Search

Understanding sex differences in foraging behaviour has important implications for breeding biology and population ecology. This requires the evaluation of segregation throughout the annual cycle, including the non-breeding period. We studied the diet and foraging strategies of the Common Tern (Sterna hirundo) at an intraspecific level by sampling birds during two consecutive non-breeding periods in Punta Rasa, Buenos Aires Province, Argentina. Blood samples were taken for sex determination and carbon and nitrogen stable isotope analysis. No isotopic difference was observed between years, but higher isotopic values occurred during late non-breeding period. Carbon and nitrogen isotopic values were similar between sexes; however, differences were observed in standard ellipse analyses, considered to represent isotopic niches. Even though the Bayesian ellipse areas overlapped, females showed wider isotopic niches throughout the non-breeding period. This could be related to different feeding strategies, foraging areas or migratory stopover sites at either intraspecific or individual levels. Diet contributions of different prey categories estimated through mixing model analyses suggested a higher contribution of estuarine fish than of marine pelagic species. These results highlight the importance of stable isotope analyses as a complementary methodology to traditional diet studies, particularly during the non-breeding period. Fil: Lamacchia, Paola. Universidad Nacional de Mar del Plata. Facultad de Cs.exactas y Naturales. Departamento de Biología. Laboratorio de Vertebrados; Argentina Fil: Madrid, Enrique Alberto. Universidad Nacional de Mar del Plata. Facultad de Cs.exactas y Naturales. Departamento de Biología. Laboratorio de Vertebrados; Argentina Fil: Mariano y Jelicich, Rocío. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina

We have investigated characteristics of colony site of three sympatric breeding tern species on small islands of a subtropical region, the Persian Gulf. The three most populous ground-nesting waterbird species – Bridled Tern Onychoprion anaethetus, Lesser Thalasseus bengalensis and Greater Thalasseus bergii Crested Terns – were studied during the 2009–2011 breeding seasons. The average area size of mixed colonies was 454 m2. The density of nests of the Bridled Tern was 846 nests/ha. The proportion of the number of nests in a mixed colony for Lesser Crested Tern (5546 nests) was approximately 10-fold compared to the Greater Crested Tern (542 nests). The density of Bridled Tern nests/ha was significantly higher in areas with 50–75% vegetation cover (>1200 nests/ha) than in areas of

Based on information obtained from publications, online material and experienced birdwatchers we describe changes in the breeding avifauna of Israel between 2003 and 2016. We provide details on nine species that were found breeding in Israel during this period for the first time (Common Shelduck, Great Cormorant, Black-winged Kite, Caspian Tern, White-cheeked Tern, Common Wood Pigeon, Black Bush Robin, Basra Reed Warbler, Chiffchaff); two species that were found breeding in Israel after they were not documented breeding for more than 50 years (Great Crested Grebe, Pallid Scops Owl), one species that significantly extended its breeding range in Israel (Striated Heron), and two exotic species that have recently established populations in Israel (Monk Parakeet, Vinous-breasted Starling). This brings the number of bird species breeding in Israel in 2016 to 220. We also report here that out of six new breeding species reported in 2003, three species established breeding populations in Israel, while the other s...

Capsule In the Whiskered Tern Chlidonias hybrida, hatching success was similar at nests where both parents were caught during the same trapping session and nests where parents were caught on different days. Trapping both mates during the same session may represent an efficient approach to reduce fieldwork effort, but it should be preceded by a pilot study, confirming that it does not affect breeding success.

The analysis of mitochondrial DNA (mtDNA) base composition, codon usage, and genome arrangement patterns can provide insight into metabolic pathways and evolutionary history. Here, we report on the...

Five to seven subspecies of Antarctic Tern (Sterna vittata) are recognised, with at least three (S. v. vittata, S. v. tristanensis and S. v. sanctipauli) wintering in South Africa. Morphological characters used to define these subspecies are not perfectly reliable, but fidelity to nesting site suggests they could be genetically distinct. We used morphological data and DNA to investigate the validity of subspecies. We further used stable isotope analysis of feather samples collected from the non-breeding grounds in South Africa to attempt to ascertain the population of origin. Nuclear and mitochondrial DNA sequence data identified two major genetic clades: one mostly comprised individuals partially or completely matching the morphological description of S. v. tristanensis, the other included individuals from S. v. vittata and S. v. sanctipauli. Stable isotope values indicated that juveniles originated from at least three populations. Irrespective of their morphological and genetic characteristics, most immatures moulted in Antarctic waters, and adults moulted in various habitats. Their colony of origin could not therefore be inferred from stable isotope values from feathers. Results indicate that morphological groupings may reflect a north–south cline across the Indian Ocean. Adequate conservation strategies require rigorous reassessment of the currently accepted subspecies, including DNA analyses of samples from the breeding grounds, particularly on Amsterdam and St Paul Islands.

When fitness return differs for sons and daughters, parents are selected to adjust brood sex ratio to maximise the reproductive value of their offspring. The aim of this study was to investigate seasonal adjustments in brood sex ratio of a sexually dimorphic colonial larid, the whiskered tern Chlidonias hybrida. I found a significant seasonal change in brood sex ratio from sons to daughters in the studied whiskered tern population. This pattern was consistent with a seasonal decline in the early-life physiological condition of both male and female whiskered tern hatchlings measured with blood concentrations of haemoglobin. The incapability of late breeders to raise male offspring of high quality indicates that they should adaptively adjust brood sex ratio towards daughters, which are more likely to reproduce regardless of their phenotypic and genetic quality. Thus, I suggest that the seasonal change in brood sex ratio from sons to daughters in the whiskered tern may be attributed to the declining quality ...

