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We describe a new Procellaria petrel species from the late Pliocene of Taranaki, New Zealand. The new species is most similar morphologically to the White-Chinned Petrel (P. aequinoctialis), Spectacled Petrel (P. conspicillata) and the Westland Petrel (P. westlandica). Compared with those taxa, the new species has a deeper and shorter premaxilla, longer coracoid and shorter wings, while its legs are a similar size. Today, New Zealand is the centre of global diversity of the genus, with four breeding species. This is the first fossil species of Procellaria to be described from New Zealand, attesting to a reasonably long history of this genus in the region. [ABSTRACT FROM AUTHOR]

Competition for nest sites is relatively common amongst burrow-nesting Procellariiformes, especially on some sub-Antarctic islands where there is limited availability of good burrow-nesting habitat. Where space is limited, petrels may even successfully share a common burrow entrance or nest chamber and burrow densities can reach >7000 burrows/ha. Interspecies burrow competition and chick evictions generally occur as a result of an overlap in breeding seasons, yet there are few documented records of this behaviour and even within study colonies many evictions are unconfirmed or probably go undetected. Here we report on interactions among three burrow-nesting petrels (White-chinned Petrels Procellaria aequinoctialis, Grey Petrels P. cinerea and Great-winged Petrels Pterodroma macroptera) at Marion Island which we observed through regular nest checks with a burrowscope and using infra-red video cameras inside burrow chambers. Despite relatively low petrel densities, White-chinned Petrels were responsible for 17% (8/46) of the Great-winged Petrel chick mortalities over the five breeding seasons (3% of the breeding attempts), but two were also recorded feeding Great-winged Petrel chicks. A pair of White-chinned Petrels evicted a Grey Petrel chick, but then had their own chick killed by Grey Petrels the following season, who went on to breed successfully in the same burrow. Feral Cats Felis catus were eradicated in 1991 and the greatly reduced petrel populations are slowly recovering, which could exacerbate competition for burrows on Marion. [ABSTRACT FROM AUTHOR]

We report the breeding success of four species of burrow-nesting petrels at sub-Antarctic Marion Island where house mice Mus musculus are the sole introduced mammal. Feral cats Felis catus were present on Marion for four decades from 1949, killing millions of seabirds and greatly reducing petrel populations. Cats were eradicated by 1991, but petrel populations have shown only marginal recoveries. We hypothesize that mice are suppressing their recovery through depredation of petrel eggs and chicks. Breeding success for winter breeders (grey petrels Procellaria cinerea (34±21%) and great-winged petrels Pterodroma macroptera (52±7%)) were lower than for summer breeders (blue petrels Halobaena caerulea (61±6%) and white-chinned petrels Procellaria aequinoctialis (59±6%)) and among winter breeders most chick fatalities were of small chicks up to 14 days old. We assessed the extent of mouse predation by monitoring the inside of 55 burrow chambers with video surveillance cameras (4024 film days from 2012–16) and recorded fatal attacks on grey (3/18 nests filmed, 17%) and great-winged petrel chicks (1/19, 5%). Our results show that burrow-nesting petrels are at risk from mouse predation, providing further motivation for the eradication of mice from Marion Island. [ABSTRACT FROM AUTHOR]

