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This is the first study using geolocators (global location sensing, GLS) to track the movements of a pelagic tropical seabird. We used GLS to describe at-sea distribution and activity patterns of wedge-tailed shearwaters Puffinus pacificus breeding on Aride Island, Seychelles, in the late chick-rearing, non-breeding and pre-breeding periods. During late chick-rearing and pre-breeding periods, shearwaters foraged relatively close to the colony. In the non-breeding period, shearwaters; were found on a west-east gradient along the equator, between 5 degrees N and 10 degrees S. Some of the tracked individuals showed little dispersion, staying as close as 1000 km to Aride Island, while others travelled 3500 km to the Central Indian Ocean Basin. Individual core areas of activity showed little overlap. Overall, wedge-tailed shearwaters showed short-distance movements and exploited relatively unproductive oceanic waters. At-sea distribution largely matched that of yellowfin and skipjack tunas, emphasising the importance of the association with subsurface predators rather than associations with physical oceanographic features that enhance primary productivity. During the non-breeding period, the feeding activity of, shearwaters was mainly concentrated in the daylight period, when tunas also forage. A different behaviour, characterised by a much lower proportion of the night sitting on the sea surface, was recorded in the pre-laying exodus of 1 female to more productive waters, suggesting a different feeding strategy and/or targeting of different prey. Knowledge of the at-sea distribution of wedge-tailed shearwaters allows quantification of the overlap with industrial fisheries, which will be crucial to devise fisheries policies for the Indian Ocean with important implications for the conservation of this species.

SummaryThe problem of establishing the breeding status of burrowing birds is compounded by the inaccessibility of long meandering burrows. A solution, involving manipulation of a mini video camera and monitor, using infra-red light is presented which enables efficient, reliable recording of burrow occupancy with minimum disturbance to the birds and burrows. It was designed to establish the breeding status of the Wedge-tailed Shearwater Puffinus pacificus in the Capricorn Group of islands, Great Barrier Reef, but with proper screening and possibly, further modification, its use need not be site or species specific.

A bird survey was carried out with the assistance of the French Navy at the Chesterfield Islands, from 12 to 16 December 2005. Eleven species were observed on Loop Islet, including six breeding seabirds (brown booby, red-footed booby, masked booby, wedge-tailed shearwater, black noddy, common noddy), two non-breeding seabirds (sooty tern, Pacific frigatebird), two shorebirds (ruddy turnstone, tattler) and the buff-banded rail. The abundance of wedge-tailed shearwater and red-footed booby, estimated to reach around 1% or more of the entire Pacific population, make of the Chesterfield archipelago an area of global importance for their conservation. Loop Islet is also a nesting site for the green turtle.; Une mission de recensement des oiseaux a été menée avec le concours de la Marine nationale aux îles Chesterfield, du 12 au 16 décembre 2005. Onze espèces d'oiseaux ont été observées et recensées sur l'îlot Loop, dont six oiseaux marins nicheurs (fou brun, fou à pieds rouges, fou masqué, puffin fouquet, noddi noir, noddi brun), deux oiseaux marins non nicheurs (sterne fuligineuse, grande frégate), deux limicoles (tournepierre à collier, chevalier non identifié) et un râle (râle à bandes). Les abondances du puffin fouquet et du fou à pieds rouges, estimées à environ 1% ou plus de leurs effectifs pour tout le Pacifique, font de l'archipel des Chesterfield une zone d’importance mondiale, prioritaire pour leur protection. L’îlot Loop est aussi un site de ponte pour la tortue verte.

A brief visit to Monuriki, an island in Fiji’s Mamanuca group was completed in March-April 2011 to gather baseline data on the island’s population of Wedge-tailed Shearwaters Puffinus pacificus prior to the eradication of alien invasive Polynesian Rat Rattus exulans and feral goats Capra hircus from the island in December 2011. We estimated an island-wide population of 2,000-5,500 pairs of Wedge-tailed Shearwaters, the largest population recorded in Fiji. Productivity was estimated to be 40%. It is anticipated these baseline figures will be used to assess the impacts that the removal of invasive mammals has on the population.

1. 1. The water loss from naturally incubated eggs of the Wedge-tailed Shearwater was measured, together with the water-vapor pressure of the incubated egg's micro-climate, the egg temperature, the water-vapor conductance of the shell and other characteristics of the shell. 2. 2. The mean daily water loss (.MH2O) from the eggs (154.6 mg/day) was only 49.8% of the value expected on the basis of the mass of the freshly-laid egg. The low value for MH2o was attributed largely to a low water-vapor conductance (GH2O) of the shell (56.9% of predictions). The low GH2O. in turn, was due to fewer pores in the shell. 3. 3. Egg temperature (35.0 C) was lower than that of the eggs of birds in general, and this was considered to be a contributory factor to the low daily water loss. 4. 4. The water-vapor pressure (PH2Onest) of the egg's microclimate (19.57 torr) was similar to that of many surface-nesting birds in spite of the burrow-nesting habits of the shearwaters. 5. 5. It was calculated that the total pre-pippiny water loss from the eggs represented 12.2% of the initial mass of egg. 6. 6. It was concluded that prolonged incubation in the Wedge-tailed Shearwater, as in other smaller Procellariiformes. is associated with reduced values for .MH2O and GH2O and fewer pores in the shell.

