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Aim: To assess the efficacy of marine reserves in Australia for shy albatross, using long‐term tracking data. Location: Albatross Island, Tasmania, and south Australian waters. Methods: We integrated a tracking dataset consisting of 111 individuals collected over 23 years and generated Brownian bridge kernel density estimations to identify important habitat. We quantified the overlap between the foraging distribution of early incubating adults and post‐fledgling juveniles with management boundaries and marine reserves. We compared the extent of coverage of albatross foraging areas by Marine Protection Areas (MPAs) relative to a randomly designed network of the same size to determine whether the spatial protection measures are likely to be effective. Results: Incubating adults consistently foraged in waters to the northwest of Tasmania while post‐fledglings occupied shelf waters around Tasmania and South Australia. We show that our sample of 99 incubating adults adequately represented the population but that our sample of 12 post‐fledgling birds was insufficient, thereby limiting the confidence in our results for this life stage. The Commonwealth Government has the majority of management responsibility for shy albatross at‐sea, containing 88% and 90% of the area occupied most intensively by adult and post‐fledgling shy albatross, respectively. Randomly designed reserve networks outperformed the current MPA network for both life stages, such that the mean protection by a random reserve system was 30% and 12% higher than the actual protection for adults and juveniles in Commonwealth waters. Main conclusions: Important foraging habitat of shy albatross from Albatross Island is mostly within Commonwealth‐managed waters. The current MPA network, the only spatial protection measure for shy albatross, provides less coverage for this species than a randomly placed network. An increase in the representation of productive shelf waters in MPA networks would benefit the conservation of shy albatross through reducing fisheries interactions and protecting habitat in these regions. [ABSTRACT FROM AUTHOR]

Gelatinous zooplankton are a large component of the animal biomass in all marine environments, but are considered to be uncommon in the diet of most marine top predators. However, the diets of key predator groups like seabirds have conventionally been assessed from stomach content analyses, which cannot detect most gelatinous prey. As marine top predators are used to identify changes in the overall species composition of marine ecosystems, such biases in dietary assessment may impact our detection of important ecosystem regime shifts. We investigated albatross diet using DNA metabarcoding of scats to assess the prevalence of gelatinous zooplankton consumption by two albatross species, one of which is used as an indicator species for ecosystem monitoring. Black-browed and Campbell albatross scats were collected from eight breeding colonies covering the circumpolar range of these birds over two consecutive breeding seasons. Fish was the main dietary item at most sites; however, cnidarian DNA, primarily from scyphozoan jellyfish, was present in 42% of samples overall and up to 80% of samples at some sites. Jellyfish was detected during all breeding stages and consumed by adults and chicks. Trawl fishery catches of jellyfish near the Falkland Islands indicate a similar frequency of jellyfish occurrence in albatross diets in years of high and low jellyfish availability, suggesting jellyfish consumption may be selective rather than opportunistic. Warmer oceans and overfishing of finfish are predicted to favour jellyfish population increases, and we demonstrate here that dietary DNA metabarcoding enables measurements of the contribution of gelatinous zooplankton to the diet of marine predators. [ABSTRACT FROM AUTHOR]

Conservation of marine species typically focuses on monitoring and mitigating demonstrated stressors where possible. Evidence is accumulating that some species will be negatively affected in the future by climate change and that reduction of existing stressors may not be sufficient to offset these impacts. Recent work suggests the shy albatross ( Thalassarche cauta ) will be adversely affected by projected changes in environmental conditions under plausible climate change scenarios. Furthermore, modelling shows that elimination of the principal present-day threat to albatrosses, fisheries bycatch, an achievable and critical priority, may not be sufficient to reverse projected population declines due to climate impacts, which cannot be directly eliminated. Here, a case study is presented in which a range of intervention options, in preparation for predicted climate change impacts, are identified and evaluated. A suite of 24 plausible climate adaptation options is first assessed using a semi-quantitative cost–benefit–risk tool, leading to a relative ranking of actions. Of these options, increasing chick survival via reduction of disease prevalence through control of vectors, was selected for field trials. Avian insecticide was applied to chicks’ mid-way through their development and the effect on subsequent survival was evaluated. Survival of treated chicks after six weeks was significantly higher (92.7%) than those in control areas (82.1%). This approach shows that options to enhance albatross populations exist and we argue that testing interventions prior to serious impacts can formalise institutional processes and allow refinement of actions that offer some chance of mitigating the impacts of climate change on iconic marine species. [ABSTRACT FROM AUTHOR]

