Wedge-tailed Shearwater Puffinus Pacificus Research Articles

Stibarokris mariasi sp. nov. - a new quill mite species (Acariformes: Syringophilidae) parasitizing Puffinus pacificus (Gmelin) (Procellariidae) on Johnston Atoll.

A new quill mite species Stibarokris mariasi sp. nov. (Acariformes: Syringophilidae) is described from the Wedge-tailed Shearwater Puffinus pacificus (Gmelin) (Procellariiformes: Procellariidae) from Johnston Atoll. Females of S. mariasi sp. nov. differ from most similar species S. phoeniconaias Skoracki and OConnor, 2010 by the longitudinal branch of the peritremes consisting of 11-14 chambers (vs 15-17 chambers in S. phoeniconaias), the movable cheliceral digit 145 long (vs 170), setal bases c1 situated distinctly anterior to the level of setae se (vs setal bases c1 and se situated at the same transverse level), the propodonotal shield punctate on the whole surface (vs propodonotal shield punctate at the lateral margins), the small, balloonlike hysteronotal shield, bearing bases of setae d1 and densely punctate on the whole surface (vs hysteronotal shield bearing setal bases d1 and e2 and punctate at the anterior part), the pseudanal setae ps1 1.8 times longer than setae ps2 (vs setae ps1 and ps2 subequal in length), subequal lengths of setae h1 and f1 (vs setae h1 twice longer than f1) and the lengths of setae ag1, ag2, and ag3 145-170, 105-125, 120-165, respectively (vs ag1, ag2 and ag3 245-285, 245-270, 330-340, respectively). A key to all known species of the genus Stibarokris Kethley, 1970 is proposed.

Divergence in chick developmental patterns among wedge-tailed shearwater populations

Mechanisms of population divergence in seabirds are poorly understood. We evaluated whether divergent patterns of chick development among wedge-tailed shearwater Puffinus pacificus populations are facultative responses to short-term fluctuations in food availability, or fixed colony-specific phenomena potentially associated with differences in local resource availability. Supplementary feeding at Heron Island increased food intake to levels equal to, or greater than, those observed at Lord Howe Island. In supplemented chicks, mass accumulation per gram of food received was inversely related to current body stores, up to a maximum storage level set by body size. Significantly, maximum storage was lower for Heron Island than for Lord Howe Island chicks at equivalent body size. In contrast, relative allocation to skeletal growth did not differ between supplemented and control chicks, was not influenced by body condition and did not increase to levels observed at Lord Howe Island. Overall, the present study showed that supplemented chicks were unable to use short-term increases in food availability to increase relative mass stores or rates of skeletal development, implying that both life-history parameters have some colony-specific components that are divergent between the locations of this study. Our findings add weight to previous studies suggesting that phenotypic plasticity and/or genetic drift due to philopatry cannot fully explain patterns of morphological, behavioural and physiological divergence among these 2 shearwater colonies.

A pre-eradication survey of Wedge-tailed Shearwater Puffinus pacificus on Monuriki, Mamanuca Group, Fiji

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.

When seasnake meets seabird: Ecosystem engineering, facilitation and competition

Ecosystem engineers such as burrowing seabirds can increase habitat availability for sympatric taxa – but only if the burrow's owner allows other species to use the newly created shelter site. Our studies on a small Pacific island suggest that an avian burrower (the wedge-tailed shearwater Puffinus pacificus) is both a facilitator and a competitor for amphibious seasnakes. Video camera inspection of 102 burrows revealed frequent usage of these burrows as retreat sites by the snakes, with Laticauda laticaudata restricted to burrows <4 m from the water's edge, whereas Laticauda saintgironsi often used burrows further inland. Snakes never occupied burrows that contained adult shearwaters, suggesting active burrow defence by the birds. Model snakes that we inserted into burrows were attacked, especially on the head and upper body, and we found one snake pecked to death outside a burrow. Wedge-tailed shearwaters act as facilitators, creating a thermally favourable microhabitat and substantially enhancing habitat suitability for snakes; but they are also competitors, aggressively competing with snakes for occupancy of the resource that has been created.