Threat status assessments provide a benchmark for identifying priorities for conservation and related research for special-status species. We review data about an endemic New Zealand seabird, the Westland Petrel Procellaria westlandica. and provide information to assist future threat assessment reviews. A range of threats have potential or have already contributed to reductions in population growth at a level that may exceed 10% over 10 years (ranked "High" or "High potential" threats). The realised (observed) threats include landslips and extreme climate events that degrade nesting habitat; bycatch mortality in commercial, recreational, and high-seas fisheries; attraction of fledglings to lights; and the potential encroachment of pigs Sits scrofa and dogs Canis familiaris into breeding areas. Low-ranked threats (which may contribute <10% to population reduction over 10 years) include habitat degradation by browsing introduced mammals and land development; death of individuals by striking wires or buildings; disturbance at colonies; the petrels' consumption of fisheries waste and plastics; human harvest; and naturally occurring mortality such as predation by native species or entrapment in tree branches and vines. Population size estimation, demographic modelling, and trend information indicate that the population is small (~2800 breeding pairs), with very low productivity and therefore potential vulnerability to stochastic events. Recent surveys show that the area of breeding habitat occupied by the birds is only about 0.16 km². Storm events in 2014 severely reduced habitat quality, destroyed large parts of some colonies, and increased the likelihood of further erosion and landslip for at least 75% of the global breeding population. Storm impacts at other colonies have not yet been assessed. In light of this information, we recommend immediate review of the threat status of the species and initiation of mitigation to reduce the severity of threats. The information available indicates that a relisting to IUCN Endangered status may be warranted, and that the Agreement on the Conservation of Albatrosses and Petrels threat assessments should be revised to include two high-level potential threats: pig predation and dog predation. [ABSTRACT FROM AUTHOR]

The white-chinned petrel Procellaria aequinoctialis is one of the most frequently observed seabird species captured in fisheries bycatch, yet some populations remain virtually unstudied. The size of the breeding population on the sub-Antarctic Auckland Islands, New Zealand, is unknown. Disappointment Island is thought to be the main white-chinned petrel breeding site in the Auckland Islands, and maybe also in the New Zealand region, and has never had introduced mammalian predators. We estimated the white-chinned petrel breeding population size taking into account the detection probability of burrows via distance sampling and the burrow occupancy rate. Eighty line transects were distributed over the island, with a total line length of 1600 m. Burrows were patchily distributed and most abundant in dense megaherb communities. White-chinned petrel burrow density $$ \hat{D } $$ was 654 burrows/ha (95 % CI 528-809 burrows/ha), with burrow detection probability $$ \hat{p} $$ varying among vegetation communities from 0.28 ± 0.02 to 0.43 ± 0.02 (±SE). Mean burrow occupancy was 0.73 ± 0.03. We document an estimated total of 155,500 (125,600-192,500) breeding pairs of white-chinned petrels on Disappointment Island during mid incubation in early January 2015. The relatively high occupancy and density of burrows suggest that Disappointment Island is a key breeding site for white-chinned petrels. [ABSTRACT FROM AUTHOR]

Both foreign and domestic pelagic longline fishing vessels operate in South Africa’s Exclusive Economic Zone and adjacent international waters where they kill hundreds of seabirds each year as bycatch. To update assessments of the impact of the pelagic longline fishery on seabirds off South Africa, information on necropsied seabirds and national fisheries observer bycatch records were summarised for 2006–2013. Foreign-flagged (Asian) vessels had 100% observer coverage throughout the study period, whereas only 6% of the fishing effort by South African-flagged vessels was observed (with no coverage in 2011–2013). Vessels with observers caught seabirds at a rate of 0.132 birds per 1 000 hooks, resulting in an estimated mortality of 2 851 individuals (356 per year) comprising 14 species. Extrapolation of the observed fishing sets to the unobserved fishing sets by the South African domestic longline fleet suggested that approximately 750 additional birds were likely killed during the study period, therefore a combined 450 birds were killed per year. White-chinned petrelProcellaria aequinoctialiswas the most frequently killed species (66%), followed by ‘shy-type’ albatrossesThalassarche cauta/steadi(21%), black-browed albatrossT. melanophris(7%), Indian yellow-nosed albatrossT. carteri(3%), and Cape gannetMorus capensis(2%). The seabird bycatch rates were lower than in 1998–2005. Nationality of the vessel, time of line-setting, moon phase, year, season, fishing area, and seabird bycatch mitigation measures all influenced seabird mortality. Concurrent with 100% observer coverage, significant reductions in the seabird bycatch rate occurred in the Asian fleet in the latter years of the study, and these rates now approximate the national target (0.05 birds per 1 000 hooks). However, seabird bycatch rates remained high in the South African fleet, where no observers were deployed during 2011–2013, highlighting the need for independent observer programmes in fisheries—a matter of global interest. Suggestions are made as to how seabird bycatch by pelagic longline fisheries off South Africa may be further reduced. [ABSTRACT FROM AUTHOR]

