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Bird plumage and skin colour can be assessed from museum specimens. To determine whether these accurately represent the colours of live birds when viewed by birds themselves, we analysed the spectral reflectances of live and up to 100-year-old museum specimens of five seabirds species (White-faced Petrel Pelagodroma marina, Common Diving Petrel Pelecanoides urinatrix, Grey-faced Petrel Pterodroma gouldi, Little Shearwater Puffinus assimilis and Fluttering Shearwater Puffinus gavia). Live birds had brighter colours than museum specimens, but there were no significant differences in the wavelengths reflected. Modelling indicated that seabirds would be able to detect colour changes in the skin, but not the feathers, of museum specimens, but only for species with blue or pink feet (Pelecanoides urinatrix and Puffinis assimilis). For seabirds, museum specimens are adequate proxies for feather colour but not for skin colour. This article is protected by copyright. All rights reserved.

Our objective was to measure the concentrations of Hg, As, Cd, Co, Cr, Cu, Pb, Sb, V and Zn in the body feathers of grey-faced petrel (Pterodroma gouldi), fluttering shearwater (Puffinus gavia), little shearwater (Puffinus assimilis) and common diving petrel (Pelecanoides urinatrix) from breeding colonies in New Zealand between 2006 and 2013. The mean Hg concentration (36.48ppm; SD=9.59) in grey-faced petrel feathers was approximately 8.5 to 14 times that detected in the other three species sampled. We detected no trend or differences in Hg concentrations in grey-faced petrels over the 8years of this study, but Hg concentrations varied between breeding colonies although there was no strong relationship with latitude. The elevated Hg concentrations detected in grey-faced petrels could pose a risk to the breeding performance of grey-faced petrels and the customary harvest of chicks by Māori (New Zealand's indigenous peoples).

The diet and breeding ecology of Yellow-legged Gulls (Larus michahellis atlantis) were studied on Selvagem Grande, North Atlantic in the nesting season of 2007. We collected and analyzed 715 pellets from adults. The most frequent prey were White-faced Storm-petrels (Pelagodroma marina; present on 40.8% of all pellets) and the endemic land snails (Theba macandrewiana; present on 36.5% of all pellets). Other birds, namely Cory’s Shearwaters (Calonectris diomedea), Macaronesian Shearwaters (Puffinus assimilis), Bulwer’s Petrels (Bulweria bulwerii), and Band-rumped Storm-petrels (Oceanodroma castro) were relatively less frequent, but overall, seabirds were present in ca. 50% of all pellets, representing an estimated 60.4% of all mass consumed by gulls. We estimate that the contribution of seabirds to the overall caloric balance accounted for 82.5% of all energy consumed. The number of gull pairs breeding on Selvagem Grande was 12 on 2005 and 2007. Breeding success was low (0.92 and 0.25 juveniles per breeding pair, respectively). Using a simple bioenergetics model, we estimate the breeding gull population to have the potential to consume approximately 4,847 adult/sub-adult seabirds in 3.5 months in order to meet its energetic requirements. The importance of the estimated predation levels is discussed and some management actions are suggested.

The Portuguese island of Selvagem Grande (Great Salvage) in Macaronesia is an important seabird breeding station in the eastern Atlantic. Significant populations of Cory's shearwater Calonectris diomedea (Scopoli, 1769), Bulwer's petrel Bulweria bulweria (Jardine & Selby, 1828) and little shearwater Puffinus assimilis baroli (Bonaparte, 1857) are present, and white-faced storm-petrel Pelagodroma marina (Latham, 1790) and Madeiran storm-petrel Oceanodroma castro (Harcourt, 1851) populations are of global significance. Selvagem Grande also provides diverse habitats for an extensive flora, including 11 endemic species. The 270-ha island was also inhabited by two alien invasive mammals: the European rabbit Oryctolagus cuniculus (Linnaeus, 1758) and the house mouse Mus musculus (Linnaeus, 1758). Both are known to have had adverse impacts on breeding seabirds and island vegetation. In 2002, the Natural Park of Madeira conducted a program using brodifacoum bait formulations aimed at rabbit and mouse eradication. Approximately 17 000 individual baiting points were established on a 12.5 × 12.5 m grid. Baits were also applied by hand "seeding" on steep slopes and cliffs where bait stations could not be placed. Rabbits were removed after a month. However, mice persisted for considerably longer and strategic bait applications against them continued for a further six months. Subsequent assessments by trapping, bait takes and systematic observation of signs over three years, has confirmed the removal of both alien invasive species. This paper presents information on these operations, on measures adopted to mitigate adverse impacts of the eradication program on important vertebrate non-target species, including Berthelot's pipit Anthus berthelotii Bolle, 1862 and a species of gecko Tarentola bischoffi Joger, 1984 and on the initial response of the island's ecosystem to the eradication of rabbits and mice.