Movements, at-sea distribution and behaviour of a tropical pelagic seabird: the wedge-tailed shearwater in the western Indian Ocean

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 391:231-242 (2009) - DOI: https://doi.org/10.3354/meps07717 Movements, at-sea distribution and behaviour of a tropical pelagic seabird: the wedge-tailed shearwater in the western Indian Ocean Teresa Catry1,*, Jaime A. Ramos1, Matthieu Le Corre2, Richard A. Phillips3 1Instituto do Mar (IMAR), Departamento de Zoologia, Universidade de Coimbra, 3004-517 Coimbra, Portugal 2Laboratoire ECOMAR, Université de la Réunion, 97715 Saint Denis message cedex 9, France 3British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge CB3 0ET, UK *Email: teresa_catry@yahoo.com ABSTRACT: 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°N and 10°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. KEY WORDS: Wedge-tailed shearwater · Activity patterns · At-sea distribution · Foraging behaviour · Pelagic · Habitat preferences · Indian Ocean · Tuna distribution Full text in pdf format PreviousNextCite this article as: Catry T, Ramos JA, Le Corre M, Phillips RA (2009) Movements, at-sea distribution and behaviour of a tropical pelagic seabird: the wedge-tailed shearwater in the western Indian Ocean. Mar Ecol Prog Ser 391:231-242. https://doi.org/10.3354/meps07717 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 391. Online publication date: September 28, 2009 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2009 Inter-Research.

Geographical variation in the morphology of the Wedge-tailed Shearwater (Puffinus pacificus)

Geographical variation in the morphology of the Wedge-tailed Shearwater (Puffinus pacificus) was assessed using multivariate analyses, including MANOVA and canonical discriminant analysis. This study tested the roles of climatic (sea surface temperature) and geographical (latitude, longitude and inter-population distance) factors as potential agents of natural selection on the body dimensions of this geographically variable species. Patterns of morphological variation, represented by phenotypic distances, were found to be unrelated to the geographical proximity of colonies. The Wedge-tailed Shearwater exhibited the trend in body size predicted by Bergmann's Rule, increasing significantly with increasing latitude and decreasing temperature. Allen's Rule proposes that an animal's extremities should be relatively shorter in colder climates, but the data did not support this hypothesis with regards to variation in bill-shape of the Wedge-tailed Shearwater. Owing to the interrelated nature of ecological parameters, such as food, climate, distribution, life history and breeding biology, it is unlikely that a single factor is responsible for the observed morphological variation. However, food, through its influence on competition, dispersal, growth, fecundity and survival, may play an important role in the patterns of morphological variation found in this study. Therefore, the heterogeneity of the foraging habitat over the range of the species may be responsible for the observed variation, owing to differences in the distance required to travel to the feeding grounds and the availability and quality of food.

Breeding numbers and population trends of Wedge-tailed Shearwater (Puffinus pacificus) and Black Noddy (Anous minutus) in the Capricornia Cays, southern Great Barrier Reef

Wedge-tailed Shearwaters and Black Noddies are the two numerically dominant seabird species found in the southern section of the Great Barrier Reef, Australia. This research provides baseline breeding population estimates for nine of 16 islands in the Capricornia Group over five years for Shearwaters (1996–2000) and four years for Noddies (1997–2000). With estimates of ∼302000 active breeding pairs of Black Noddies and ∼560000 breeding pairs of Wedge-tailed Shearwaters in the area, the research results have confirmed the importance of the Capricornia Group as a recognised breeding area for these birds.

Colony-specific foraging behaviour and co-ordinated divergence of chick development in the wedge-tailed shearwater Puffinus pacificus

We examined divergence in foraging, provisioning and chick developmental patterns between wedge-tailed shearwaters Puffinus pacificus breeding at a temperate (Lord Howe Island) and sub-tropical (Heron Island) location. We aimed to evaluate the potential for different foraging environments to cause co-ordinated adaptive divergence in these characteristics. Adult foraging and provisioning behaviour differed significantly between locations, reflecting lower near-colony resource availability at Heron Island. Chick developmental patterns also differed significantly between locations. Overall, chicks at Lord Howe Island grew faster and had greater skeletal growth per gram of food delivered. In contrast, chicks at Heron Island exhibited greater body mass gains per gram of food delivered. Based on previously observed physiological or facultative responses to changes in provisioning rates in seabirds and long-term patterns of primary productivity at each location, we propose these developmental differences reflect colony-specific physiological adaptations to differences in long-term provisioning rates. If so, our results suggest co-ordinated environmentally determined divergent coevolution of chick and adult life-history parameters between these 2 locations.

