lesser noddies (Anous stolidus and Anous tenuirostris) may be important AIV hosts, but the lack of knowledge on their migratory behaviour limits our understanding of virus circulation in island networks. Here we show that high connectivity between islands generated by non-breeding dispersive behaviours may be a major driver in the spread and the maintenance of AIV among tropical islands of the western Indian Ocean. Tracking data highlight two types of dispersive behaviours during the non-breeding season: birds either staying in the vicinity of their breeding ground (on Bird Island, Seychelles), or moving to and roosting on other islands in the western Indian Ocean. Migrant birds used a wide range of roosting places from the Tanzanian coasts to the Maldives archipelago and Tromelin Island. Epidemiological data confirm that brown and lesser noddies are major hosts for AIV, although significant variations of seroprevalence between species suggest that other biological and ecological drivers could be involved in virus infection and transmission dynamics.

Summary: Plastic pollution affects marine ecosystems worldwide and poses risks for seabirds. Most recorded impacts on organisms are negative but, in some cases, the constructive use of plastic fragments or objects by birds has also been recorded. Small blue and green plastic fragments are found scattered among nests in a large (c.500,000 pairs) Sooty Tern Onychoprion fuscatus nesting colony on Bird Island, Seychelles. We investigated whether the fragments were being imported by the birds, and if so whether import was accidental or intentional. We found that Sooty Terns were the only seabird species to have plastic fragments in their nesting area and import of fragments varied seasonally and spatially. Throughout the colony, plastic fragments were imported during egg-laying, incubation, and chick-rearing, but import declined as chicks began to fledge. A part of the colony where all eggs were harvested for human consumption received more fragments than among undisturbed nests. We failed to find evidence of ingestion and excretion of fragments and suggest other avenues for investigation. [ABSTRACT FROM AUTHOR]

In the face of accelerating ecological change to the world's oceans, seabirds are some of the best bio‐indicators of marine ecosystem function. However, unravelling ecological changes that pre‐date modern monitoring programmes remains challenging. Using stable isotope analysis of feathers and regurgitants collected from sooty terns (Onychoprion fuscatus) nesting at a major Atlantic colony, we reconstructed a long‐term dietary time series from 1890 to the present day and show that a significant dietary shift occurred during the second half of the twentieth century coinciding with an apparent population collapse of approximately 84%. After correcting for the "Suess Effect," δ13C in feathers declined by ~1.5‰ and δ15N by ~2‰ between the 1890s and the present day, indicating that birds changed their diets markedly over the period of population decline. Isotopic niches were equally wide before and after the population collapse but isotopic mixing models suggest that birds have grown ever more reliant on nutrient‐poor squid and invertebrates as teleost fish have declined in availability. Given that sooty terns rely heavily on associations with sub‐surface predators such as tuna to catch fish prey, the rapid expansion of industrialized fisheries for these species over the same period seems a plausible mechanism. Our results suggest that changes to marine ecosystems over the past 60 years have had a dramatic impact on the ecology of the most abundant seabird of tropical oceans, and highlight the potentially pervasive consequences of large predatory fish depletion on marine ecosystem function. We estimated contributions of each of the four main prey groups (teleost fish species [false halfbeaks, blue flying fishes, redlip blennies and Simony's frostfishes], squid [Teuthida], marine invertebrates [Sally Lightfoot crabs and violet sea snails] and terrestrial invertebrates [locust species]) in the diet of sooty terns breeding on Ascension Island in the South Atlantic. Their diet has changed markedly in decades (a) before and (b) after their population collapsed by 84% over approximately a 30‐year period. [ABSTRACT FROM AUTHOR]

We isolate and characterise 16 polymorphic microsatellite loci for the super-abundant, pan-tropical sooty tern (Onychoprion fuscatus), facilitating population genetic studies. In 70 samples from two breeding colonies, the total number of alleles per locus ranged between 5 and 21, observed heterozygosity ranged from 0.143 to 0.942, while estimated null allele frequency varied from −0.131 to 0.273. Polymerase chain reaction (PCR) conditions were optimised across loci, enabling multiplexing and rapid multilocus genotyping. These 16 loci will be useful for future studies of genetic diversity and population structure, and can be used as a proxy through which to assess ecosystem function and change. We additionally test cross-species amplification in the brown (Anous stolidus) and lesser (A. tenuirostris) noddies, illustrating a use of these microsatellites in other related Sternidae species. [ABSTRACT FROM AUTHOR]

