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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.

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.

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.