SUMMARY In this paper the bird bones collected in three separate localities on St. Helena during the British Ornithologists' Union Centenary Expedition to Ascension Island are catalogued and described. At Prosperous Bay there are deposits which appear to be only a few hundred years old, containing many intact bird bones, referable to Puffinus assimilis/lherminieri, Pelagodroma marina, Sula sula, Fregata ariel, and a new rail Aphanocrex podarces. In Dry Gut, north of Bencoolen, are apparently older deposits with bones of a medium-sized Pterodroma sp. and a humerus of Upupa epops. On Sugar Loaf Hill are extensive deposits which may be very old, containing fragmentary bones of a large Puffinus sp., of Puffinus assimilis/lherminieri, Pelagodroma marina, and at least one species of columbid. There is now evidence that thirteen species of oceanic birds have bred on St. Helena at some time (plus one—Sula leucogaster—whose status is still uncertain). Of these, only six species are now known to breed on the island, though two more may do so. The only surviving native land-bird is Charadrius sanctae-helenae, but at least three additional species were present in the past.

SUMMARY Seabird distributions were observed off Senegal during the upwelling season there, in February-March 1976, and are interpreted against an oceanographic background. Gannets Sula bassana, Pomarine Skuas Stercorarius pomarinus, Great Skuas Catharacta skua, Lesser Black-backed Gulls Larus fuscus, Black-headed Gulls L. ridibundus, Sandwich Terns Sterna sandvicensis and Royal Terns S. maxima were the dominant species on the shelf and slope adjacent to the inshore upwelling zone. Grey Phalaropes Phalaropus fulicarius were the only seabirds associated with an oceanic ‘front’ farther offshore; it is suggested that this and similar boundary zones are important feeding areas during the pelagic phase of this species' annual cycle. Leach's Storm-Petrels Oceanodroma leucorhoa were seen east to 20W, but the predominant storm-petrel of the waters between 23W and the continental slope was the Madeiran O. castro. It is suggested that the hatching period of Madeiran Storm-Petrels on the Cape Verde Islands is timed to take advantage of the arrival there of young fish in the surface waters, spawned off the African coast and drifted offshore. However Madeiran Storm-Petrels make no direct use of the coastal upwelling; nor do Little Shearwaters Puffinus assimilis or White-faced Storm-Petrels Pelagodroma marina, the other winter-breeding Cape Verdes seabirds, which probably feed close to the Islands. The Senegal upwelling is underexploited by seabirds, in contrast to comparable upwelling systems elsewhere. It is suggested that this is due to the seasonal timing of the upwelling, the scarcity of secure nest-sites for breeding seabirds, and the competing attractions of the Benguela upwelling in the South Atlantic.

Little Shearwaters, Puffinus assimilis assimilis, were thought to have disappeared from Lord Howe Island during the early 1900s. This study reports Little Shearwaters breeding on Lord Howe Island between 1990 and 2001. A survey in 2000 recorded 85 nestlings. It is unclear whether this species has persisted on Lord Howe Island in low numbers throughout last century or whether it is recolonising. Adults, ashore between April and October, often occupied burrows previously used by Black-winged Petrels, Pterodroma nigripennis. Observations at a single nest showed the incubation period to be 55 days and the nestling period to be 72 days. Chick mass increased at a mean rate of 5.2 g day–1 to a maximum of 272 g at 48 days old. The chick fledged on 5 November at 158 g after fasting for six days. During chick rearing, parents came ashore almost nightly, arriving just after sunset and remaining with the chick until shortly before dawn; occasionally they were ashore during the day.

The Black-winged Petrel, Pterodroma nigripennis, is a recent coloniser of Lord Howe Island, with adults present between late October and early May. Four nests were monitored during both the 1989-90 and 1990-91 breeding seasons. Eggs were laid at the end of December and hatching occurred in mid February after 45.3 ± 0.5 days' incubation (mean ± s.d.). Young (weighing 175.5 ± 8.7 g) fledged in early May, 84.8 ± 0.5 days after hatching and 10.3 ± 1.6 days after feeding stopped. On average, chicks were fed every 2.5 days, with each parent returning every 4.4 days. Provisioning rates remained constant throughout the period of chick rearing. Average meal size was estimated at 32.6 g. Inter-specifi c competition for nesting burrows with Little Shearwaters, Puffinus assimilis, was observed.