The nesting success and nestling growth were studied in a Gull-billed Tern Gelochelidon nilotica Gmelin, 1789 colony located in western Iran, during the 2008 breeding season. The nesting success was modelled in order to assess the effects of various nest-site parameters and nest initiation date. Nestling growth rate, described as body mass, head-bill and tarsus growth per day during the first 10 days of age, was analyzed in relation to brood size and the hatching position of nestlings. Mean daily growth rate of nestlings’ mass (7.82 ± 0.35 g/day) varied in broods of different size but remained independent of nestlings’ hatch order within the brood. Similarly, the growth rate of head-bill length was influenced only by brood size while neither brood size nor hatching position had a significant effect on the wing length growth rate. Nest initiation dates and plant cover around the nests were the most important factors predicting nesting success. As time of breeding period progressed, the rate of nesting success increased. Higher plant cover around the nest also increased the nesting success, probably by hiding the eggs and providing shelter for nestlings thus decreasing predation and mortality rate.

Capsule Patterns of parentage were studied in a colony of Whiskered Terns Chlidonias hybrida in central Poland. We assessed the parentage of 64 chicks from 30 broods using five polymorphic microsatellite loci. The rate of extra-pair paternity was estimated at 8.1% of offspring and 11.8% of broods (the upper 95% CL: 16.9% and 27.1%, respectively), whereas intraspecific brood parasitism was recorded in 4.7% of offspring and 10.0% of broods (the upper 95% cl: 9.9% and 20.7%, respectively). The data obtained on the occurrence of alternative reproductive strategies in Whiskered Tern are consistent with general patterns of parentage found in other colonial larids.

Mesozoic non-avian theropod dinosaurs displayed a diverse range of egg types and clutch forms, suggesting a variety of nesting behaviours, some of which may be shared with birds. More accurate infe...

Capsule The first confirmed record of breeding by a one-year-old Common Tern Sterna hirundo is revealed by ringing evidence, despite second-summer plumage characteristics.

Capsule Body mass of Whiskered Tern chicks from the central parts of subcolonies grew at a higher rate in comparison to chicks hatched in the peripheral zones. Growth rates of both body mass and head length correlated positively with nest density. We suggest that spatial distribution of pair quality within the colony of Whiskered Terns follows a central–periphery gradient.

The Argentine Anchovy (Engraulis anchoita) is one of the most important pelagic fishery resources of the Patagonian Shelf and is known to be an important prey item for several seabirds of the northern Argentine coast. The South American Tern (Sterna hirundinacea) is endemic to the Atlantic and Pacific coasts of South America and, on the Atlantic coast, breeds from central Brazil to southern Argentina. Large non-breeding flocks form during the austral winter and spring from southern Brazil to northern Patagonia. The diet of the South American Tern was studied over three consecutive non-breeding seasons through the analysis of regurgitated pellets. The Argentine Anchovy comprised >80% (index of relative importance) of fish prey in the diet, and remained important throughout the study period. Other important fish prey were Cornalito Silverside (Odonthestes incisa), Pejerrey Silverside (O. argentinensis) and Stripped Weakfish (Cynoscion guatucupa). The growing interest in commercially fishing Argentine Anchovies makes it important that studies are conducted to determine the potential effect of the harvest of Anchovies on South American Terns and other top predators.

This paper reports on the Teacher Education Research Network (TERN) initiative, which piloted a model for research capacity building in teacher education in the North West of England with the aim of providing early and mid career researchers from seven regional universities with opportunities for professional learning and development. It explores the intricate dynamics of the learning journeys undertaken by the participants and critically examines the structural, social and cultural factors involved in the navigation of the complex ecologies in which they were embedded as teacher educators and how this impacted on their learning. It concludes that initiatives such as TERN can result in academic learning and professional development, but in view of the internal and external pressures confronting education departments today it also raises pertinent issues with regard to the sustainability of such projects. As such the paper makes a strong contribution to the growing international literature on academic lear...

We analysed mercury levels in the breast feathers of several breeding seabirds – White-tailed Tropicbird (Phaethon lepturus), Audubon’s Shearwater (Puffinus lherminieri), Lesser Noddy (Anous tenuirostris), White Tern (Gygis alba), Sooty Tern (Onychoprion fuscata) and Roseate Tern (Sterna dougallii) – on Aride Island in the Seychelles during three periods between 1996 and 2005. Mercury concentrations tended to be higher in the second sampling period (2002–03) than the first (1996–97), particularly for inshore-feeding species. El Nino events in 1997–99 and 2002–03 might help to explain this pattern, through an increase in mercury bioavailability for seabirds that forage inshore. However, levels of mercury in tissue decreased significantly from the first period (1996–97) to the third period (2004–05) for inshore-foraging species (Lesser Noddy mean ± s.e.: 0.82 ± 0.02 μg g–1 v. 0.53 ± 0.06 μg g–1 respectively) and more wide-ranging, offshore-feeding species (Sooty Tern: 1.16 ± 0.05 v. 0.59 ± 0.04; White-tailed Tropicbird: 1.82 ± 0.05 v. 1.43 ± 0.09). Wide-ranging species of seabirds are more likely to be useful bioindicators at large spatial scales, with such species suggesting a decreasing trend in mercury pollution in the western Indian Ocean.