Intrinsic population growth rate ( rmax) is an important parameter for many ecological applications, such as population risk assessment and harvest management. However, rmax can be a difficult parameter to estimate, particularly for long-lived species, for which appropriate life table data or abundance time series are typically not obtainable. We describe a method for improving estimates of rmax for long-lived species by integrating life-history theory (allometric models) and population-specific demographic data (life table models). Broad allometric relationships, such as those between life history traits and body size, have long been recognized by ecologists. These relationships are useful for deriving theoretical expectations for rmax, but rmax for real populations may vary from simple allometric estimators for 'archetypical' species of a given taxa or body mass. Meanwhile, life table approaches can provide population-specific estimates of rmax from empirical data, but these may have poor precision from imprecise and missing vital rate parameter estimates. Our method borrows strength from both approaches to provide estimates that are consistent with both life-history theory and population-specific empirical data, and are likely to be more robust than estimates provided by either method alone. Our method uses an allometric constant: the product of rmax and the associated generation time for a stable-age population growing at this rate. We conducted a meta-analysis to estimate the mean and variance of this allometric constant across well-studied populations from three vertebrate taxa (birds, mammals, and elasmobranchs) and found that the mean was approximately 1.0 for each taxon. We used these as informative Bayesian priors that determine how much to 'shrink' imprecise vital rate estimates for a data-limited population toward the allometric expectation. The approach ultimately provides estimates of rmax (and other vital rates) that reflect a balance of information from the individual studied population, theoretical expectation, and meta-analysis of other populations. We applied the method specifically to an archetypical petrel (representing the genus Procellaria ) and to white sharks ( Carcharodon carcharias) in the context of estimating sustainable fishery bycatch limits. [ABSTRACT FROM AUTHOR]

The use of long-term ecological datasets to explore the importance of the effects of environmental variability on higher predator populations has been focused mainly on high-latitude areas. We modeled the population dynamics of the Westland Petrel ( Procellaria westlandica), which spends its time mostly in subtropical waters during both breeding and the interbreeding migration across the Pacific Ocean. We found that the population has slowly increased since the early 1970s, a result of high adult survival, high fecundity (0.6 of all eggs laid survived to fledge) and moderate mean age at first return to the colony (7.7 yr; a recruitment age typical for this genus), strong recruitment rate of juveniles, and negligible emigration. The modeled population trends were supported by similar rates of increase in nest occupancy since 2001 and nest density since 2007. Annual adult survival for breeders was the same for both sexes (0.954, 95% CI: 0.918-0.975) and constant across years. However, nonbreeders had lower survival rates than breeders, and, among nonbreeders, males tended to survive better (0.926, 95% CI: 0.917-0.934) than females (0.917, 95% CI: 0.900-0.931). Breeders transitioned to the nonbreeding state at a rate of 0.232 and nonbreeders to the breeding state at a rate of 0.295. Sea-surface temperature anomalies had a negative effect on adult survival during the breeding period and a positive effect on survival outside the breeding season. Local marine productivity as measured by fishery catches was strongly correlated with adult survival: Years with a greater fish catch were also years of higher adult survival. Despite many threats operating throughout the breeding and foraging range of Westland Petrels, it appears that marine environmental change is a strongly influential factor for the species, with uncertainty in population growth due to predicted increases in sea-surface temperature in the future. [ABSTRACT FROM AUTHOR]