Migration is a fundamental aspect of the ecology and evolutionary history of many animals, driven by seasonal changes in resource availability and habitat structure. Seabird migration has been investigated extensively in highly seasonal temperate and polar environments. By contrast, the relationships between migration and seasonal environmental changes have rarely been studied in tropical marine habitats. The sooty tern Onychoprion fuscatus is the most abundant tropical seabirds, and has been ranked as the most important tropical species in terms of its annual estimated consumption of marine resources. We used global location sensing (GLS loggers) to describe for the first time the year-round at-sea distribution and activity patterns of sooty terns from a large breeding colony in the western Indian Ocean (Bird Island, Seychelles). While breeding, they foraged within 1,074 ± 274 km of the colony. After breeding, birds undertook an extensive post-breeding migration throughout the Indian Ocean; average distances traveled exceeded 50,000 km per individual. Sooty terns used mainly four distinct core oceanic areas during the non-breeding period; in the Bay of Bengal (A), northeast to an area straddling the Chagos-Laccadive plateau (B), southeast to an area on each side of the 90 East Ridge (C) and southwest to an area around Comoros (D). Individuals exhibited a high degree of fidelity to these core areas in successive years. We also established that they performed an unusual behavior for a non-Procellariiformes seabird; most individuals undertook a 1-month pre-laying exodus, during which they foraged in a specific area c. 2,000 km to the south-east of the colony. Year-round at-sea activity of sooty terns revealed that they spent only 3.72% of their time in contact with seawater, so indicating that they must sleep in flight. Activity parameters exhibited seasonal (breeding vs. non-breeding periods) and daily variations; they notably never land on the water at night. In the Seychelles, breeding sooty terns are threatened by commercial egg harvesting. Our discovery of extremely wide non-breeding at-sea distribution highlights the risk of other threats during their non-breeding period, such as over-fishing, marine pollution and climate change.

Animal migration is a major driver of infectious agent dispersal. Duck and seabird migrations, for instance, play a key role in the spatial transmission dynamics and gene flow of avian influenza viruses (AIV), worldwide. On tropical islands, brown and lesser noddies ( Anous stolidus and Anous tenuirostris ) may be important AIV hosts, but the lack of knowledge on their migratory behaviour limits our understanding of virus circulation in island networks. Here we show that high connectivity between islands generated by non-breeding dispersive behaviours may be a major driver in the spread and the maintenance of AIV among tropical islands of the western Indian Ocean. Tracking data highlight two types of dispersive behaviours during the non-breeding season: birds either staying in the vicinity of their breeding ground (on Bird Island, Seychelles), or moving to and roosting on other islands in the western Indian Ocean. Migrant birds used a wide range of roosting places from the Tanzanian coasts to the Maldives archipelago and Tromelin Island. Epidemiological data confirm that brown and lesser noddies are major hosts for AIV, although significant variations of seroprevalence between species suggest that other biological and ecological drivers could be involved in virus infection and transmission dynamics., Competing Interests: The authors declare that they have no competing interests., (© 2023 The Authors.)

Foraging ranges of incubating Sooty Terns Onychoprion fuscatus on Bird Island, Seychelles, during a transition from food plenty to scarcity, as revealed by GPS loggers. Marine Ornithology 46: 11-18. The foraging tracks of incubating Sooty Terns, nesting on Bird Island, Seychelles, were identified using global positioning system (GPS) loggers attached to the central pair of rectrices. By chance, our 2014 study covered a transition from food abundance to shortage. Incubation shifts during food abundance were mainly 1-2 d long but, at the height of food shortage, ranged from 4 d to 13 d, leading to temporary and permanent nest desertion by individuals left caring for the egg. The duration of foraging trips and the distance travelled also increased, from 151 km to 271 km for birds absent for 1-3 d, to 2 142-2 779 km by birds that were away from the colony for 4-10 d. This technique, coupled with spatial analyses that relate track paths and foraging locations to bathymetry, sea surface temperature, and chlorophyll levels, permitted more detailed investigations of the breeding birds' use of their oceanic habitats. It also provided data to support and define areas to be recommended for Marine Protected Area status in Seychelles and elsewhere. [ABSTRACT FROM AUTHOR]