Growth studies of a tropical seabird, the Wedge-tailed Shearwater (Puffinus pacificus), were conducted over 3 yr at three locations in Hawaii. Basic growth patterns of body dimensions are described. The range of asymptotes and maximal recorded weights suggests that feeding and the availability of food may influence growth from year to year and in different colonies within the same year.

At low air temperatures (2.3–13.9°C), Wedge-tailed Shearwaters (Puffinus pacificus) shivered and their oxygen consumption increased to as much as 283% of the mean value (0.77 ml O2/g·h) within the thermoneutral zone of air temperature (23–34°C). The minimal thermal conductance of the tissues and plumage was similar to the value predicted from the body mass (320.5 g). The oxygen consumption of the birds within their thermoneutral zone was lower than predictions based on body mass. At elevated air temperatures, the shearwaters panted at respiratory frequencies as high as 260 respirations/min; maximal respiratory frequencies were not invoked until the birds had become hyperthermic. During exposure to a hot environment, the oxygen consumption of the birds increased and in most instances the shearwaters were not able to lose heat equivalent to their concurrent metabolic heat production.

The sequence of events during the prolonged pipping process in the Wedge-tailed Shearwater (Puffinus pacificus) was chronicled. The initial event, a series of star-fractures in the shell, occurred five to six days before the chick hatched. The daily rate of water loss from pipped eggs was considerably greater than that from unpipped eggs; the highest water loss (858.4 mg/day) occurred in eggs with a distinct pip-hole. It was estimated that approximately 16% of the water loss from eggs with a pip-hole could be attributed to embryonic pulmonary ventilation. Comparison with three other species of procellariiform sea birds with a seven-fold range of egg mass, revealed that the total water loss from the egg over the entire incubation period varied from 16.1 to 18.6% of the fresh egg mass. The main difference between the four species lay in the way in which the water loss was divided between the pre-pipping period and the period between the initiation of pipping and hatching. The initial event in the pipping process of the eggs of many species of birds is the penetration, by the embryo's beak, of the air cell at the blunt pole of the egg, an event that has been termed "internal pipping" (Ar et al. 1980). Internal pipping allows the embryo to rebreathe the air in the aircell but it has little effect on the water loss from the egg, because the integrity of the egg shell, which presents the main barrier to the diffusion of water vapor out of the egg (Paganelli 1980), is intact. Following internal pipping, a series of star-fractures is made in the shell, by the embryo, and, subsequently, a distinct hole -the "pip-hole"is made in the shell. Both of these events are likely to result in an increased rate of water loss from the egg (Whittow 1980), because the water loss is then no longer limited by the number and size of the minute pores in the shell, through which gases diffuse. In the eggs of the Wedge-tailed Shearwater (Puffinus pacificus) the sequence of events during pipping differs markedly from that just described. In this species, the initial event in the pipping process is a series of starfractures in the shell (Ackerman et al. 1980), an event that we have called "external pipping" (Grant et al. 1982a). In addition, the duration of the pipping process-from the initial star-fractures in the shell, to the hatching of the chick-is relatively long (Ackerman et al. 1980, Whittow 1980). It seemed likely, therefore, that a substantial fraction of the total water loss from the egg of the Wedgetailed Shearwater might occur during the pipped phase of incubation. We conducted a study to document the sequence of events during pipping and to measure directly the water loss during the pip-to-hatch period. An ancillary objective was to estimate the contribution of embryonic pulmonary ventilation to the water loss during this period. PROCEDURES AND METHODS Observations in the field were made on Manana Island, a small island off the main island of Oahu, Hawaii. Eggs of know age were carefully examined on alternate days in late July and August 1979, in order to chronicle the events during pipping in naturally-incubated eggs. Internallypipped eggs were identified by "peeping" and/or breathing sounds made by the chick, aided by auscultation with a bell stethoscope. The mass loss of externally-pipped eggs was also measured on Manana; the eggs were weighed to 0.01 g at intervals of 46.9-72.6 h on an Ohaus balance (m del 1010-10). Other hearwater eggs were collected and incubated in the laboratory at 360C (relative humidity 40%). The eggs were four to five weeks old when first placed in the inc bator; the eggs were turned twice daily before external pipping. The artificially incubated eggs were weighed periodically o measure the pre-pipping daily water loss (Ackerman et al. 1980). After the initial star-fracture of the shell had occurred, the eggs were weighed daily. The respiratory water loss (rhiH20, g/h) from the embryo after internal pipping was calculated from the following equation: rhHO = VE (ecx 0 ein) VE = mean pulmonary ventilation (1/h) reported for the shearwater's embryo (Pettit and Whittow 1982) eex = water vapor content of expired air (g/l) derived from