The impacts of climate change on marine species are often compounded by other stressors that make direct attribution and prediction difficult. Shy albatrosses (Thalassarche cauta) breeding on Albatross Island, Tasmania, show an unusually restricted foraging range, allowing easier discrimination between the influence of non-climate stressors (fisheries bycatch) and environmental variation. Local environmental conditions (rainfall, air temperature, and sea-surface height, an indicator of upwelling) during the vulnerable chick-rearing stage, have been correlated with breeding success of shy albatrosses. We use an age-, stage- and sex-structured population model to explore potential relationships between local environmental factors and albatross breeding success while accounting for fisheries bycatch by trawl and longline fisheries. The model uses time-series of observed breeding population counts, breeding success, adult and juvenile survival rates and a bycatch mortality observation for trawl fishing to estimate fisheries catchability, environmental influence, natural mortality rate, density dependence, and productivity. Observed at-sea distributions for adult and juvenile birds were coupled with reported fishing effort to estimate vulnerability to incidental bycatch. The inclusion of rainfall, temperature and sea-surface height as explanatory variables for annual chick mortality rate was statistically significant. Global climate models predict little change in future local average rainfall, however, increases are forecast in both temperatures and upwelling, which are predicted to have detrimental and beneficial effects, respectively, on breeding success. The model shows that mitigation of at least 50% of present bycatch is required to offset losses due to future temperature changes, even if upwelling increases substantially. Our results highlight the benefits of using an integrated modeling approach, which uses available demographic as well as environmental data within a single estimation framework, to provide future predictions. Such predictions inform the development of management options in the face of climate change. [ABSTRACT FROM AUTHOR]

Climate adaptation is an emerging practice in biodiversity conservation, but little is known about the scope, scale, and effectiveness of implemented actions. Here, we review and synthesize published reports of climate adaptation interventions for iconic fauna. We present a systematic map of peer‐reviewed literature databases (Web of Science and Scopus); however, only nine climate adaptation actions targeting iconic fauna were returned. In the grey and informal literature, there were many instances of practical intervention within our scope, that were not uncovered during traditional systematic search methods. The richness of actions reported in commercial news, government and non‐government organization media outlets and other online sources vastly outweighs the limited studies that have been robustly evaluated and reported in the scientific literature. From our investigation of this emerging field of conservation practice, we draw insights and pen a series of recommendations for the field moving forward. Key recommendations for future adaptation interventions include: the sharing and publishing of climate‐related conservation interventions, the use of standardized metrics for reporting outcomes, the implementation of experimental controls for any actions undertaken, and reporting and evaluation of both failures and successes. [ABSTRACT FROM AUTHOR]

The eradication of invasive species from islands yields significant conservation returns. However, novel challenges continue to arise as projects expand in their scope, complexity and scale. Prey‐loss and secondary poisoning were historically considered to have limited impact on native top‐order predators when planning eradications, but this has rarely been tested quantitatively.We used a 10‐year timeseries of Brown Skua Stercorarius antarcticus lonnbergi breeding surveys and isotopic dietary analysis on Macquarie Island to investigate how prey‐loss and secondary poisoning deaths resulting from the eradication of an abundant invasive prey species, European rabbits Oryctolagus cuniculus, affected a top‐order predator.Skua nest density declined from 7.14 nests/km2 (95% CI: 6.01–8.27) in the presence of rabbits (pre‐eradication) to 3.73 nests/km2 (95% CI: 2.96–4.51) in the first 3 years after the eradication of rabbits, before showing signs of recovery in the 4 years thereafter. However, breeding success dropped from 1.01 chicks/nest (95% CI: 0.76–1.26) to as low as 0.38 chicks/nest (95% CI: 0.23–0.53) with little evidence of recovery.Secondary poisoning affected a greater number of skuas than anticipated prior to the eradication, including skuas nesting in areas where rabbits were not typically hunted as prey. We highlight that invasive prey often replace native prey in the diet of native predators rather than provide an additional source of food, and rapid eradication of non‐native prey can have long‐term impacts for predators, particularly when recovery of native prey is slow.Synthesis and applications. Monitoring programmes that complement large‐scale eradication projects and address (a) trophic‐driven declines in predator populations and (b) population‐level impacts of secondary poisoning are integral to ensuring bottom‐up effects of eradications are anticipated and adequately quantified. If prey deficits caused by eradication of invasive prey are expected to be severe but short‐lived, supplementary feeding programmes may buffer against increased predation pressure on native prey and reduced breeding success of native predators. Alternatively, if the rapid recovery of native prey is not expected to occur naturally, breeding programmes and translocation of native prey prior to assist recovery of native predators should be considered to support ecosystem restoration. [ABSTRACT FROM AUTHOR]