Seabirds have suffered dramatic declines in population over recent decades. The most abundant seabirds of tropical oceans are Sooty Terns Onychoprion fuscatus and they have an IUCN Red List category of 'Least Concern'. Ascension Island has the largest colony of Sooty Terns in the Atlantic Ocean and censuses between 1990 and 2013 have shown that its population size is static. In this study we have used historical data and recent censuses to describe the population status of Sooty Terns on Ascension Island over a century. We show that the breeding population contained over 2 million individuals in the 1870s and remained at this level for at least 70 years. However, the population declined from >2 million birds in 1942 to 350,000 birds by 1990. The population trend spanning a period equivalent to three generations of the species (63 years; 1942-2005) showed an approximate 84% decline in population size. Using IUCN criteria this suggests that Sooty Terns on Ascension could be considered 'Critically Endangered'. We conclude that a re-evaluation of Sooty Tern conservation status is necessary at the local level and possibly globally. Our study highlights that for long-lived species historic demographic data should be considered when determining conservation status. [ABSTRACT FROM AUTHOR]

Common Mynas Acridotheres tristis were introduced to the small, isolated barren island of Ascension in the tropical Atlantic Ocean in the 1880s. The founder population of 52 pairs increased at a rate of 2 % per annum. Mynas cause egg losses in other species by puncturing and consuming eggs, puncturing eggs with no consumption or displacing incubating birds that then desert viable eggs. The principal target seabirds of Mynas on Ascension Island are Sooty Terns Onychoprion fuscatus which number 388,000 birds and constitute 97 % of all seabirds on the island. Five censuses of Mynas and 20 of the Sooty Tern population were carried out between 1994 and 2015, and Myna depredation was monitored on 10 occasions between 2000 and 2008. Of all seabird eggs laid annually, we estimated that 19 % of them were depredated by c. 1000 Mynas. In declining severity of impacts of Mynas on all eggs lost, we estimated that 40 % was attributable to desertion, 39 % to puncturing eggs with no consumption and 21 % to puncturing and consumption. As far as we know, our study is the first to estimate the scale of seabird egg depredation by Mynas. Care is needed when applying our findings to other seabird populations. The scarcity of alternative food sources and the ease of locating high densities of Sooty Tern eggs on Ascension Island may have magnified the frequency of egg depredation by Mynas. That said, it is clear that Mynas are major egg predators and the severity of their impacts on native avian populations can be high. [ABSTRACT FROM AUTHOR]

Mercury (Hg) is a highly toxic metal that adversely impacts human and wildlife health. The amount of Hg released globally in the environment has increased steadily since the Industrial Revolution, resulting in growing contamination in biota. Seabirds have been extensively studied to monitor Hg contamination in the world's oceans. Multidecadal increases in seabird Hg contamination have been documented in polar, temperate and subtropical regions, whereas in tropical regions they are largely unknown. Since seabirds accumulate Hg mainly from their diet, their trophic ecology is fundamental in understanding their Hg exposure over time. Here, we used the sooty tern (Onychoprion fuscatus), the most abundant tropical seabird, as bioindicator of temporal variations in Hg transfer to marine predators in tropical ecosystems, in response to trophic changes and other potential drivers. Body feathers were sampled from 220 sooty terns, from museum specimens (n = 134) and free-living birds (n = 86) from Ascension Island, in the South Atlantic Ocean, over 145 years (1876–2021). Chemical analyses included (i) total- and methyl-Hg, and (ii) carbon (δ1³C) and nitrogen (δ15N) stable isotopes, as proxies of foraging habitat and trophic position, respectively, to investigate the relationship between trophic ecology and Hg contamination over time. Despite current regulations on its global emissions, mean Hg concentrations were 58.9% higher in the 2020s (2.0 μg g−1, n = 34) than in the 1920s (1.2 μg g−1, n = 107). Feather Hg concentrations were negatively and positively associated with δ1³C and δ15N values, respectively. The sharp decline of 2.9 ‰ in δ1³C values over time indicates ecosystem-wide changes (shifting primary productivity) in the tropical South Atlantic Ocean and can help explain the observed increase in terns' feather Hg concentrations. Overall, this study provides invaluable information on how ecosystem-wide changes can increase Hg contamination of tropical marine predators and reinforces the need for long-term regulations of harmful contaminants at the global scale. [Display omitted] • Sooty terns act as bioindicators of Hg temporal trends in the South Atlantic Ocean. • Feather Hg concentrations were 59% higher in the 2020s than in the 1920s. • Trophic position (δ1⁵N) and feeding habitat (δ1³C) influenced Hg long-term trend. • The influence of climate change and fisheries on Hg long-term trend are discussed. [ABSTRACT FROM AUTHOR]