ABSTRACT The large midden site of Offing 2 (southern Chile) has yielded a series of human occupations dating back to 4200-2500 bp. From a very large collection of bird specimens, we sampled over 45 000 bird bones from four taxa ( Diomedea sp., Procellaria sp., Phalacrocorax sp. and Sterna hirundinacea). The distributions of skeletal parts do not contradict the bone density and functional anatomy hypotheses for cormorants and terns, but the observed data for albatross and petrel are less convincing. The presence of most or all elements (except for the terns) indicates that the birds were brought back to the site as complete carcasses. The deficit of some of the long wing bones observed for albatross and petrel is remarkable and may indicate a particular removal for later use as raw material for tools or trade goods. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Satellite transmitters were attached to eight adult spectacled petrels Procellaria conspicillata Gould captured during the early incubation period at their breeding grounds on Inaccessible Island, one of the Tristan da Cunha Islands in the central South Atlantic Ocean. Data on their at-sea distribution was obtained for up to six months. All birds remained within the South Atlantic from 24–44°S, with most between 25 and 40°S. Breeding birds mainly foraged in oceanic waters, but failed breeders or non-breeders concentrated their foraging activity over the Rio Grande Rise and the Walvis Ridge and along the shelf break off the east coast of South America. Little foraging occurred along the Benguela shelf break off southern Africa. Non-breeders favoured relatively warm water with low chlorophyll concentrations, reducing the risk of bycatch in fisheries. Tracked birds spent 16% of their time in areas with high levels of tuna longline fishing activity, with overlap greater for non-breeding birds (22%) than breeding birds (3%). Birds in this study foraged in shallower waters along the continental shelf edge off South America than spectacled petrels tracked in this area in winter, potentially increasing their risk of exposure to demersal longline fisheries in this area in summer. [ABSTRACT FROM AUTHOR]

Concentrations of copper (Cu), zinc (Zn), cadmium (Cd), lead (Pb), mercury (Hg), and selenium (Se) were determined in blood and feathers of spectacled ( Procellaria conspicillata) and white-chinned ( Procellaria aequinoctialis) petrels, species that are phylogenetically related, but with distinct ecological niches. In winter, they feed on similar foods, indicated by an overlapping range of whole-blood stable isotopes values (δ15N; δ13C). No relation was found between blood metal concentration and stable isotope values. In spectacled petrels, metal concentrations appeared lower in blood (Cu = 0.79-20.77 µg/g; Zn = 10.95-28.02 µg/g; Cd = 1.73-10.11 µg/g; Pb = 5.02-26.03 µg/g; Hg = 0.84-9.86 µg/g) than in feathers (Cu = 1.05-21.57 µg/g; Zn = 45.30-81.49 µg/g; Cd = 3.76-10.44 µg/g; Pb = 16.53-59.00 µg/g; Hg = 4.24-24.03 µg/g). In white-chinned petrels, metal concentrations also appeared lower in blood (Cu = 0.62-10.4 µg/g; Zn = 10.73-24.69 µg/g; Cd = 2.00-6.31 µg/g; Pb = 5.72-24.03 µg/g) than in feathers (Cu = 2.68-23.92 µg/g; Zn = 48.96-93.54 µg/g; Cd = 5.72-24.03 µg/g; Pb = 18.62-55.51 µg/g), except for Hg (blood = 0.20-15.82 µg/g; feathers = 0.19-8.91 µg/g). Selenium (0.24-14.18 µg/g) and Hg (0.22-1.44 µg/g) concentrations showed a positive correlation in growing feathers of spectacled petrels. Blood and feather Hg levels were higher in spectacled petrels while feathers Cu and Zn concentrations were greater in white-chinned petrels. Juvenile white-chinned petrels exhibited greater blood Hg concentrations than adults. In the south Atlantic Ocean, discards from commercial fishing operations consumed by spectacled petrels year-round and by white-chinned petrels during the wintering period have elevated Hg concentrations. Because Hg toxicity is associated with behavioral and reproductive changes in birds, it could potentially have impacts on breeding of these seabirds, as both species are listed as threatened by extinction. Environ Toxicol Chem 2013;32:1641-1648. © 2013 SETAC [ABSTRACT FROM AUTHOR]