This article offers an initial account of the Teacher Education Research Network (TERN), a pilot education research capacity building project funded by the ESRC and designed to test a ‘social practices’ model for building an educational research infrastructure across England. The TERN project is still running at the time of writing, so it is not yet possible to offer a full evaluation or a theorised analysis of the project. Setting the initiative within the regional context of teacher education in the North West of England, the article describes elements of the project and begins to explore their significance, drawing on early evaluation data. The article adapts Charles Desforges’ equation of research capacity building as ‘Capacity = expertise × motivation × opportunities’ as a frame for this exploration.

Cayenne (Thalasseus sandvicensis eurygnathus) and Royal Terns (Thalasseus maximus) breed in mixed colonies in Argentina. This paper presents the first detailed information on their breeding diet and assesses differences and overlap between species in the type and size of prey. During 2004 and 2005, observations of prey delivered to mates and chicks were carried out at Punta Leon, Patagonia. The diet of Cayenne and Royal Terns comprised nine and 10 prey species respectively. Fish comprised >99% of the prey of both species of tern in the two study years. Both species had a fairly specialised diet based on pelagic schooling fish, mostly Argentine Anchovy (Engraulis anchoita) and two species of silversides (Odontesthes spp.). Despite observed overlap in trophic resources, our results showed that Argentine Anchovy was the main prey for Royal Terns, whereas the two species of silversides together with Anchovy comprised the bulk of the diet for Cayenne Terns. Fish delivered by Cayenne Terns were significantly smaller than those by Royal Terns. Results suggested that both type and size of prey may be important factors permitting food partitioning between the two species of tern during the breeding season.

Two subspecies of the Gull-billed Tern (Sterna nilotica) occur along the coasts of north-western Australia: the large, pale Australian subspecies macrotarsa, and a smaller, darker migratory subspecies from northern Asia. On the basis of banding data we describe the measurements and moult strategies of both subspecies in north-western Australia and identify the Asian migrants as subspecies affinis. Asian migrants have a predictable plumage cycle including regular alternation between breeding and non-breeding plumage in adults. The moult strategy of Australian macrotarsa is more varied and we argue it is adapted to exploit unpredictable breeding opportunities. Plumage and structural characters described in this paper allow the two subspecies to be distinguished in the field, and field observations demonstrate some broad ecological differences between them. Adult affinis occur in Australia from August to April, with smaller numbers of immatures remaining during the dry season; they are strictly coastal, occurring in highest abundance over intertidal flats near mangrove systems where they pluck prey from the surface of mud while in flight. Subspecies macrotarsa uses the north-western Australian coast as a non-breeding area, but it does so mainly during the dry season and also uses grasslands and inland wetlands; unlike affinis, in Roebuck Bay it is regularly kleptoparasitic, stealing large crabs (Macropthalmus sp.) from Whimbrels (Numenius phaeopus).

Black-fronted Terns (Sterna albostriata) are an endangered species endemic to New Zealand whose breeding biology and survival are poorly understood, yet the species is in urgent need of management. I studied aspects of Black-fronted Tern breeding ecology and survival on the Ohau River, South Island, New Zealand, from 1998 to 2001. Over three breeding seasons, 50.2% of 1022 nests successfully hatched one or more eggs. Predation (24.6%) and desertion (21.4%) were the main causes of nest failure. At least 28% of all hatched chicks (n = 897) survived to fledge. Productivity for each of three breeding seasons was estimated at 0.23, 0.34 and 0.27 fledglings per nest. Hatching and fledging rates at individual colonies ranged widely, largely because of the impacts of predation by introduced mammals. Evidence from video cameras placed at nests suggested predators were a cause of nocturnal and permanent desertion of both eggs and chicks, and that single predators could destroy entire colonies. Based on re-sightings of 72 colour-banded adult Terns, adult annual survival rate was estimated at 0.88–0.92 but the associated confidence intervals were wide (0.57–0.99). Most re-sightings (77%) of banded adults that were nesting were either in the colony in which they were banded or elsewhere on the Ohau River. This is the first comprehensive study on the breeding biology of Black-fronted Terns and indicates that predator control is essential to the future survival of the species.

Synopsis Previous research has indicated that the presence of harvesting residues, post-planting tern perature and rainfall, and insect pests and diseases, are among the main causes of mortality during re-establishment of Pinus patula stands. The main objectives of this work were to confirm previous observations on the effects of these factors on initial survival and growth of P. patula seedlings. Three harvest residue management treatments (burning, harvesting residues left in situ or removed) and four pest management treatments applied at planting (fungicide, insecticide, fungicide and insecticide, and a control, where no pesticides were used) were tested in combination with each other. For the first two years after planting, there was a significant effect of harvest residue and pest management on survival. At two years, survival in the burned treatment was 59 %, possibly due to the presence of Rhizina undulata. Where the harvest residues were not burned, the survival was 88 %. Application of a fungicid...

The incidence of extra‐pair paternity and egg dumping was investigated in a colony of common terns (Sterna hirundo), a colonial seabird, in the Venetian lagoon. Ten families were sampled and multilocus DNA fingerprinting analysis was performed. No indication of extra‐pair paternity or egg dumping was found in any of the families. The results are discussed in the light of life‐history strategies, the benefits of coloniality and the evolution of adoption behaviour in the species.