Aspects of the breeding ecology of the North Island little shearwater Puffinus assimilis haurakiensis were studied on Lady Alice Island during the 1994 breeding season. Burrows with banded breeding birds were monitored throughout the breeding season to the fledgling stage. Details of the mating, pre‐laying exodus, incubation and chick rearing periods are presented. These include timing of breeding, length of incubation shifts, weight changes during incubation, and chick growth parameters. Little shearwaters showed a very high level of breeding asynchrony, and we suggest that this is due to their relatively short breeding season, and the fact that they are non‐migratory. Several aspects of the chick‐rearing stage, including frequent feeding of chicks, were not compatible with theories that fat deposits in Procellariiform chicks are an adaptation either to an unreliable food supply, or to stochastic food provisioning by individual adults. We suggest that, unlike other species of Procellariiformes, ...

We examined the dimensions, nearest-neighbor distance, density, vegetation cover, shelter, and substrate of nest cavities in a multispecific colony of Procellariiformes: Cory's Shearwater (Calonectris diomedea), Little Shearwater (Puffinus assimilis), Bulwer's Petrel (Bulweria bulwerii), and Band-rumped Storm-Petrel (Oceanodroma castro). We investigated differences in nest cavity dimensions between species, the influence of nest cavity characteristics on hatching success of Cory's Shearwater and Band-rumped Storm-Petrel, and intra- and interspecific competition for nest cavities by using natural and artificial nests. Dimensions of nest cavities were highly correlated with species' body size. Physical features of the nests of Cory's Shearwater differed from those of small petrels. Physical features of the nests of small petrels overlapped extensively. Physical features helped to explain hatching success of Cory's Shearwater, and crowding influences contributed to hatching success of Band-rumped Storm-Petrel. Sheltered nest cavities had higher hatching success, but nest cavity characteristics interacted with the quality of breeders. Breadth and volume of eggs laid by Cory's Shearwater in artificial nests were significantly smaller than those in nearby natural nests, indicating that young breeders likely occupied artificial nests. Cory's Shearwater laid in half of the artificial nest cavities built for them, and excavated natural and artificial nest cavities of small petrels. We suggest that the breeding population of Cory's Shearwater includes high numbers of new breeders and is regulated by the availability of nest cavities. Results indicated that interference competition within and between Cory's Shearwater and small petrels is important in the structure of this procellariiform breeding community.

The pattern of chick feeding in Little Shearwater Puffinus assimilis on Selvagem Grande was examined by weighing chicks at 4–h intervals throughout eight successive nights and daily for a further 11 days (19 days in all). Individual meals fed to chicks averaged 23.2 g (s.d. ±4.7) or 13.6% of adult mass. Mass increments over 24 h (NET) were linearly related to the sum of positive mass increments over 4–h intervals during the night (SUM) by the equation NET = 0.36SUM - 5.89 (r2= 0.60). Using this relationship, I estimated that over a period of 18 nights, a mean of 95% of chicks were fed each night, and the mean interval between feeds was 1.05 nights, with a maximum of three nights. There was no significant day-to-day variation in feeding rate. These results were not compatible with the prevalent idea that the purpose of large fat deposits in Procellariiformes is to tide chicks over periodic fasts resulting from poor feeding conditions. On average, chicks required 16 g of food per day to maintain constant mass and converted 33% of their intake of food above this requirement into biomass. Meal size and feeding frequency were independent of chick size and body condition (body-mass corrected for body-size), and the masses of food received by individual chicks each night varied in direct proportion to previous values. These results suggest that the rate of food supply to chicks was not regulated by adjustment according to chicks' nutritional requirements. To some extent, this supports the hypothesis that lipid accumulation among Procellariiformes is related to stochastic variation in food supply rate, resulting from an absence of regulation of feeding. However, feeding was not stochastic, in that adults tended to deliver consistent amounts of food to their chicks, and the pattern of feeding among even the worst-fed chicks was inconsistent with a need for large lipid stores based upon chance variation in food delivery.

Correlations between lunar phase and behaviour have been studied in five different species of petrels (Cory's Shearwater, Calonectris diomedea; Little Shearwater, Puffinus assimilis; Bulwer's Petrel, Bulweria bulwerii; White-faced Storm Petrel, Pelagodroma marina; and Madeiran Storm Petrel, Oceanodroma castro) during 20 nights. Quantitative data on the activity of birds (number of calls per time unit, proportion of nests visited, and number of birds in flight by night), relatively to their breeding status and the phase of the moon, suggest that moonlight may affect primarily the activity of the nonbreeders, especially in the smaller species. The results are compared with those for other species of petrels and possible causes of moon avoidance, such as increased predation risk, are discussed.