The Tinhosas islands, in São Tomé e Príncipe, host the most important seabird breeding colony in the Gulf of Guinea, but information on its conservation status was hitherto unpublished or anecdotal, the last assessment having been performed in 1997. A two-day expedition to the Tinhosas islands was undertaken to estimate the status of breeding seabirds in 2013. Four of the five seabird species known to breed in São Tomé e Príncipe, namely Brown BoobySula leucogaster, Sooty TernOnychoprion fuscatus, Brown NoddyAnous stolidusand Black NoddyAnous minutus, occur on the Tinhosas. A decrease of 80% in Brown Booby numbers, possibly due to occasional exploitation, and a 30% increase in Sooty Tern and Black Noddy numbers, were found compared to 1997 data although survey methods differed. Breeding of Brown Noddy and Madeiran Storm-petrelHydrobates castroremains unconfirmed. Our estimates confirmed that BirdLife International Important Bird and Biodiversity Area criteria are met for at least one species, the Sooty Tern. The islands are not legally protected, nonetheless, apart from moderate levels of disturbance by fishermen who land on Tinhosa Grande, no alien species were seen, and no immediate threats to the Tinhosas colony were detected. Multiple visits within and between years are recommended, to census breeders, monitor threats and establish breeding phenologies. [ABSTRACT FROM AUTHOR]

Plastic is abundant in the oceans, reaching pelagic zones away from continents. Here we present the first recordings of plastic used as nest material in Sooty Tern nests, on a remote oceanic island. We describe our findings in terms of quantity, size and color of plastic debris. A total of 78 plastics were noted in 54 nests. Four color categories were found: Blue, White, Green and Red. Blue fragments were the most frequent color, present three times as much as white debris. This pattern was present despite blue fragments being smaller and lighter. The plastic debris of lowest frequency were the larger and heavier pieces (red). To our knowledge this is the first record of plastic in Sooty Tern nests. Trindade Island is on an oceanic zone expected to accumulate garbage due to the dynamic ocean currents. Such findings call for a closer inspection of pollution in the Atlantic Ocean. [ABSTRACT FROM AUTHOR]

Birds play a central role in the epidemiology of several flaviviruses of concern for public and veterinary health. Seabirds represent the most abundant and widespread avifauna in the western Indian Ocean and may play an important role as host reservoirs and spreaders of arthropod-borne pathogens such as flaviviruses. We report the results of a serological investigation based on blood samples collected from nine seabird species from seven islands in the Indian Ocean. Using a commercial competitive enzyme-linked immunosorbent assay directed against the prototypic West Nile flavivirus, antibodies against flaviviruses were detected in the serum of 47 of the 855 seabirds tested. They were detected in bird samples from three islands and from four bird species. Seroneutralization tests on adults and chicks suggested that great frigatebirds (Fregata minor) from Europa were infected by West Nile virus during their non-breeding period, and that Usutu virus probably circulated within bird colonies on Tromelin and on Juan de Nova. Real-time polymerase chain reactions performed on bird blood samples did not yield positive results precluding the genetic characterization of flavivirus using RNA sequencing. Our findings stress the need to further investigate flavivirus infections in arthropod vectors present in seabird colonies. [ABSTRACT FROM PUBLISHER]

The Cay Sal Bank in The Bahamas is one of the Caribbean region's most important areas for breeding seabirds, but the colonies previously lacked solid estimates. This paper describes results of four visits between 2010 and 2012. The Santaren Channel, used to transit to and from Cay Sal Bank, contained high numbers (6.1 ± 0.4 birds per km2) of seabirds. The Cay Say Bank has at least 117 detectable islands with 484 ha of land area; the most numerous colony was at Elbow Cay (23 ha). Audubon's Shearwaters ( Puffinus lherminieri) were breeding at 97 pairs per ha (total: 2,200; 95% CI = 1,650-2,800 pairs), Sooty Terns ( Onychoprion fuscatus) at 382 pairs per ha (total: 8,800; 95% CI = 6,900-10,700 pairs), Bridled Terns ( Onychoprion anaethetus) at 38 pairs per km coastline (5,829 m coastline; total: 220; 95% CI = 145-295 pairs) and Brown Noddies ( Anous stolidus) at 72 pairs per ha (total: 1,609; 95% CI = 1,070-2,250 pairs). The population of Audubon's Shearwaters is among the largest in the world while populations of the other species are regionally significant. Roughly 420 ha (87% of the available land) were visited; however, many of the smaller cays (43 islands with 30 ha of habitat) have still not been surveyed. Seabirds were present in low densities (0.3-20 total pairs per ha) on the other large islands, all of which contain populations of introduced black ( Rattus rattus) or Norway ( R. norveigicus) rats. These visits provide the first repeatable surveys of breeding seabirds at Cay Sal Bank. [ABSTRACT FROM AUTHOR]