Rapid classification of a study subject's gender is critical for many ecological, behavioral, and conservation projects. We evaluated sexual-size dimorphism of adult Westland Petrels (Procellaria westlandica), a large nocturnal colony-nesting seabird, using linear discriminant function analysis and compared our results to birds classified using standard DNA gender identification techniques. The results revealed a strong pattern of sexual dimorphism (Wilks' Lambda = 0.43, F7.29 = 5.6, P < 0.001/ in the standard discriminant function analysis despite an unbalanced sex ratio in our sample of adults captured at the breeding colony. Minimum bill depth and head length, of the seven morphometric characters we measured, successfully assigned the correct gender to 95% of all individuals sampled (n = 37). We provide a canonical classification function of morphological traits that may be used in the field to rapidly differentiate adult females and males of this rare petrel species. [ABSTRACT FROM AUTHOR]

This exploratory study tested the hypothesis that petrels (Aves: Procellaridae) actively plough the soil of their entire breeding colonies, as implied by their well-known burrowing capabilities but contra-indicated by widespread horizonation in colony soil. Two profiles to lithic contact were excavated within a forested Westland petrel (Procellaria westlandica) colony; one, a ridgeline control without nearby petrel burrows, and the other from a steep slope among petrel burrows. On the ridgeline, 137Cs activities (estimated per volume) steadily decreased with depth as expected. At the burrowed site, a subsurface maximum at 12-16 cm depth indicated a post-1963 burrowing or landslip event. Both 210Pb profiles were successfully modelled (r 2 c. 0.9) using a simple first-order model usually applicable only to undisturbed soils. In this model, mixing is accounted for by radioactive decay and first-order, mm-scale biodiffusion. The results therefore indicated that soil mixing was not dominated by petrel burrowing; rather, petrels confine their burrowing activities to maintenance of their burrows as semi-permanent (decades to centuries) structures. However, further sampling is recommended to confirm this view. [ABSTRACT FROM AUTHOR]

Background: Determining the foraging movements of pelagic seabirds is fundamental for their conservation. However, the vulnerability and elusive lifestyles of these animals have made them notoriously difficult to study. Recent developments in satellite telemetry have enabled tracking of smaller seabirds during foraging excursions. Methodology/Principal Findings: Here, we report the first successful precision tracking of a c. 700 g seabird, the vulnerable Black Petrel, Procellaria parkinsoni, foraging at sea during the breeding season, using miniature GPS-logging technology. Employing a combination of high-resolution fixes and low-power duty-cycles, we present data from nine individual foraging excursions tracked during the chick-rearing period in February 2006. Conclusions/Significance: We provide a snapshot of the species' foraging range and behaviour in relation to detailed underlying bathymetry off the coast of New Zealand, finding a significant relationship between foraging movements and regions of the shelf-break. We also highlight the potential of more sophisticated analyses to identify behavioural phenomena from position data alone. [ABSTRACT FROM AUTHOR]

Abstract: The genus Procellaria traditionally consists of four species, two restricted to New Zealand and two widespread in the Southern Ocean. All four are threatened because of incidental mortality on longlines and other fishing gear. The White-chinned Petrel P. aequinoctialis is the seabird killed in largest numbers by fisheries in the Southern Ocean. A spectacled form recently has been elevated to species status, Spectacled Petrel P. conspicillata, based on differences in morphometrics, vocalisations and breeding phenology. Cytochrome b sequences support species status for the Spectacled Petrel and show that the White-chinned Petrel has two regional populations, one around New Zealand and one throughout the South Atlantic and Indian Oceans. White-chinned and Spectacled Petrels segregated approximately 0.90 million years ago by allopatric fragmentation, and the two populations within White-chinned Petrels diverged approximately 0.35 million years ago. Climate changes and corresponding changes in ocean currents are most likely responsible for these patterns. [Copyright &y& Elsevier]