Quantifying the intra‐ and interindividual variation that exists within a population can provide meaningful insights into a population's vulnerability and response to rapid environmental change. We characterise the foraging behaviour of 308 trips taken by 96 shy albatross (Thalassarche cauta) from Albatross Island across seven consecutive years. At a population level, incubating shy albatross exploited a consistent area within ca. 500 km radius of their breeding colony. During half of the trips, individuals utilised the closest shelf break to the west of the colony, where upwelling events have been reported. The other half of the trips were exclusively within the neritic zone, utilising a variety of locations within the Bass Strait. Furthermore, we found evidence of individual consistency to geographic locations, with subsequent trips by an individual more similar than random trips from all individuals in our data, both within and between years (G‐test, p <.05). Between‐individual variation in foraging behaviour was not meaningfully explained by age (linear regression, p >.05) or sex (t‐test, p >.05) for any metric, suggesting that other intrinsic individual factors are accounting for between‐individual variation in foraging trips. A localised foraging distribution is unusual for albatross, which, combined with high variation in space use between individuals demonstrated here, suggests that this species is accessing adequate resources near the colony. Overall, these findings suggest that incubating shy albatross from Albatross Island exhibit tendencies of a generalist population comprised of uniquely specialised individuals. These results suggest that this species is operating below its biological capacity in this fast‐warming area and provide a baseline from which to assess future change. [ABSTRACT FROM AUTHOR]

Maximising survey efficiency can help reduce the tradeoff between spending limited conservation resources on identifying population changes and responding to those changes through management. Burrow‐nesting seabirds are particularly challenging to survey because nests cannot be counted directly. We evaluated a stratified random survey design for generating unbiased population estimates simultaneously for four petrel species nesting on Macquarie Island, Australia, where the survey cue, burrow entrances, is similar for all species. We also compared the use of design‐based and model‐based analyses for minimising uncertainty in estimates. We recorded 2845 Antarctic prion burrows, 306 white‐headed petrel burrows and two blue petrel burrows while distance‐sampling along 154 km of transects. For blue petrels and grey petrels, we completed nocturnal searches along a further 71 km and searched 249 km of tracks during follow‐up ground searches. We failed to generate unbiased population estimates for two rare and localised species, blue and grey petrels, from our stratified random survey. Only for the most widespread and abundant species, Antarctic prion, did the estimate have reasonable power to detect a rapid population change. Model‐based analyses of the stratified random survey data did not improve upon traditional design‐based analyses in terms of uncertainty in population estimates, but they did provide useful spatial representation of current populations. Models that used the targeted survey data did not reflect current population sizes and distributions of the two rare and localised species. We found that when species ecologies, distributions and abundances vary, a multi‐method approach to surveys is needed. Species with low abundance that occur patchily across large islands are likely to be best estimated using targeted surveys, whereas widespread and abundant species can be accurately and precisely estimated from randomised surveys using informative model‐based analyses. [ABSTRACT FROM AUTHOR]