On Bird Island, Seychelles, adult Sooty Terns are frequently found injured on the beach, usually with dislocated or broken wings, during the breeding season. By ruling out other possibilities we hypothesized that the injuries were caused by frigatebirds, and therefore predicted that (1) most attacks would take place in the late afternoon, when adult Sooty Terns normally return to the colony after feeding during the day; (2) most injuries would be inflicted during the late afternoon and so injured birds are most likely to be found on the beach the following morning, after they have swum ashore; and (3) frigatebird Fregata spp. attacks would be more frequent during chick rearing, when adults carry fish and/or squid for their chicks, than during incubation, when they carry only the food required for their own maintenance. At two-week intervals during the 2014 breeding season we undertook early morning and late evening 5-d surveys of the number of beached Sooty Terns, of frigatebirds chasing seabirds visible from the beach, and of frigatebirds in the communal roost. The first two predictions were supported by the data but the third was not; this failure was considered to be due to frigatebirds parasitizing other species, especially Lesser Noddies Anous tenuirostris, when these were more profitable sources of regurgitates. Overall, we conclude that frigatebirds are responsible for the injuries that cause Sooty Terns to be found on the beach, and that the number found on the beach is probably only a small proportion of the mortality inflicted on the Bird Island colony. [ABSTRACT FROM AUTHOR]

Over the last 12 years, the use of global positioning system (GPS) technology to track the movements of seabirds has revealed important information on their behaviour and ecology that has greatly aided in their conservation. To date, the main limiting factor in the tracking of seabirds has been the size of loggers, restricting their use to medium-sized or larger seabird species only. This study reports on the GPS tracking of a small seabird, the Sooty Tern Onychoprion fuscatus, from the globally important population breeding on Dog Island, Anguilla. The eight Sooty Terns tracked in this preliminary study foraged a mean maximum distance of 94 (SE 12) km from the breeding colony, with a mean trip duration of 12 h 35 min, and mean travel speed of 14.8 (SE 1.2) km/h. While our study was limited in scope, it showed that small loggers such as the ones used present new opportunities for accurately tracking the short-term movements of small seabird species, thus providing huge potential to advance our understanding of seabird behaviour and conservation. Indeed, all study birds foraged in waters outside of Anguilla's Exclusive Economic Zone near the neighbouring islands of Saint Martin, Saint Barthelemy, Saint Eustatius, and St Kitts and Nevis, with 50% of birds commuting along the same route, thus demonstrating that the conservation of this population, with further study, will have geopolitical complexities. [ABSTRACT FROM AUTHOR]

The article focuses on Anguilla which is a British Overseas Territory, considered an important bird area and known for its seabirds. Topics mentioned include the species that currently breed include Sooty Tern, Brown Booby, and Red-Billed Tropicbird, the Important Bird and Biodiversity Areas (IBAs) which holds seabird colonies, and the challenges on sustainable development to maintain the biodiversity and natural resources.

The article discusses the study that investigated egg adoption by Sooty Terns Onychoprion fuscatus, laying one egg and some found with two eggs in a nest. Findings discussed include probability of adoption dependent on the proximity of the new egg to the nest, unlikelihood of eggs placed further from nest being adopted and likelihood of its disappearance, probably due to predation, and second egg adoption appearing to result in prolonged incubation, compromising success of breeding attempt.