White-chinned petrels Procellaria aequinoctialis and grey petrels Procellaria cinerea are among the most frequently killed seabird species by accidental bycatch, and both species have received strong conservation concern. Data on population size are required to evaluate the impact of bycatch and to establish management plans. We estimated the population size of both species at Kerguelen, Southern Indian Ocean, from 2004 to 2006 by explicitly taking into account detection probability of burrows using distance sampling and burrow occupancy. A total of 31 line-transects were distributed across the eastern part of Kerguelen, representing a total length of 566 km. Detectability was low (from 0.19 to 0.54 for white-chinned petrels, 0.58 for grey petrels). Burrow densities varied from 1.37±0.67 to 25.77±5.23 burrows ha−1 for white-chinned petrels and was 2.78±0.79 burrows ha−1 for grey petrels. For white-chinned petrels, these densities were extrapolated to the entire surface area of vegetation and there were 234 000 (186 000–297 000) active burrows on Kerguelen. For grey petrels, the number of active burrows for the eastern part of Kerguelen was 3400 (1900–5600). Based on these estimates, the potential biological removal method suggests that the additional mortality on birds caused by the fisheries operating around Kerguelen can be considered a serious threat for the species at least at the regional scale of the Southern Indian Ocean, especially for grey petrels. [ABSTRACT FROM AUTHOR]

The article focuses on Tristan da Cunha archipelago and Gough Island, which are regarded as separate Endemic Bird Areas (EBAs) because of their unique landbirds. It is stated that they are the only cool-temperate oceanic islands in the South Atlantic that are important breeding sites for seabirds. The islands are home to seven landbird species and they share many of the same seabirds. It is noted that the Spectacled Petrel Procellaria conspicillata is found only on Inaccessible Island, while all Tristan Albatrosses Diomedea dabbenena and Atlantic Petrels Pterodroma incerta breed on Gough.

1. Fisheries can affect non-target species through bycatch, and climate change may act simultaneously on their population dynamics. Estimating the relative impact of fisheries and climate on non-target species remains a challenge for many populations because the spatio-temporal distribution of individuals remains poorly known and available demographic information is incomplete. 2. We used population survey data, capture–mark–recapture methods, population modelling and the demographic invariant method to investigate the effects of climate and fisheries on the demography of a predator species affected by bycatch. These complementary approaches were used to help account for different sources of uncertainty. 3. The white-chinned petrel Procellaria aequinoctialis is the commonest seabird species killed by longline fisheries in the Southern Ocean. Petrel breeding success was positively related to the fishing effort for Patagonian toothfish Dissosticus eleginoides. El Niño events negatively affected adult survival with a time lag of 3 years. Fishing efforts for toothfish and hake ( Merluccius spp.) were negatively related to petrel recruitment, suggesting that fisheries-induced mortality strongly impacted younger age classes. Lambda estimated from matrix population models was below replacement (0·964 ± 0·026), and the number of breeding pairs declined by ≈ 37% in 21 years. This decline was probably caused by low survival of both young age classes and adults. 4. The Crozet archipelago, Southern Indian Ocean, population size was estimated at ≈ 170 000 individuals in the early 1980s, and would be severely affected by any additional source of mortality that approached 8000 individuals per year. The number of petrels killed by the toothfish fishery alone exceeded this threshold during the late 1990s and early 2000s, but has declined well below this since 2003. 5. Synthesis and applications. Complementary approaches suggest that both longline fishery bycatch and climate have a significant impact on the size of the Southern Ocean white-chinned petrel population. Stopping or reversing climate change will be a very slow process, and may be impossible. Therefore, we recommend a reduction in bycatch to help the populations recover. Further information on the status of individuals caught in longlines is required to understand the demographic processes involved. [ABSTRACT FROM AUTHOR]