Dual-foraging and co-ordinated provisioning in a tropical Procellariiform, the wedge-tailed shearwater

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 301:293-301 (2005) - doi:10.3354/meps301293 Dual-foraging and co-ordinated provisioning in a tropical Procellariiform, the wedge-tailed shearwater Bradley C. Congdon*, Andrew K. Krockenberger, Brian V. Smithers School of Tropical Biology, James Cook University, PO Box 6811, Cairns, Queensland 4870, Australia *Email: brad.congdon@jcu.edu.au ABSTRACT: To sustain breeding while simultaneously compensating for poor local resource availability, many temperate Procellariiformes (tube-nosed seabirds) access highly productive areas ‘at-distance’ from breeding colonies using a unique dual-foraging strategy. We tested for, and observed, a similar dual foraging strategy in a tropical Procellariiform, the wedge-tailed shearwater Puffinus pacificus. Foraging adults repeatedly performed short-trip cycles of multiple 1 to 4 d trips followed by a single long-trip of ~8 d. As with temperate species, wedge-tailed shearwaters used long-trips to build body reserves that they passed onto chicks by not self-provisioning adequately during the early stages of each short-trip cycle. Unlike temperate species (1) long-trip length and adult mass change during long-trips was inversely related to adult mass at the beginning of the same long-trip, and (2) foraging mode changeover appeared to be co-ordinated and was not initiated by adults reaching some critical lower mass. This implies that the dual-foraging pattern observed in wedge-tailed shearwaters is a consequence of the median time adults require to replenish body reserves on long-trips. We conclude that foraging strategies in wedge-tailed shearwaters vary spatially relative to near-colony resource availability, and that dual-foraging is a general Procellariiform life-history strategy used to address similar ecological constraints in both temperate and tropical systems. Our findings suggest that wedge-tailed shearwaters of the southern Great Barrier Reef (GBR) may be dependent on localised areas of high productivity ‘at-distance’ from breeding colonies to sustain breeding. KEY WORDS: Dual-foraging · Co-ordinated provisioning · Feeding ecology · Wedge-tailed shearwater · Puffinus pacificus · Procellariiform · Great Barrier Reef Full text in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 301. Online publication date: October 11, 2005 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2005 Inter-Research.

Sea surface temperature constrains wedge-tailed shearwater foraging success within breeding seasons

Processes that underlie impacts of global warming on marine organisms at upper trophic levels are largely unknown. Long-term studies of seabirds indicate that inter-annual decreases in fledging success are correlated with El Nino years, when sea surface temperatures (SSTs) are above long-term averages. These studies propose that seasonal processes are most likely responsible. To date, no work has focused on the potential impacts of elevated SSTs on seabird reproduction at finer time scales, i.e. within a breeding season. We directly measured the influence of SST variability on foraging success in the wedge-tailed shearwater Puffinus pacificus within and among 3 breeding seasons at Heron Island in the southern Great Barrier Reef, Australia. We found that changes in foraging success (meal size and feed frequency) and chick growth were negatively correlated with daily variations in SST both within and among seasons. Our findings suggest that forage resource availability fluctuated daily in direct association with small-scale variation in SST. This is evidence that declines in seabird breeding success, previously coupled exclusively with large-scale El Nino conditions and processes, may also involve fine-scale mechanisms. Consequently, observed El Nino scale impacts may include season-specific outcomes of day-to-day trophic interactions that operate within all breeding seasons.

THE CHANGING STATUS OF MARINE BIRDS BREEDING AT SAN BENEDICTO ISLAND, MEXICO

We reviewed the status of the breeding marine birds on San Benedicto Island, Mexico, based on >100 years of published observations and seven of our own surveys conducted between 1978 and 2000. We found that there have been marked changes in the island avifauna with two main trends evident. First, a volcanic eruption destroyed much of the island in 1952. The Wedge-tailed Shearwater (Puffinus pacificus; estimated breeding population 1,000 pairs), Townsend's Shearwater (Puffinus auricularis; probable breeder, small numbers), and Red-footed Booby (Sula sula; 60 pairs) historically had much larger populations, but they apparently never fully recovered from the eruption. The Masked Booby (Sula dactylatra; 2,185 pairs), however, has become much more abundant perhaps due to changes in the vegetation. The second trend is that within the last three decades at least two, and possibly four, species from the central Pacific have colonized the island. The Laysan Albatross (Phoebastria immutabilis; 12 pairs) started breeding in the late 1980s; Black-footed Albatross (Phoebastria nigripes; 1 pair) in 2000. Red-tailed Tropicbirds (Phaethon rubricauda; probable breeder, 10 pairs) may have started breeding in the 1980s, and at least some of the breeding Brown Boobies (Sula leucogaster; 300 pairs) are from central Pacific populations. The reason(s) for this influx of central Pacific species is unknown, but likely involves changes in the marine environment. Other breeding species include the Red-billed Tropicbird (Phaethon aethereus; 200 pairs), Nazca Booby (Sula granti; 50 pairs), Great Frigatebird (Fregata minor; 165 pairs), and Magnificent Frigatebird (Fregata magnificens; 5 pairs).