Aim Introduced predators are a global driver of species decline, but their impact on highly mobile species is poorly understood. We report the severe impact of a previously undocumented introduced predator on the endangered, migratory swift parrot ( Lathamus discolor). Sugar gliders ( Petaurus breviceps), a supposedly benign introduced species, were detected acting as a major opportunistic predator of cavity-nesting birds. We assessed the intensity and geographical extent of sugar glider predation and investigated whether habitat loss exacerbated predation risk to swift parrots. Location Tasmania, Australia. Methods We monitored nests of swift parrots for 3 years with motion-activated cameras. We used bioclimatic modelling to predict the potential distribution of introduced sugar gliders across the study area and assessed the predation risk to swift parrots and other threatened birds in the region using nest-survival analysis. Results Daily survival of nests in areas where sugar gliders occurred was mean 0.97, which equated to a true likelihood of 0.17 for a nest to survive the 60-day nesting period. No nests failed on an offshore island where sugar gliders were shown to be absent. Most cases (83.3%) of glider predation resulted in the death of the adult female parrot. On the Tasmanian mainland, there was a positive relationship between nest survival and increasing mature forest cover at the landscape scale. Main conclusions Predation risk varied dramatically across the breeding range of swift parrots, depending on the presence of sugar gliders. Offshore islands are an important refuge for swift parrots because sugar gliders are absent. However, islands are vulnerable, and our bioclimatic model shows that they are bioclimatically suitable for sugar gliders. Synergistic interactions between predation and habitat loss combine with low breeding-site philopatry to expose swift parrots to dramatic variation in predation risk depending on nesting location. [ABSTRACT FROM AUTHOR]

Interspecific introgression can occur between species that evolve rapidly within an adaptive radiation. Pachyptila petrels differ in bill size and are characterised by incomplete reproductive isolation, leading to interspecific gene flow. Salvin's prion (Pachyptila salvini), whose bill width is intermediate between broad-billed (P. vittata) and Antarctic (P. desolata) prions, evolved through homoploid hybrid speciation. MacGillivray's prion (P. macgillivrayi), known from a single population on St Paul (Indian Ocean), has a bill width intermediate between salvini and vittata and could also be the product of interspecies introgression or hybrid speciation. Recently, another prion population phenotypically similar to macgillivrayi was discovered on Gough (Atlantic Ocean), where it breeds 3 months later than vittata. The similarity in bill width between the medium-billed birds on Gough and macgillivrayi suggest that they could be closely related. In this study, we used genetic and morphological data to infer the phylogenetic position and evolutionary history of P. macgillivrayi and the Gough medium-billed prion relative other Pachyptila taxa, to determine whether species with medium bill widths evolved through common ancestry or convergence. We found that Gough medium-billed prions belong to the same evolutionary lineage as macgillivrayi, representing a new population of MacGillivray's prion that originated through a colonisation event from St Paul. We show that macgillivrayi's medium bill width evolved through divergence (genetic drift) and independently from that of salvini, which evolved through hybridisation (gene flow). This represents the independent convergence towards a similarly medium-billed phenotype. The newly discovered MacGillivray's prion population on Gough is of utmost conservation relevance, as the relict macgillivrayi population in the Indian Ocean is very small. [ABSTRACT FROM AUTHOR]

Albatrosses are among the world's most endangered seabirds. Threats during the nonbreeding period have major impacts on their population dynamics, but for most species, detailed information on distribution and ecology remains essentially unknown. We used stable isotope values (δ13C and δ15N) in feathers to infer and compare the moulting (nonbreeding) habitats of 35 populations that include all the 20 species and subspecies (444 individuals) of albatrosses breeding within the Southern Ocean and in fringing subtropical waters. Isotopic values together with a review of available information show that the 20 albatrosses can be categorized into three groups depending on their favoured moulting grounds: 12 (60%) taxa forage primarily in warm neritic waters, six (30%) in northern oceanic waters and two (10%) in oceanic waters of the Southern Ocean. Stable isotopes indicate that habitat preferences during the nonbreeding period vary much less among different breeding populations in some species (wandering, Salvin's, grey-headed and light-mantled sooty albatrosses), than others (black-browed, Indian yellow-nosed and sooty albatrosses). The major finding of our isotopic investigation is that the great majority of albatrosses spend the nonbreeding period outside the Southern Ocean, with only three species (and in the sooty albatross, just one of the breeding populations) favouring oceanic subantarctic waters at that time. Hence, the study highlights the overwhelming importance of subtropical waters for albatrosses, where the birds are known to interact with human activities and are more likely to be negatively affected by the diverse range of fisheries operating in both neritic and oceanic waters. [ABSTRACT FROM AUTHOR]