This study employed a means of indexing the abundance of Zachvatkinia caspica (Mironov, 1989), an analgoid feather mite, among the primary feathers of its host, the Caspian Tern (Sterna caspia Pallas, 1770) in a manner that allowed for quantification of overall mite densities as well as spatial distributions of mites throughout the feathers. These mite-density estimates were used to examine properties of the hosts that may influence mite distributions both among different birds and within individual wings. Mite densities correlated negatively with host size and body condition (as indicated by fat reserves). Additionally mite loads on male birds were approximately 30% greater than those on female birds. Regarding within-host (or within-wing) mite distributions, mite densities were greatest among the outer five primaries and on the outer half of each feather, which contradicts predictions of spatial distributions based on aerodynamic considerations but roughly corresponds with areas of greatest bar...

The distribution, abundance and biomass of seabirds in Western Port, Victoria, were surveyed between April 1991 and August 1994. Individuals were counted along an 81-km series of transects from a boat at approximately monthly intervals. A total of 25 seabird taxa were recorded, of which 18 and 15 were common to those recorded by an earlier study in Port Phillip Bay and waters south of Phillip Island, respectively. The most numerous species by far was the Short-tailed Shearwater (Puffinus tenuirostris) followed by the Silver Gull (Larus novaehollandiae), Little Penguin (Eudyptula minor) and Crested Tern (Sterna bergii). Distribution within Western Port was not uniform, with pursuit divers such as cormorant and grebe species being recorded mostly in the shallow Eastern Arm. In contrast, surface-seizing (e.g. albatrosses), surface-plunging (e.g. Crested Terns), shallow-plunging (Australasian Gannet, Morus serrator) and pursuit-plunging (e.g. shearwaters) species predominated in the deeper Western Arm of Western Port. These species were also seasonally abundant, with peak numbers for most occurring in late summer–early autumn, which coincides with the reported influx of juvenile clupeoid fish into Western Port. Average biomass (686 ± 395 kg) comprised mostly Short-tailed Shearwaters, Little Penguins and Pied Cormorants (Phalacrocorax varius). Biomass density (8.5 kg km–2) was similar to that reported for Port Phillip Bay (8.1 kg km–2) but lower than off the southern coast of Phillip Island (9.9 kg km–2).

Population collapse of common tern (Sterna hirundo) from Lime Island in the St. Mary's River, Michigan, USA were related to the 2,3,7,8-chlorine substituted dioxins, furans, dioxin-like PCBs, and other possible factors using unhatch egg target contaminant analysis. The most toxic congeners, 2,3,7,8-TCDD/DF was found in all samples at noticeable concentrations. Magnitude of sum 2,3,7,8-PCDD/DFs were within the range of 39–93 pg/g wet wt. Dioxin-like PCBs were within the range of 360–1230 ng/g wet wt. Great Toxic Equivalent Quantity (TEQ) contributions by 2,3,7,8-TCDF, 2,3,4,7,8-PeCDF, 2,3,7,8-TCDD, 1,2,3,7,8-PeCDD, and dioxin-like PCBs such as CB-77, CB-126 and CB-105 are considered greatly due to their influence of poor embryo development and consequent damage of embryos of common terns in egg injection studies. However, other organochlorines, heavy metals, and/or synergistic effects also taken in to account. On the whole, TEQs in the tern eggs were greater than the Lowest-Observable-Adverse Effect Level ...

Human disturbance to nesting colonial birds has increased with the massive development of coastal regions and rapid improvement in technology of watercraft. Disturbance to nesting common terns (Sterna hirundo) by boats was examined over a five-year period, with different degrees of management of personal watercraft (PWC) activities. In the five years before this study, reproductive success had declined to zero, perhaps due to excessive personal watercraft activity. Terns responded with significantly more upflights to PWCs that raced by and circled the island, than to motor boats that travelled slowly and remained in the channel. Public meetings and an educational campaign were successful in decreasing the percent of PWCs that raced and ran around die island, which in turn decreased die number of tern upflights and increased reproductive success. Without continued public meetings and education, PWCs began to race around the island, and the terns responded by moving from island edges to central are...

The diet of juvenile Crested Terns (Sterna bergii) at Phillip Island, Victoria was examined throughout two breeding periods, 1999–2000 and 2000–01. Nine species of fish and two species of squid were identified in the chick regurgitations, with significant differences among sampling days and between seasons. Anchovy (Engraulis australis) and Jack Mackerel (Trachurus declivis) were the two most abundant prey in both seasons, making up 63% and 21% of the diet, respectively, followed by Barracouta (Thyrsites atun, 4%) and other fish (12%). Anchovy was also the main prey for Little Penguins (Eudyptula minor) in 2000–01. In addition, years of low numbers of breeding Crested Terns coincided with years of low breeding success of Little Penguins over seven breeding seasons at Phillip Island. It seems that the breeding performance of both terns and penguins may be affected by the same variation of food supply. We also estimated roughly that this tern population consumes 28.7 tonnes of fish per breeding period based on the daily energy expenditure of seabirds. This consumption is about 10% of the commercial catches of Anchovy and Jack Mackerel in 2000–01, highlighting the importance of terns as natural consumers in the local ecosystem during the breeding period.