The occurrence of scavenger seabirds at fishing trawlers was studied off Galicia, Spain. A total of 9,368 seabirds of 23 species were recorded during 92 fishing operations in 1998 and 1999. The most common species were the yellow-legged and lesser black-backed gull (Larus cachinnans and L. fuscus), Sabine´s gull (L. sabini), the northern gannet (Morus bassanus), the great shearwater (Puffinus gravis), sooty shearwater (P. griseus), the Manx and Balearic shearwater (P. puffinus and P. mauretanicus), the great skua (Catharacta skua) and terns (mainly Sterna hirundo and S. paradisaea). Other species occurred in small numbers: Leach´s petrel (Oceanodroma leucorhoa), the storm petrel (Hydrobates pelagicus), the little shearwater (Puffinus assimilis), Cory´s shearwater (Calonectris diomedea), the parasitic skua (Stercorarius parasiticus), the pomarine skua (S. pomarinus), the black-headed gull (Larus ridibundus), the glaucous gull (L. hyperboreus), the kittiwake (Rissa tridactyla), the sandwich tern (Sterna sandvicensis), the black tern (Chlidonias niger), the guillemot (Uria aalge) and the little auk (Alle alle). The maximum number of seabirds recorded at a haul was 320. The maximum number of a particular species ranged from 120 great shearwaters to 250 yellow-legged/lesser black-backed gulls during a single haul. The differences in ship-follower species abundance are related to migratory movements but fisheries could also have a strong influence at a smaller scale on the distribution of seabirds off Galicia. The degree to which seabirds rely on fishery discards as food was not quantified, but may be important for several species. Este trabajo estudia la asociación de aves marinas con barcos arrastreros que faenan sobre la plataforma y parte superior del talud continental de Galicia, NW España, desde junio de 1998 a marzo de 1999. Se registraron un total de 9.368 aves marinas de 23 especies durante 92 operaciones de pesca en 1998 y 1999. Las especies más comunes fueron el grupo gaviota patiamarilla y gaviota sombría (Larus cachinnans y L. fuscus), la gaviota de Sabine (L. sabini), el alcatraz atlántico (Morus bassanus), la pardela capirotada (Puffinus gravis), la pardela sombría (P. griseus), la pardela pichoneta y la balear (P. puffinus y P.mauretanicus), el págalo grande (Catharacta skua) y los charranes (principalmente Sterna hirundo y Sterna paradisea). Otras especies se observaron en menor número: el paiño de Leach (Oceanodroma leucorhoa), el paiño europeo (Hydrobates pelagicus), la pardela chica (Puffinus assimilis), la pardela cenicienta (Calonectris diomedea), el págalo parásito (Stercorarius parasiticus), el págalo pomarino (S. pomarinus), la gaviota reidora (Larus ridibundus), el gavión hiperbóreo (L. hyperboreus), la gaviota tridáctila (Rissa tridactyla), el charrán patinegro (Sterna sandvicensis), el fumarel común (Chlidonias niger), el arao común (Uria aalge) y el mérgulo atlántico (Alle alle). El máximo número de aves marinas registrado en un arrastre fue 320. El máximo número de una especie en particular en un arrastre osciló entre las 120 pardelas capirotadas a las 250 gaviotas patiamarillas y sombrías. Los resultados indicaron diferencias en la presencia para varias especies que están relacionados con los movimientos migratorios así como con la influencia de las pesquerías en aguas de Galicia que puede ser importante a escala regional. No se cuantificó el grado en el cual las aves marinas dependen de los descartes del arrastre pero puede ser importante para varias especies.

This paper reports the first comprehensive surveys of Fea's Petrel (Pterodromafeae), Bulwer's Petrel (Bulweria bulwerii), Manx Shearwater (Puffinus puffinus), Little Shearwater (Puffinus assimilis baroli) and two temporally-segregated forms of Band-rumped Storm-petrel (Oceanodroma castro) in the whole Azores archipelago, conducted from 1996 to 1998. Listening to nocturnal vocalizations was the main survey method. Breeding of Fea's Petrel was not confirmed and new sites of Bulwer's Petrel were not found (previous status: one site, 50 pairs), but previously undocumented colonies were identified for the remaining species. Manx Shearwater occurred in four colonies with 115-235 pairs (previous status: probable breeder), Little Shearwater occurred in 28 colonies with 840-1,530 pairs (previously: four locations, >150 pairs), hot-season Band-rumped Storm-petrels occurred in 5 colonies with 250-300 pairs (previously: two locations, 200 pairs) and cool-season Band-rumped Storm-petrels were found in eight locations with 665-740 pairs (previously: three locations, 600 pairs). Most colonies were confined to precipitous cliffs and islets, which may be a result of predation threats by introduced mammals. Although these surveys provided a valuable revision of the status and distribution for these species of conservation concern, further survey work is warranted and target areas are indicated. We discuss the potential and limitations of listening for nocturnal vocalizations as a method to survey and monitor shearwater and petrel populations in inaccessible habitats. Received 24 May 1999, accepted 8 July 1999.