Gentoo penguins (Pygoscelis papua) have a widespread breeding distribution across the sub-Antarctic and Antarctic. Population trends vary across their range, with increases recorded in the Antarctic and Atlantic sectors of the Southern Ocean, while other sub-Antarctic populations are decreasing. Macquarie Island is the only breeding site for gentoo penguins in the Pacific sector of the Southern Ocean and one of just two breeding sites within Australian territories. Eight island-wide censuses were undertaken between 1984 and 2017 to estimate the number of breeding pairs, with a follow-up chick census conducted in four years to calculate breeding success. The most recent census in 2017 recorded the fewest breeding pairs since counts began, with 2527 ± 66 gentoo pairs island wide. However, breeding success was the highest recorded at 0.99 chicks per nest. Trends in sub-populations around the island differed. However, island-wide breeding pairs have decreased by − 1.8 ± 0.4% per annum over the past 34 years, particularly driven by breeding colonies in the east-coast section of the island. This overall negative trend differs from the currently stable global trend, but mirrors what is happening in some other parts of the species' sub-Antarctic range. We suggest based on a 50% decrease in breeding pairs over the species' last three generations, and a lack of recent data from Heard Island, Australia's other gentoo penguin breeding site, the species be considered for listing under the Australian Environment Protection and Biodiversity Conservation Act 1999. [ABSTRACT FROM AUTHOR]

Invasive species present a major conservation threat globally and nowhere are their affects more pronounced than in island ecosystems. Determining how native island populations respond demographically to invasive species can provide information to mitigate the negative effects of invasive species. Using 20 years of mark-recapture data from three sympatric species of albatrosses (black-browed Thalassarche melanophris, grey-headed T. chrysostoma, and light-mantled albatrosses Phoebetria palpebrata), we quantified the influence of invasive European rabbits Oryctolagus cuniculus and extreme weather patterns on breeding probability and success. Temporal variability in rabbit density explained 33–76% of the variability in breeding probability for all three species, with severe decreases in breeding probability observed after a lag period following highest rabbit numbers. For black-browed albatrosses, the combination of extreme rainfall and high rabbit density explained 33% of total trait variability and dramatically reduced breeding success. We showed that invasive rabbits and extreme weather events reduce reproductive output in albatrosses and that eliminating rabbits had a positive effect on albatross reproduction. This illustrates how active animal management at a local breeding site can result in positive population outcomes even for wide ranging animals like albatrosses where influencing vital rates during their at-sea migrations is more challenging. [ABSTRACT FROM AUTHOR]

Penguins globally are of conservation concern due to rapid decreases in many populations. Royal penguins (Eudyptes schlegeli) are endemic to Macquarie Island and its offshore islands and the current population status of this species is unknown. Here, we present a contemporary population estimate, undertaken in 2016 using precise global position system technology. Between August and December 2016, all royal penguin colonies were visited and the number of breeding pairs estimated by mapping the perimeters of colonies and applying a nest density estimate. The royal penguin population was estimated at 750,037 breeding pairs (range 669,538-830,154 pairs). The estimate is slightly lower than a previous estimate in 1984, but given the refined methods it was not possible to establish a significant difference or that a decrease in the population has not occurred. Future censuses utilising a consistent methodology are required to more accurately determine the current population trend. Establishing the current status of the royal penguin population will help assess the species vulnerability to several threats that are impacting similar species in the sub-Antarctic region, and inform conservation planning and management. [ABSTRACT FROM AUTHOR]

Understanding divergent biological responses to climate change is important for predicting ecosystem level consequences. We use species habitat models to predict the winter foraging habitats of female southern elephant seals and investigate how changes in environmental variables within these habitats may be related to observed decreases in the Macquarie Island population. There were three main groups of seals that specialized in different ocean realms (the sub-Antarctic, the Ross Sea and the Victoria Land Coast). The physical and climate attributes (e.g. wind strength, sea surface height, ocean current strength) varied amongst the realms and also displayed different temporal trends over the last two to four decades. Most notably, sea ice extent increased on average in the Victoria Land realm while it decreased overall in the Ross Sea realm. Using a species distribution model relating mean residence times (time spent in each 50 × 50 km grid cell) to 9 climate and physical co-variates, we developed spatial predictions of residence time to identify the core regions used by the seals across the Southern Ocean from 120°E to 120°W. Population size at Macquarie Island was negatively correlated with ice concentration within the core habitat of seals using the Victoria Land Coast and the Ross Sea. Sea ice extent and concentration is predicted to continue to change in the Southern Ocean, having unknown consequences for the biota of the region. The proportion of Macquarie Island females (40%) utilizing the relatively stable sub-Antarctic region, may buffer this population against longer-term regional changes in habitat quality, but the Macquarie Island population has persistently decreased (−1.45% per annum) over seven decades indicating that environmental changes in the Antarctic are acting on the remaining 60% of the population to impose a long-term population decline in a top Southern Ocean predator. [ABSTRACT FROM AUTHOR]