Breeding periodicity allows organisms to synchronise breeding attempts with the most favourable ecological conditions under which to raise offspring. For most animal species, ecological conditions vary seasonally and usually impose an annual breeding schedule on their populations; sub-annual breeding schedules will be rare. We use a 16-year dataset of breeding attempts by a tropical seabird, the sooty tern (Onychoprion fuscatus), on Ascension Island to provide new insights about this classical example of a population of sub-annually breeding birds that was first documented in studies 60 years previously on the same island. We confirm that the breeding interval of this population has remained consistently sub-annual. By ringing >17000 birds and re-capturing a large sample of them at equivalent breeding stages in subsequent seasons, we reveal for the first time that many individual birds also consistently breed sub-annually (i.e. that sub-annual breeding is an individual as well as a population breeding strategy). Ascension Island sooty terns appear to reduce their courtship phase markedly compared with conspecifics breeding elsewhere. Our results provide rare insights into the ecological and physiological drivers of breeding periodicity, indicating that reduction of the annual cycle to just two life-history stages, breeding and moult, is a viable life-history strategy and that moult may determine the minimum time between breeding attempts. [ABSTRACT FROM AUTHOR]

Abstract: The Mozambique Channel (western Indian Ocean) is a dynamic environment characterised by strong mesoscale features, which influence all biological components of the pelagic ecosystem. We investigated the distribution, abundance and feeding behaviour of seabirds in the Mozambique Channel in relation to physical and biological environmental variables, with a specific interest in mesoscale features. Seabird censuses were conducted in summer and winter during 7 cruises in the southern and northern Mozambique Channel. Tropical species accounted for 49% of the 37 species identified and 97% of the individuals, and species from the sub-Antarctic region constituted 30% of the identifications. The typically tropical sooty tern (Onychoprion fuscata) was the dominant species during all cruises, and overall accounted for 74% of the species observations and 85% of counted birds. Outputs of Generalised Linear Models at the scale of the Mozambique Channel suggested that higher densities of flying and feeding birds occurred in areas with lower sea surface temperatures and lower surface chlorophyll a concentrations. Most of the flocks of feeding birds did not associate with surface schools of fish or marine mammals, but when they did, these flocks were larger, especially when associated with tuna. While tropical species seemed to favour cyclonic eddies, frontal and divergence zones, non-tropical species were more frequently recorded over shelf waters. Sooty terns foraged preferentially in cyclonic eddies where zooplankton, micronekton and tuna schools were abundant. Among other major tropical species, frigatebirds (Fregata spp.) predominated in frontal zones between eddies, where tuna schools also frequently occurred and where geostrophic currents were the strongest. Red-footed boobies (Sula sula) concentrated in divergence zones characterised by low sea level anomalies, low geostrophic currents, and high zooplankton biomass close to the surface. Our results highlight the importance of mescoscale features in structuring the tropical seabird community in the Mozambique Channel, in addition to segregating tropical and non-tropical species. The mechanisms underlying the segregation of tropical seabirds seem to partially differ from that of other tropical regions, and this may be a consequence of the strong local mesoscale activity, affecting prey size and availability schemes. Beyond characterising the foraging habitats of the seabird community of the Mozambique Channel, this study highlights the importance of this region as a hot spot for seabirds; especially the southern part, where several endangered sub-Antarctic species over-winter. [Copyright &y& Elsevier]

Abstract: Using a combination of diverse large predatory fishes and one seabird, we collected information on the cephalopod fauna of the western Indian Ocean. We analyzed the stomach contents of 35 fishes representing ten families (Xiphiidae, Istiophoridae, Scombridae, Carangidae, Coryphaenidae, Alepisauridae, Dasyatidae, Carcharhinidae, Alopiidae and Sphyrnidae) and of the sooty tern Onychoprion fuscata of the Mozambique Channel from 2000 to 2010. Both fresh and accumulated beaks were used for identifying cephalopod prey. Cephalopods were important prey for twelve predators; swordfish Xiphias gladius had the highest cephalopod proportion; sooty tern (O. fuscata) and bigeye tuna (Thunnus obesus) had high proportions too. We recovered 23 cephalopod families and identified 38 species. Ten species from four Teuthida families (Ommastrephidae, Onychoteuthidae, Histioteuthidae and Ancistrocheiridae) and two Octopoda families (Argonautidae and Bolitaenidae) occurred very frequently in the stomach contents, while Sepiida were rare. Ommastrephidae were the most cephalopod food sources: the purpleback flying squid Sthenoteuthis oualaniensis was the most prevalent prey by far, Ornithoteuthis volatilis was important for eleven predators and few but large specimens of the neon flying squid Ommastrephes bartramii were recovered in the stomachs of swordfish in the Indian South Subtropical Gyre province only. Predators' groups were identified based on cephalopod prey composition, on depth in which they forage, and on prey size. Surface predators' diets were characterized by lower cephalopod diversity but greater average numbers of cephalopod prey, whereas the deep-dwelling predators (swordfish and bigeye tuna) preyed on larger specimens than surface predators (O. fuscata or yellowfin tunas Thunnus albacares). Our findings emphasized the usefulness of a community of marine predators to gain valuable information on the biology and the distribution of the cephalopod forage fauna that are discussed with regard to biogeographic province, marine predator, fishing gear to catch the large pelagic fishes, and size of the beaks recovered in the stomachs. [Copyright &y& Elsevier]