PARENTAL PROVISIONING PATTERNS OF WEDGE-TAILED SHEARWATERS AND THEIR RELATION TO CHICK BODY CONDITION

Abstract I studied the provisioning patterns of a subtropical, northern-hemisphere procellariiform, the Wedge-tailed Shearwater (Puffinus pacificus) and measured the responses of parents to chick body condition. Foraging trip length, meal size, delivery rate, and chick body condition were measured during nesting periods in 1996 and 1997. Wedge-tailed Shearwaters adopted a unimodal foraging strategy with foraging trips that averaged 1.5 to 2 days duration and averaged about 40–50 g of food per trip. The rate of food delivery (g of food per day spent foraging) decreased with increasing trip duration, such that one-day trips resulted in the greatest rate of food delivery to the nest in both 1996 and 1997. Chicks left in poorer body condition were more likely to receive visits from one or both adults the following evening (1996 and 1997) and received larger meals (1996) than those left in better condition. Although foraging strategies may differ from subpolar and temperate shearwater species, rates of food de...

Chick-provisioning behaviour of two shearwaters breeding in south-eastern Australia

The chick-provisioning behaviour of the short-tailed shearwater Puffinus tenuirostris and the wedge-tailed shearwater Puffinus pacificus was investigated in a mixed colony on Montague Island, New South Wales, Australia, over two breeding seasons. This colony is located at opposite edges of the breeding distribution of the two species. Frequent weighing techniques were used to determine chick feeding frequency, feed timing, meal size, chick weight loss and indices of food conversion efficiency of the chicks. Short-tailed shearwater parents fed their chicks larger more infrequent meals than wedge-tailed shearwater parents. Short-tailed shearwater chicks demonstrated higher food conversion efficiencies and lower weight loss than wedge-tailed shearwater chicks, indicating either differences in diet or metabolic rates. The feeding frequency in wedge-tailed shearwaters also fluctuated more widely than for short-tailed shearwaters over the two breeding seasons. Despite the fact that the timing of the breeding cycle on Montague Island is almost identical for the two species, these differences in chick provisioning are probably a result of differences in prey type and location, so they may help explain variations in annual breeding success and limits to the distribution of the two species.

Metals in Feathers of Bonin Petrel, Christmas Shearwater, Wedge-Tailed Shearwater, and Red-Tailed Tropicbird in the Hawaian Islands, Northern Pacific

Levels of environmental pollutants are usually higher in mainland and coastal areas than in offshore or oceanic islands due to higher inputs from agricultural and industrial sources. Levels of heavy metals are usually higher in adult than in young birds, because they have had longer to accumulate metals in their tissues, and/or because they may eat larger, more contaminated, prey. We examined the levels of arsenic, cadmium, chromium, lead, manganese, mercury, and selenium in the adults and young of Bonin petrel (Pterodroma hypoleuca), Christmas shearwater (Puffinus nativitatis) and red-tailed tropicbird (Phaethon rubricauda) on Midway Atoll, and adult wedge-tailed shearwater (Puffinus pacificus) on Midway Atoll and on Manana Island (off Oahu) in the northern Pacific. All birds were analyzed individually except for Christmas Shearwater chicks where samples were pooled to obtain sufficient quantities for analysis. Significant (p<0.05) age-related differences were found for mercury, selenium, manganese and chromium in Bonin petrels, for selenium and mercury in Christmas shearwaters, and for chromium and mercury in Red-tailed Tropicbirds. Lead approached significance for all three species. Adults had higher levels than young except for chromium and manganese in the petrels and arsenic in all three species. There were significant interspecific differences in concentrations of all metals except arsenic for the adults nesting on Midway. Christmas shearwaters had the highest levels of all metals except mercury and chromium. Bonin petrels, the smallest species examined, had mercury levels that were over three times higher than any of the adults of the other three species. For wedge-tailed shearwaters, levels of chromium and lead were significantly higher, and manganese and selenium were lower on Midway than Manana. Knowledge of the foraging ranges and habits of these far-ranging seabirds is inadequately known, but does not currently explain the observed differences among species. We could not find a consistent pattern of differences between the burrow nesting species (Bonin petrel, Wedge-tailed shearwater) and the surface nesting tropicbirds. There was no consistent pairwise correlation between any metals across all species.