The nominate race of the Crested Tern, Sterna bergii bergii, first breeds when aged three years, but may not be fully recruited to breeding colonies until six years old because many birds do not breed in years of food scarcity. A 21-year-old bird breeding at Dassen Island was the oldest record for the species. There are 109 records in South Africa of birds alive when aged 15 years or older. Of birds whose colony of origin was known, 18% of those breeding and 27% of those present at colonies were at their natal localities. Most cohorts bred at several localities and breeding at most colonies was by birds fledged at several localities. Crested Terns in the Western Cape mainly breed between January and June. Most eggs are laid between January and April. Mean clutch size is 1.02 eggs. At Robben Island in 1987 and 1988 the average number of chicks fledged per breeding pair was estimated to be between 0.48 and 0.59.

Capsule Colonies were larger and breeding success lower in mink-inhabited areas. Aims To examine the impact of mink on dense aggregations of ground-breeding seabirds on islands previously isolated from mammalian predators. Methods We compare 1990–93 tern breeding data with records before and after mink arrival. Results In the early 1990s, terns showed no preference for mink-free islands. The breeding behaviour and success of tern colonies in mink-inhabited areas did not significantly differ from that in mink-free areas. However, colonies were larger and breeding success lower in mink-inhabited areas compared to mink-free areas, trends which might reflect longer term mink impact. Conclusions As mink spread south there seems to be a gradual increase in tern colony size affecting Lewis, then Harris and, recently, the Sound of Harris.

Much effort in life-history theory has been addressed to the dependence of life-history traits on age, especially the phenomenon of senescence and its evolution. Although senescent declines in survival are well documented in humans and in domestic and laboratory animals, evidence for their occurrence and importance in wild animal species remains limited and equivocal. Several recent papers have suggested that methodological issues may contribute to this problem, and have encouraged investigators to improve sampling designs and to analyse their data using recently developed approaches to modelling of capture-mark-recapture data. Here we report on a three-year, two-site, mark-recapture study of known-aged common terns (Sterna hirundo) in the north-eastern USA. The study was nested within a long-term ecological study in which large numbers of chicks had been banded in each year for > 25 years. We used a range of models to test the hypothesis of an influence of age on survival probability. We also tested for ...

Small seabirds are very sensitive to changes in the availability of prey and thus may be good indicators of changes in species composition and availability of prey. However, long-term data on dietary variation is scarce for tropical tern species. This paper assembles 9 years of data on deliveries of fish prey to Roseate Tern chicks of known-age on Aride Island, the Seychelles, in the western Indian Ocean, to examine: (1) the role of intrinsic (age of chicks) and extrinsic (local oceanographic conditions) factors on chick food provisioning, and (2) the temporal variation in intake rate of chicks. Our results show low annual variability in dietary composition: 75-97% of all ingested items were goatfish (Mullidae), which agrees with previous studies showing that these form the main prey fish for the Seychelles seabird community. Intake rate ofchicksvariedconsiderablyamongyears,from0.86 g fishingestedchick -1 h -1 in1997to3.12 gchick -1 h -1 in2005,with pooryearsshowingamuchhighercoefficientofvariationthangoodyears.Intakerateofchickswassignificantlycorrelated with local chlorophyll-a concentration and sea-surface temperature of the preceding 2 weeks. This suggests that food provisioning of tropical Roseate Tern chicks is sensitive to fluctuations in local oceanographic conditions that affect the availability of prey fish at a short temporal scale, and that Roseate Terns are suitable sentinel organisms to indicate local changes in environmental conditions.

This paper reports my observations during 1994–97 for both American Samoa and [W] Samoa. New waders added to the Samoan list are Wood Sandpiper (Tringa hypoleucos), Red-necked Stint (Calidris ruficollis), and Red Knot (Calidris canutus). The new breeding records are for the Black-naped tern (Sterna sumatrana), Bridled Tern (Sterna anaethetus), the Common Noddy (Anous stolidus), Crimson-crowned Fruit Dove (Ptilinopus porphyraceus) and the Red-headed Parrot-finch (Erythura cyaneovirens), in Samoa. Crested terns (Sterna bergii), Brown Boobies (Sula leucogaster) and Fairy Terns (Sterna nereis) were also observed with juveniles and so must be regarded as possible breeders in one of the Samoas.

Behaviour of birds and radiotracking indicated that Cory's Shearwaters join rafts closest to the location of their nest site. Rafting numbers of Cory's Shearwaters per kilometre of coast were higher around Corvo than around other islands in the Azores archipelago. Densities were most closely correlated with the surface area of cliff in each coastal sector, both comparing between islands and across all coastal sectors in the archipelago. After accounting for effects of cliff area, residual densities of Cory's Shearwaters were weakly positively correlated with the presence of tern colonies in one analysis and negatively correlated with the presence of urban areas in another. However, there were no correlations with the presence of other breeding procellariiforms, which tended to occur only on small rat-free islets. In contrast to the situation in other parts of its range, in the Azores, Cory's Shearwaters appear to nest predominantly on large cliffs, which are free from human exploitation and may be relativ...

The research was carried out on the Didžioji Island, Lake Kretuonas, Aukstaitija National Park. The results obtained showed no remarkable differences between the centre and the periphery of the colony concerning predation on Common Terns (Sterna hirundo). Just embryo mortality (number of not hatched out eggs) was reliably higher in the periphery than in the centre. The most successful hatching of chicks and their survival within the first days after hatching were recorded for the tern nests with the eggs laid during the mass egg-laying season. In synchronous and asynchronous three-chick broods, survival of nestlings varied. In asynchronous broods, the last chicks grew slower due to sibling competition, percentage of their mortality being highest of all. In two- and three-chick broods, feeding intensity of each chick was, in general, similar and depended just on individual features of a certain pair and the abundance of food resources. It was due to a louder vocal stimulation that adults brought up food to...