Many seabird populations are threatened by interactions with commercial fisheries, and climate change. Understanding their prey requirements and dietary flexibility in this context is important for effective conservation and management. However, changes in the methods used to assess diet, as well as the spatial and temporal coverage of monitoring schemes, may reduce our ability to detect and monitor these marine threats. To help assess conservation priorities linked to diet, we performed a systematic review of 109 albatross diet papers published between 1950 and 2016, which corresponded to 296 studies when stratified by sampling year, breeding site, and breeding species. We assessed the methods used, changes over time, and spatial and temporal sampling coverage by species and island group. Most albatross studies have focused on chick-rearing, and diet during other breeding phases is comparatively poorly known. Furthermore, chicks are more commonly sampled than adults and very rarely immature birds, all of which may differ in diet composition. There was a pronounced shift over time in the preferred method of characterising diet, from the morphological examination of prey remains to stable isotope analysis of tissue. This shift has reduced the volume of detailed taxonomic information available from morphological studies. This difference in resolution hinders the ability to detect changes in prey species, with implications for management of threatened albatrosses and for monitoring broader changes in marine ecosystems. In a knowledge gap analysis for important breeding colonies (with>5% of global population), we identified key sites where existing monitoring has provided a foundation for robust longitudinal diet studies. Maintaining and augmenting these long-term research programmes will enable analyses of the impacts of changing climate and fishing practices on seabird populations and facilitate the timely identification and implementation of management options. [ABSTRACT FROM AUTHOR]

Microsatellite loci are ideal for testing hypotheses relating to genetic segregation at fine spatio-temporal scales. They are also conserved among closely related species, making them potentially useful for clarifying interspecific relationships between recently diverged taxa. However, mutations at primer binding sites may lead to increased nonamplification, or disruptions that may result in decreased polymorphism in nontarget species. Furthermore, high mutation rates and constraints on allele size may also with evolutionary time, promote an increase in convergently evolved allele size classes, biasing measures of interspecific genetic differentiation. Here, we used next-generation sequencing to develop microsatellite markers from a shotgun genome sequence of the sub-Antarctic seabird, the thin-billed prion ( Pachyptila belcheri), that we tested for cross-species amplification in other Pachyptila and related sub-Antarctic species. We found that heterozygosity decreased and the proportion of nonamplifying loci increased with phylogenetic distance from the target species. Surprisingly, we found that species trees estimated from interspecific FST provided better approximations of mt DNA relationships among the studied species than those estimated using DC, even though FST was more affected by null alleles. We observed a significantly nonlinear second order polynomial relationship between microsatellite and mt DNA distances. We propose that the loss of linearity with increasing mt DNA distance stems from an increasing proportion of homoplastic allele size classes that are identical in state, but not identical by descent. Therefore, despite high cross-species amplification success and high polymorphism among the closely related Pachyptila species, we caution against the use of microsatellites in phylogenetic inference among distantly related taxa. [ABSTRACT FROM AUTHOR]