Breeding Cycle of Wedge-tailed ShearwatersPuffinus pacificusat Heron Island, Great Barrier Reef

Heron Island (23'27'S, 151°55'E), is a small coral cay of the southern Great Barrier Reef, one of several cays constituting the Capricorn Group of islands which supports a large breeding colony of Wedge-tailed Shearwater Puffinus pacificus. These birds excavate burrows for nesting in suitable ground, and nest colonially (Warham 1990). To date, only breeding population estimates, burrow incubation rates, and a preliminary investigation into hatching success have been made at this locality (Gillham 1963; Shipway 1969; Ogden 1979, 1994; Hulsman 1984a; Hill & Barnes 1989; Dyer 1992; Dyer & Hill 1992; Ogden 1994; Hill et al. 1995). This study was based at Heron Island during the 1993-94 breeding season and describes the timing of the breeding cycle, particularly the hatching and fledging phases.

Population Size of the Wedge-tailed Shearwater Puffinus pacificus Population in Pisonia grandis Forest on Heron Island in 1992

Repeated counts of Wedge-tailed Shearwater Puffinus pacificus burrows were made in two 30 × 30 m permanent plots in Pisonia grandis forest on Heron Island in 1978,1979 and 1992. The results support the population estimates of Hill & Barnes (1989) and their suggestion that the shearwater population almost doubled (to c. 16 000 pairs) between 1983 and 1985. However, due to the wide confidence limits on most estimates, a more gradual increase (of c. 3% per annum) cannot be ruled out. The 1992 population estimate was 16 503 ± 3427 pairs. Because shearwaters are supposedly faithful to nesting sites, the increase poses questions about inter-island movement and social organisation within colonies. It may also present problems for management of the Heron Island population.

Embryonic heart rate and oxygen pulse in two procellariiform seabirds, Diomedea immutabilis and Puffinus pacificus

Developmental patterns of embryonic heart rate were measured non-invasively in two procellariiform seabirds, the Laysan albatross (Diomedea immutabilis) and wedge-tailed shearwater (Puffinus pacificus), during prepipping and after pipping. The O2 pulse, defined as the O2 consumption per single heart beat, was calculated using the previously reported O2 consumption for these species. The embryonic heart rate of the albatross was not changed by internal pipping (initial pipping event in this species), remained unchanged during the prolonged internal pipping period and tended to increase, although insignificantly, with the initiation of external pipping (second pipping event). Heart rate in the shearwater remained unchanged during the late prepipping stages, did not change with external pipping (initial pipping event), but increased during the prolonged internal pipping period (second pipping event) and reached a maximum on the last day of incubation. The developmental pattern of heart rate in the shearwater was very similar to that reported previously for the brown noddy, a member of the order Charadriiformes but with the same pipping sequence. Developmental patterns of embryonic O2 pulse were also different between the two procellariiform seabirds. However, those of the shearwater and the noddy were similar. The sequence of access to atmospheric O2 during development and hatching may be an important factor determining the developmental patterns of embryonic heart rate and O2 pulse.

Active Breeding Burrows of the Wedge-tailed Shearwater in the Capricorn Group, Great Barrier Reef

Estimates of the breeding status of the Wedgetailed Shearwater Puffinus pacificus on the Capricorn Group of islands in the southern Great Barrier Reef indicate that the size of the breeding population is much lower than previously thought (500 000 pairs). For the 1989-90 season 43% and 56% of burrows, on Heron and Erskine Islands respectively, supported breeding birds. Most occupied burrows featured lined nesting chambers. Burrow lengths ranged from 0.1 m to 2.35 m with a mean of 0.91 m. There was no relationship between burrow length and breeding activity.

Hatching and the Establishment of Thermoregulation in the Wedge-Tailed Shearwater (Puffinus pacificus)

Late-incubation unpipped eggs, pipped eggs, and hatchlings of the wedge-tailed shearwater (Puffinus pacificus) were exposed to constant ambient temperatures ($T_{a}'s$) between 28° and 38°C (eggs) or 15° and 43°C (hatchlings). Below 36° C (incubation temperature for shearwater eggs), oxygen consumption ($\dot{V}O_{2}$) and body temperature ($T_{b}$) of embryos varied directly with $T_{a}$, even with individuals in eggs with well-developed pip holes. Thus, shearwaters appear unable to initiate and sustain any effective cold-induced thermogenesis before hatching, even though access to oxygen appears to improve substantially during pipping. In contrast, hatchlings increased their $\dot{V}O_{2}$ by as much as 74% during cooling, with the maximum rate occurring at a $T_{a}$ of 25°C. The consequent increase in heat production served to maintain $T_{b}$ near 35°C at $T_{a}'s$ between 25° and 35° C, but hypothermia tended to develop below 25°C. Hatchlings increased pulmocutaneous evaporation at $T_{a}'s$ above 36...

A Solution to the Problem of Determining the Occupancy Status of Wedge-tailed ShearwaterPuffinus pacificusBurrows

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.