Large numbers of seabirds have been ringed in Britain and Ireland by volunteers and, to a lesser extent, professional ornithologists. At present, the species with about 5,000 or more ringed per year are Guillemot, Storm Petrel, Herring Gull, Puffin, Arctic Tern and Lesser Black‐backed Gull. Storm Petrel, Cormorant, Shag, Herring and Lesser Black‐backed Gulls and Guillemot provide in excess of 200 recoveries per annum per species. The wintering grounds and general migration routes of most British and Irish seabirds are known but most analyses are rather dated. This might hinder the prediction of effects of threats to British and Irish Seabirds arising away from colonies. Recoveries have proved extremely useful in highlighting seabird conservation issues, such as the killing of terns in West Africa and the drowning of auks in fishing nets. The finding of long‐term population studies of colour‐ringed seabirds is under threat. In future we may have to rely more on analyses of metal ring recoveries for obtaini...

Isomer‐specific concentrations of polychlorinated biphenyls (PCBs) including highly toxic non‐, mono‐ and di‐ortho coplanar congeners were determined in resident, migratory birds and bat collected from south India. Among 11 different species, total PCB concentrations were in the range of 80–2000 ng/g (wet wt) in birds and 190–330 ng/g (wet wt) in bat. IUPAC 105, 118, 126, 138, 153 and 180 were the predominant congeners in birds and bat. Concentrations of three non‐ortho coplanar PCBs such as 3,3’, 4,4'‐T4CB, 3,3’, 4,4’, 5‐P5CB, and 3,3’, 4,4’, 5,5'‐H6CB were 2–3 orders of magnitude less than those of total PCBs. Toxic equivalencies (TEQs) were estimated based on Toxic Equivalent Factors (TEFs) proposed by Ahlborg et al. (Chemosphere, 28, 1049–1067, 1994). TEQs of non‐ and mono‐ortho PCB congeners in various birds were in ihe range of 10–50 pg/g (wet wt), in which Short‐billed Mongolian Plover contained the lowest and White‐cheeked Tern had the highest. In most of the species, non‐ortho congeners contribut...

Summary: We report numbers and distributions of the breeding seabird community of the Gambier Islands (Eastern Polynesia, South Pacific Ocean), obtained in 1995 and 1996. Comparing these data with those collected in 1922, 1965‐69 and 1971, we assess the extent of changes in distribution and numbers of seabirds. None of the 14 species recorded previously to 1995‐96 has disappeared, but numbers and ranges of all the tern species have decreased. Breeding of three additional species ( Pterodroma spp.) has been discovered or confirmed in 1995‐96, though their numbers are very small. We also identified an unknown Cookilaria petrel, of which a wing was collected in 1922 on Mangareva, but which was not recorded later. Although seabird diversity on Gambier Islands is high, no species breeds in large numbers. Indeed, several species have tiny population sizes, and concern is therefore expressed for the future of this seabird community. Data on seabirds in Eastern Polynesia are scanty, owing to the difficulties of reaching the 141 main island groups, which are spread over more than 4 000 000 km2. Moreover, no breeding site has been monitored regularly during the 20th century. Information related to seabirds comes from a few expeditions mostly led by natural history museums (see Holyoak & Thibault 1982 for details): in the 1920s by the Whitney South Sea Expedition for the American Museum of Natural History, New York (account in several issues of American Museum Novitates); in the 1960s by the Museum National d’Histoire Naturelle (Lacan & Mougin 1974); in the 1970s by the Ecole Pratique des Hautes Etudes (Holyoak & Thibault 1984); and since 1980 by several institutions and the Government of French Polynesia (e.g. Thibault & Varney 1991; Brooke 1995). The aims of this paper are to present comparative data on numbers and distribution of breeding seabirds of the Gambier Islands during the 20th century, using results from previous expeditions as well as recent data collected in 1995 and 1996.

The Bridled Tern Sterna anaethetusis a secretive tern species that is found only in the western part of the Pacific Ocean. Its breeding in New Caledonia has been questionable for decades. We document its breeding in the southern part of New Caledonia, and present the first information on breeding and biometrics of this species there. Overall, this population appears to be very similar to the Australian population, except that it is slightly larger. The total known population is between 750 and 1500 breeding pairs.

The fruticose thallus of mature Cladina subtenuis is characterized by a variable branching pat- tern. While the shape of the mature thallus is not easily predictable, early branch initiation follows a highly predictable pattern. Branching is determined by meristemlike bundles of fungal cells located at the apices of the thallus. When the bundles split, branch- ing is initiated. Meristem growth is limited to a uni

The breeding populations of many waterbirds in the Gediz Delta near Izmir in Western Turkey are of considerable importance for the Mediterranean basin. Up to 35 pairs of Dalmatian Pelican (Pelecanus crispus), a globally endangered bird species, breed in the area. The breeding populations of Mediterranean Gull (Lorus melanocephalus), Caspian Tern (Sterna caspia), Sandwich Tern (Sterna sandvicensis), and Common Tern (Sterna hirundo) are significant in terms of the entire Mediterranean population. Breeding of the Sandwich Tern was recorded in Turkey for the first time.