Resighting of adult Sooty Terns Onychoprion fuscatus that had been ringed on Bird Island, Seychelles, as chicks in 2002 indicated that birds of higher body mass at fledging had higher post-fledging survival than lighter birds. Resighting of birds that had been ringed at the same time, but at different developmental stages, suggested that birds that fledged from eggs laid late had lower post-fledging survival than chicks that fledged from eggs laid at the peak of the nesting season. These findings are discussed in relation to factors that influence chick survival within the colony and post-fledging survival in the marine environment, along with their implications for the commercial harvest of Sooty Tern eggs in Seychelles. [ABSTRACT FROM AUTHOR]

The article discusses the findings of a study to analyze how coastal waterbird communities responded to storm events that occurred in southern Louisiana in 2008. It notes that research was conducted for the breeding communities of various waterbirds in the Dernieres Barrier Island Refuge. The study reveals that abundant populations of species like the Brown Pelican and Royal Tern decreased from 2008 to 2010, while numbers increased for the Roseate Spoonbill and Sooty Tern from 2008 to 2009.

Abstract: We report for the first time levels of persistent organic pollutants in marine bird eggs from an oceanic island in the Indian Ocean, the world''s third largest ocean. Ten eggs each of the Common Noddy, also known as the Brown Noddy (Anous stolidus), and Sooty Tern (Sterna fuscata) were collected from Ile Cocos off the coast of the island of Rodrigues, located 560km east of the island of Mauritius. ΣPCBs had the highest levels (2.2 and 2.6ng/gwm, wet mass; 20 and 19ng/glm, lipid mass) for common Noddy and Sooty Tern, respectively (and following), then ΣDDT (1.9 and 3.1ng/gwm; 17 and 23ng/glm), and mirex (0.96 and 0.69 ng/g wm; 8.7 and 5.0ng/glm). ΣChlordanes (0.094 and 0.15ng/gwm; 0.48 and 0.73ng/glm) and Σtoxaphenes (0.26 and 0.61ng/gwm; 2.4 and 5.9ng/glm) are rare data for these compounds from this ocean. Brominated flame retardants were low (0.08 and 0.07ng/gwm; 0.7 and 0.7ng/glm). Multivariate analyses indicated different contamination patterns in the prey items as Sooty Terns had significantly higher levels of mean Σchlordanes and Σtoxaphenes, as well as CB105, -108 and -157. p,p′-DDE had an association with thinner eggshells in the Sooty Tern. Although the contaminant levels were in all respects low, industrialisation, development on the periphery, commercial exploitation of the marine environment, and pollutants transferred over long distances by marine debris is likely to add to chemical pressure in this region. Monitoring changes in background levels of pollutants in remote regions will indicate such trends, and marine bird eggs from Rodrigues would be an excellent site. [Copyright &y& Elsevier]

The article discusses long-term trends in the timing of breeding of both the Bridled Tern Onychoprion anaethetus and Brown Noddy Anous stolidus in relation to the El Nino Southern Oscillation. It also explores the foraging ecology of the two species off southwestern Australia and explains the role that differences in foraging ecology between the two species may have in considering contrasting population responses to a shifting ocean climate. It predicts that species-specific responses to changes in ocean climate will lead to a significant drop in Bown Noddy, and perhaps Lesser Noddy and Sooty Tern populations, in the region.

The article presents a study on the first attempted breeding and pre-breeding survival in Seychelles Sooty Terns Onychoprion fuscatus. The researchers used a capture-mark-recapture model to estimate adult and pre-breeder survival and the probability of recapture and age-specific probabilities of first-time attempted breeding. They also estimated annual adult survival as 0.913 and annual pre-breeder survival at 0.767. They found that the low return of chicks in 1997 suggests either high emigration or lower survival of birds.

The article presents a study on the foraging ecology of three dark tern species breeding in southwestern Australia using nitrogen and carbon stable isotope analysis. The researchers extracted the sixth primary feather from adults to identify their stable isotope values from foraging during the nonbreeding period and collected samples from Bridled Terns from a colony on Penguin Island. They also compiled samples of Anchovy Engraulis australis and Beaked Salmon Gonorhynchus greyi from several intact individuals sorted from various regurgitated boluses.