I compare plastic ingested by five species of seabirds sampled in the 1980s and again in 1999–2006. The numbers of ingested plastic particles have not changed significantly, but the proportion of virgin pellets has decreased 44–79% in all five species: great shearwater Puffinus gravis, white-chinned petrel Procellaria aequinoctialis, broad-billed prion Pachyptila vittata, white-faced storm petrel Pelagodroma marina and white-bellied storm petrel Fregetta grallaria. The populations sampled range widely in the South Atlantic and western Indian Oceans. The most marked reduction occurred in great shearwaters, where the average number of pellets per bird decreased from 10.5 to 1.6. This species migrates between the South and North Atlantic each year. Similar decreases in virgin pellets have been recorded in short-tailed shearwaters Puffinus tenuirostris in the Pacific Ocean and northern fulmars Fulmarus glacialis in the North Sea. More data are needed on the relationship between plastic loads in seabirds and the density of plastic at sea in their foraging areas, but the consistent decrease in pellets in birds suggests there has been a global change in the composition of small plastic debris at sea over the last two decades. [Copyright &y& Elsevier]

We studied the diet of feral cats ( Felis catus) on New Island, Falkland Islands, through the analysis of 373 scats collected during the austral summers of 2004/2005 and 2005/2006. The most frequent prey were three introduced mammals (house mice Mus musculus, ship rats Rattus rattus and rabbits Sylvilagus sp.) and the thin-billed prion Pachyptila belcheri (each season present on ca. 21% of the analysed scats). These represent the first systematic data on feral cat diet for the Falklands. A simple bioenergetics model suggests that cats could be eating in the region of 1,500–11,000 prions per season, representing <1% of the local adult and subadult population. Predation on other seabirds nesting on New Island (several penguin species, albatrosses and cormorants) was unimportant, with the possible exception of white-chinned petrels Procellaria aequinoctialis, which nest locally in very small numbers. For each prion eaten, cats were estimated to have killed 1.1–1.9 ship rats during the summer season, and probably more in autumn and winter. Knowing that ship rats are prion predators, it is conceivable that, on the whole, cats are having a positive impact on the prion population, a scenario predicted by general theoretical models. Thus, considering the available information, we would not recommend the implementation of any eradication programme on New Island that would target cats in isolation. Nevertheless, it would be prudent to consider some local action targeting cats and rats around the small New Island white-chinned petrel colony. [ABSTRACT FROM AUTHOR]

The report by Titian Ramsay Peale on birds encountered during the Wilkes Expedition was withdrawn for inaccuracy when few copies had been distributed, and re-written by John Cassin. A survey of the accounts of the petrels shows that this was not an improvement. Two important type localities for Procellaria brevipes and Thalassidroma lineata are probably wrong, and could be exchanged. [ABSTRACT FROM AUTHOR]

The diet of white-chinned petrels Procellaria aequinoctialis breeding at the Crozet Archipelago (southern Indian Ocean) was studied using two complementary methods: lipid analysis of stomach oils as trophic markers together with the conventional dietary approach (i.e., stomach content analysis). Objectives were (1) to investigate the adult diet when they feed for themselves by analyzing stomach oil lipids, and (2) to compare the lipid signature of chick and adult oils. Stomach oils mainly consisted of triacylglycerols (TAG), diacylglycerol-ethers (DAGE) and wax esters (WE) (66, 14 and 11%, respectively). The dietary origin of TAG and WE was evaluated by linear discriminant analyses with fatty acid and fatty alcohol fractions. Analyses evidenced that stomach oils did not originate from Antarctic krill, but instead from myctophid fish, thus demonstrating the importance of mesopelagic fish in the nutrition of adult petrels. This result was consistent with the identification of digested remains of myctophids recovered from adult stomach contents after long foraging trips. Large amounts of a rare lipid class, DAGE (up to 76% of total lipids), were identified in two stomach oils, together with fresh remains of the squid Gonatus antarcticus (99% by mass), suggesting that DAGE could have the potential to be trophic markers of cephalopods. Moreover, six oils probably originated from Patagonian toothfish, thus confirming strong interactions between white-chinned petrels and fisheries. Comparison between chick and adult stomach oils indicated no major differences in their biochemical composition suggesting an identical dietary origin of oils, mainly myctophids. Both adult and chick oils can therefore be used to determine the feeding ecology of adult birds when they feed far away from their breeding grounds. Finally, food analysis of chick samples and adult samples collected after short and long trips indicated different foraging grounds during the two kinds of trips, and also between long trips performed in subtropical and Antarctic waters. [ABSTRACT FROM AUTHOR]