Breeding of Roseate Terns Sterna dougallii on the northern Great Barrier Reef (11°-15°S) was monitored between 1976 and 1994, and they were recorded breeding on the inshore rocky islands in most years, usually starting April-May. Between 50-5000 pairs were recorded breeding each year and indicate that the northern Great Barrier Reef is an important breeding area for Roseate Terns during peak years when large colonies of 1000-5000 pairs formed on low sand cays in the far northern Great Barrier Reef (11°s). On at least three occasions, breeding success was poor in these large colonies, with high mortality of the almost-fledged chicks. Growth in weight and wing length of Roseate Tern chicks was measured at Eagle Island (14°42′S) between 1983 and 1986 in order to assess the influence of food on growth rates and survival. Chicks took up to 35 days to fledge, significantly longer than the ecologically similar, more numerous Black-naped Tern Sterna sumatrana at the same site at the same time and also almost 10 days longer than Roseate Tern chicks from temperate North American colonies. These data suggest that conditions in northern Australia are rarely favourable for the rapid growth and breeding success of Roseate Terns. Pelagic fish populations around inshore islands in tropical Australia may only be able to support limited numbers of Roseate Terns during the breeding season. This makes northeastern Australian populations of this globally threatened species extremely vulnerable to changes in the availability of their prey during the breeding season.

In this paper aspects of twice‐moulted primaries in Common Terns as described by Craik (1994) for Scotland are compared with those for The Netherlands. Similarity between the two populations is great. However the conclusions drawn are different. In the Scotland study it was concluded that feeding conditions in the winterquarters determine the number of twice‐moulted primaries. Basing itself on birds of known age and on retraps in following years the study in the Netherlands states that the variation is a natural one, with a weak tendency of males and older birds to have slightly higher moulting scores. The second moult of the innermost primaries possibly functionally assures a rather fresh wing for the breeding season. It probably does not function as a distinguishing feature with the Arctic Tern, since, the Arctic Tern excepted, all terns breeding in Europe moult their innermost primaries twice. The colour difference between the old and new primaries and secondaries may have a social function within the ...

Trichomycetes (Zygomycota) are arthro- pod-associated fungi consisting of three orders, only one of which, the Harpellales, contains cultured spe? cies. Isozyme patterns were studied using starch gel electrophoresis of 108 isolates representing 18 de? scribed species from six genera of Harpellales (Cap- niomyces, Furculomyces, Genistelloides, Simuliomyces, Smittium, and Trichozygospora), and some unde? scribed species of Smittium, as well as three isolates of Amoebidium parasiticum (Amoebidiales) and three species of nontrichomycetous fungi. A total of 176 different band positions for 13 loci in 11 enzyme sys? tems were produced. The banding patterns were con? sistent with haploidy. Numerical taxonomic and prin- cipal coordinate analyses of Trichomycetes compared isozyme variation within and among described and undescribed species, including three named isolates of uncertain identity. There was no discernible pat? tern among the cultures attributable to geographic origin or type of insect host family. Isolates of de? scribed species produced similarity clusters that gen? erally correlated well with morphologically defined genera and species. Based on isozyme patterns, one isolate tentatively identified as G. hibernus was re-ex- amined and reclassified as C. stellatus. Thirty-six un? described isolates of Smittium produced seven clus? ters that probably represent new species. Other un? described Smittium isolates grouped with described species and may be conspecific. Cophenetic correla? tion coefficients for 13 clusters of Harpellales species were >0.90, but for A. parasiticum it was only 0.87; the latter may represent a species complex. Thirty- two isolates of Sm. culisetae originating from France, Australia, Japan, and six USA states (including Ha? waii) were isozymically very similar or identical to each other, despite differences in their geographic origins and dipteran host families. A phenogram based on isozyme patterns generally corresponded with one from a previous immunological study.

Summary Watson, J.J. & Kerley, G.I.H. 1995. A survey of the dune-breeding birds in the Eastern Cape, South Africa. Ostrich 66:15-20. Increasing human activity in sensitive dune areas may negatively impact dune-breeding birds. The aim of this study was to survey populations of dune-breeding birds along 237 km of sand and dune coastline between Huisklip and The Great Fish River, Eastern Cape. The numbers of Whitefronted Plovers Charadrius marginatus, African Black Oystercatchers Haematopus moquini and Damara Terns Sterna balaenarum were recorded in 33 sections along the coast. A total of 589 African Black Oystercatchers (2.49 birds/km), 537 Whitefronted Plovers (2.27 birds/km) and 28 Damara Terns (0.12 birds/km), were observed. Only one Damara Tern was seen outside the Alexandria Dunefield, which provides 74% of the total potential Damara Tern nesting sites in the Eastern Cape. The area between the Kabeljous and Maitland Rivers and between the Sundays River and Woody Cape (Alexandria Dunefield) are importan...

The Lesser Noddy Anous tenuirostris (melanops) is a small, dark-plumaged, tropical tern which breeds only on three islands in the Houtman Abrolhos, off Western Australia, where it nests in mangrove trees. On Pelsaert Island, in 1991, the single egg clutches were laid over a 102-day period from late August to early December, peaking in September. The incubation period averaged 34 days and the fledging period 40 days. Overall, 60% of eggs hatched and 47% gave rise to free-flying young. Storms caused extensive egg loss from the more exposed nests; some pairs laid replacement eggs. Birds laying earlier in the season tended to use more sheltered sites and, consequently, had a higher reproductive success than those laying later and in more exposed areas.