The article discusses a study on niche partitioning among and within sympatric tropical seabirds found at the Palmyra Atoll National Wildlife Refuge in the Pacific Ocean. The difficulty of conducting resource partitioning among predators may be attributed to the low productivity and unpredictable nature of tropical water resources. There were 10 breeding species that formed part of the seabird community at Palmyra including the brown noddies Anous stolidus, the white terns Gygis fuscata, and the sooty terns Sterna fuscata.

The article discusses a study which investigated the association between the nesting behavior of the Dry Tortugas (DRTO) Sooty Terns and vegetation and bare ground cover and its effect on the incidence of egg predation. The study was conducted on Bush Key in Dry Tortugas National Park in Florida. A Bayesian modeling framework was developed by the researchers and hypothesized a shift in the nesting behavior of DRTO Sooty Terns.

Tropical island species and ecosystems are threatened worldwide as a result of increasing human pressure. Yet some of these islands also lend themselves to restoration, as they are physically defined units that can be given focused attention, as long as resources are available and clear conservation targets are set. Cousine Island, Seychelles, is a tropical island that has received such intensive restoration. From a highly degraded island in the 1960s, the island has now been restored to what is believed to be a semblance of the natural state. All alien vertebrates have been eradicated, as have 25 invasive alien plants. Cultivated plants are now confined to one small section of the island. Poaching of nesting marine turtles has been stopped, leading to an increase in turtle breeding numbers. The shearwater population has increased in size with poaching activities under control. The Sooty tern has also returned to the island to breed. The coastal plain has been restored with over 2,500 indigenous shrubs and trees, which have now grown into a forest carpet. There are strict quarantine procedures on the island, keeping it free of rats, mice, various alien invertebrates and potentially invasive alien plants. Three threatened Seychelles endemic land birds (Seychelles warbler, Seychelles magpie robin and Seychelles white-eye) have been introduced and are thriving, with these introductions contributing to both the magpie robin and the white-eye being downgraded from CR to EN (the warbler remains at VU). Ecotourism, and nature conservation for the local inhabitants, have been introduced in a way that does not reduce the improved compositional, structural and functional biodiversity of the island. The result of the restoration effort appears to be sustainable in the long term, although challenges still remain, especially with regards to adequate clean water and a non-polluting power supply on the island. Cousine is thus paving the way in the art and science of tropical island restoration as a legacy for future generations. [ABSTRACT FROM AUTHOR]

The article discusses findings of research on two major seabird colonies in Madagascar. The Sooty Tern Onychoprion fuscata colony is found at Nosy Manampaho, while the Crested Terns Thalasseus bergii colony is located at Nosy Foty. Funded by the French Institute for Biodiversity, the researchers had visited several islets in the north of Antsiranana Province in Madagascar in July 2008 to conduct field work. The activities done by the researchers included the census of breeding seabirds, determination of the conventional uses of seabirds by coastal villagers and the assessment of the conservation status of the colonies. Other species of seabirds that were found in Madagascar included the Caspian Tern Hydroprogne caspia and Roseate Tern Sterna dougallii.

Intense El Niño events severely impact seabird populations, often months in advance of peak temperature anomalies. The trophic mechanisms responsible for these impacts are unknown but are assumed to operate at seasonal scales and to be linked to ocean productivity changes. Precursors to El Niño events include changes in both sea-surface temperature and the depth of the 20°C thermocline. Foraging piscivorous seabirds are known to be sensitive to both thermocline depth and sea-surface temperature change, but the potential influence of these phenomena on breeding dynamics is unknown. Using 18 years of data on three seabirds of the western tropical Pacific, we show that pelagic seabird breeding participation is directly and independently related to changes in both surface chlorophyll concentration and thermocline depth that occur well in advance of El Niño generated sea-surface temperature anomalies. In contrast, breeding in an inshore foraging species is not correlated with any environmental/biological parameters investigated. These findings demonstrate that El Niño related phenomena do not affect seabird prey dynamics solely via productivity shifts at seasonal scales, nor in similar ways across different seabird foraging guilds. Our results also suggest that population declines observed in the western tropical Pacific may be directly related to the frequency and intensity of El Niño anomalies over the study period. [ABSTRACT FROM AUTHOR]

A personal narrative is presented which explores the author's experience of observing the first occurrence of Sooty Tern in Colorado.