Abstract: The spectacled petrel Procellaria conspicillata is listed as critically endangered due to its small population size and ongoing mortality on long-lines. Spectacled petrels were counted in 2004, repeating a census made in 1999 at their sole breeding locality, Inaccessible Island. The 2004 survey took place earlier in the breeding season than the previous count, allowing for more robust estimates of burrow occupancy. During early incubation, birds responded to call playback at 69% of burrow entrances, but birds in at least 8% of burrows remained silent. Birds in shallow burrows were less likely to respond to playback than were those in deep burrows. Two repeat trials at 100 marked nests showed that at least 61% of apparently ‘unoccupied’ burrows were occupied on subsequent checks, resulting in an overall occupancy estimate of 91%. Occupancy was equally high in peripheral colonies. The apparent spatial extent of colonies increased slightly from 1999, and the estimate of total burrow numbers increased by 50%, from 5900 burrows in 1999 to 8900 in 2004. Validation surveys indicated that burrow numbers were underestimated (84±3%) to the same extent as that in 1999 (85±4%), and repeat checks of one colony where all nests were marked showed that even careful counts underestimated actual numbers of burrows by up to 10%. This suggests there are some 11–12,000 burrows, and assuming 90% occupancy, the adult population is likely to be at least 20,000 birds. The population has increased over the last five years, continuing the apparent recovery from a very small population size in the early 20th century. Despite this increase, demographic models indicate that the population remains at risk from relatively small increases in mortality, if mortality is determined primarily by fishing effort. Mitigation of long-line mortality remains the key conservation goal for this species. [Copyright &y& Elsevier]

The white-chinned petrel is a subantarctic seabird that requires urgent implementation of conservation measures for the species. At sea, adults suffer heavy mortality due to fisheries' practices. On land, introduced rats prey on chicks at several localities, and we test here if and how rats can be efficiently controlled. Since 1994, we have conducted an intensive rat-control program during each breeding season in a white-chinned petrel colony on Ile de la Possession (150 km2; Crozet archipelago, southern Indian Ocean), which had been monitored since 1986. On the same island, a control white-chinned petrel colony, where no poisoning occurred, was also monitored, and we assessed the seasonal variations of rat abundance. We compared three situations: high rat-poisoning, low rat-poisoning and control conditions without poisoning. Low-poisoning trials performed in our experimental colony between 1988 and 1991 did not lead to higher chick production than for the previous two control years. However, petrel-breeding success was significantly higher when intensive poisoning occurred (50%) than for the previous years (16%). The duration of our study (8 years before intensive poisoning, plus 8 years afterwards), combined with a comparison of petrel annual breeding success between our experimental and control colonies, allowed us to assess more effectively the impact of rats. Forty-one per cent of breeding failures occurring in non-poisoned areas were attributed to rats. We conclude that threatened insular bird populations can be conserved and restored in localities even where total rat eradication is not possible. However, only intensive and repeated (long-term) poisoning will control rats sufficiently. [ABSTRACT FROM AUTHOR]