In 1989 and 1990 the number of twice‐moulted innermost primary feathers and the number of twice‐moulted outermost secondary feathers, which together form the pale mid‐wing panel in Common Terns, were recorded from birds caught during the breeding season at colonies in west Scotland. In each year, these numbers were positively correlated. The mean values of each, and of their sum, were significantly greater in 1990 than in 1989. There was no change in either number with age. There was no sexual difference in the number of twice‐moulted secondaries or in the sum of twice‐moulted primaries and secondaries; males had a slightly greater number of twice‐moulted primaries than females did in 1990 but not in 1989. It is suggested that this plumage characteristic of Common Terns may be used by birds as an aid to species recognition, particularly in distinction from the very similar Arctic Tern S. paradisaea at long range. The date of onset of primary moult in a captive Common Tern became earlier in each of the fir...

Birds can rid their bodies of heavy metals through both excretion and deposition in feathers, and females can also eliminate heavy metals in the contents of their eggs. In this paper the levels of heavy metals (lead, cadmium, mercury, selenium, manganese, chromium) in the contents and shells of eggs of roseate terns (Sterna dougallii) and herring gulls (Larus argentatus) nesting at Cedar Beach, Long Island, are reported. For both species, metal concentrations were significantly higher in the contents compared to the shells for lead, mercury, selenium, and chromium. For herring gulls, metal levels were higher in the shells for cadmium and manganese. Levels of cadmium, mercury, and selenium were significantly higher in roseate tern egg contents than for herring gulls. In eggshells, lead, cadmium, mercury, and selenium were significantly higher in roseate terns compared to herring gulls. For both species, eggshells account for about 7-8% of the egg by weight, but less than 1% of the egg burden for mercury, 1-5% for lead, selenium, and chromium, and 7-11% for manganese. For cadmium, shells account for only 5% of the egg burden for roseate terns, but 29% for herring gulls. These data suggest that, except for mercury, eggshells provide another method of excretion of metals in these two species of birds.

In tropical waters of the northern Great Barrier Reef, Australia, Crested Terns fed their young with prey from seven families of fish and the Order Decapoda; the majority was from the Family Clupeidae (herrings). This diet overlapped with that of the sympatric Black-naped Tern. Both species caught fish from four families in common, including pomacentrids that were a major prey item for Blacknaped Terns. Crested Terns fed their young larger prey-than Black-naped Terns and tended to feed further offshore, although their feeding ranges overlapped considerably. In each breeding season studied, laying by Crested Terns occurred after Black-naped Terns had finished. It is hypothesised that by feeding on smaller prey than Crested Terns, Black-naped Terns can reach breeding condition faster on smaller fish spawned early in the breeding season. Crested Terns may take longer to reach breeding condition feeding on small fish available early in the season or may delay breeding until fish spawned earlier in the summer season have grown to a suitable size. Crested Terns laid their eggs over short periods of not more than 27 days. This brief period at Eagle Island is shorter than that recorded at any other locality on the Australian coastline. Laying at Eagle Island was considerably more synchronous than for the whole of the central to northern region of the Great Barrier Reef. It is hypothesised that food pulses providing the resource necessary to permit breeding are brief at Eagle Island.

Common terns departed from their breeding colony together and in the same directions. However the low success foragers did not follow the more efficient feeders. This finding contrasts with the hypothesis that colonies may act as information centres in the common tern. We suggest that leaving colonies contemporaneously and in the same direction as a flock may be the results of different ecological pressures such as the predation; moreover clumped departures and arrivals may be related.

Seabirds in Madang Province waters were surveyed during 40 small-boat trips from 20 September to 27 November 1989. At least 11 579 individuals of 21 species were identified. None nested near Madang. The seasonal status, abundance, habitat distribution and day-roosting habits are reported for each species. Heinroth's Shearwater Puffinus heinrothi and Grey-backed Tern Sterna lunata are documented for the first time in mainland New Guinea waters, but at least the former is believed to be regular near Madang. Ten species of terns represented 93.7% of all seabirds. Seven boreal migrant species including Common Tern S. hirundo (69.1% of all identified seabirds) and Little Tern S. albifrons (6.0%) contributed 76.9% of the total. Twelve tropical species made up nearly all of the remainder. Total abundance was greatest in the inshore and harbour zones, but species diversity increased with distance offshore. Only six species (all terns) were seen roosting at only two sites on land or on a channel marker. Terns and boobies rested on any suitable flotsam, from coconuts to huge offshore rafts that included trees. Foraging distributions of these birds appeared to be influenced by the ephemeral distributions of both flotsam and feeding tuna schools. In the absence of flotsam, terns waiting for feeding tuna to resurface often settled on the water in dense flocks.

Summary Cooper, J., Brooke, R.K., Cyrus, D.P., Martin, A.P., Taylor, R.H. & Williams, A.J. 1992. Distribution, population size and conservation of the Caspian Tern Sterna caspia in southern Africa. Ostrich 63: 58–67. The Caspian Tern Sterna caspia occurs along the whole southern African coastline and on large river systems and water bodies away from the coast. A total of 28 definite breeding localities has been recorded in southern Africa. Breeding has occurred recently at at least 14 coastal localities between Swakopmund, Namibia, and Lake St Lucia, Natal, South Africa. Inland breeding has been recorded in recent years at Sua Pan, Botswana and Kalkfonteindam, Orange Free State, South Africa. Based on censuses conducted between 1980 and 1991, the southern African breeding population is estimated to be of the order of 500 pairs, 91% of which breed coastally and 89% breed on islands. Up to 290 pairs (58%) bred at Lake St Lucia. Seventyone per cent of the 1980–1991 breeding population falls within eight natu...