Identifying the impact of introduced predators on endangered prey populations is critical for conservation management. Population viability analysis (PVA) becomes a valuable tool for quantifying such impacts when high quality life history data are available but, surprisingly, predictions from PVA of future population decline have seldom been used directly to assess conservation status. Here we synthesise new research on the unusual life history of the endangered swift parrot Lathamus discolor , an austral migrant that breeds in Tasmania, Australia. Swift parrots are challenging to monitor because (1) spatio-temporal fluctuation in food availability causes them to select entirely different breeding sites each year over a 10,000 km 2 range, and (2) they suffer high but variable rates of predation from introduced sugar gliders Petaurus breviceps depending on where they breed. 50.9% of nesting females on the main island of Tasmania were killed by sugar gliders while incubating eggs, but there was no predation from this source on offshore islands. Over four years 16.5% (0–29%) of the population bred on offshore islands. We use PVAs to examine the likely extent of future population decrease due to sugar glider predation, and demonstrate that the remaining swift parrot population is likely to decrease by 78.8–94.7% (mean over four models = 86.9%) over only three generations (12–18 years). Our models offer a rare example of the use of PVAs for assessing impending population decline and conservation status in species that are challenging to monitor. In this case they support a change of status for swift parrots from “Endangered” to ‘Critically Endangered’ under IUCN criteria. [ABSTRACT FROM AUTHOR]

Regular censuses are fundamental for the management of animal populations but, are logistically challenging for species living in remote regions. The advent of readily accessible, high resolution satellite images of earth mean that it is possible to resolve relatively small (0.6 m) objects, sufficient to discern large animals. To illustrate how these advances can be used to count animals in remote regions, individual elephant seals (Mirounga leonina) were counted using satellite imagery. We used an image taken on 10/10/2011 to count elephant seals (n = 1790±306 (95%CL)) on the isthmus of Macquarie Island, an estimate which overlapped with concurrent ground counts (n = 1991). The number of individuals per harem estimated using the two approaches were highly correlated, with a slope close to one and the estimated intercept also encompassing zero. This proof of concept opens the way for satellites to be used as a standard censusing technique for inaccessible and cryptically coloured species. Quantifying the population trends of higher order predators provides an especially informative and tractable indicator of ecosystem health. [ABSTRACT FROM AUTHOR]

Abstract: Hundreds of thousands of seabirds are killed each year as a result of interacting with longline and trawl fishing operations, and the severity of the impact varies regionally. Shy and white-capped albatrosses, Thalassarche cauta and Thalassarche steadi respectively, are phenotypically similar species known to be incidentally killed by fishing operations. The magnitude of this mortality has not previously been assessed across their range. Here we examine recent effort and bycatch rates in fisheries known to incidentally kill these species and qualitatively evaluate the level of impact of each fishery. Results indicate that over 8500 of these albatrosses may be killed annually, although the reliability of this estimate is low due to the paucity of comprehensive observer data in most fisheries. Of the estimated deaths of all seabird species in the fisheries assessed, trawl and longline fisheries killed birds in approximately equal proportions, but when the mortality levels of shy-type albatrosses were examined, trawl fisheries were responsible for 75% of all deaths. Data suggest most of these birds were killed in South African, Namibian and New Zealand demersal trawl fisheries and the South Africa pelagic longline fishery. Because most adult shy albatrosses are comparatively sedentary and rarely found outside Australian waters, it is primarily juvenile shy albatrosses that regularly encounter fishing fleets known to kill large numbers of albatrosses. In contrast, throughout most of their range juvenile and adult white-capped albatrosses are exposed to fisheries that collectively kill many thousands of these albatrosses each year. These data emphasise the urgent need for robust assessments of the impact of bycatch at a species and population level, and the urgent implementation of effective mitigation measures. [Copyright &y& Elsevier]

Understanding temperature-dependent sex determination in nature often depends on knowledge of species-specific attributes that are integrated into the relationship between temperature and sex. We determined two such attributes for the pig-nosed turtle, Carettochelys insculpta Ramsay, 1886, in tropical Australia: the pivotal range in temperature that separates the male-producing domain from the female-producing domain, and the thermosensitive period during which the embryonic sex is influenced by temperature. The pivotal range for C. insculpta was very narrow, spanning only about 1 °C, and was centered on 32 °C, which is high but consistent with temperatures reported for other tropical species. The thermosensitive period spanned developmental stages 17–21 for temperature influence in the direction of maleness and 18–21 for temperature influence in the direction of femaleness. This period is slightly narrower than that for other reptile species but broadly consistent with the middle third of incubation. [ABSTRACT FROM AUTHOR]

Two related aspects of hatchling emergence were studied in a population of pig-nosed turtles (Carettochelys insculpta) in northern Australia. Using emergence phenology data, nest temperatures, historical weather data, and a developmental model, we tested the hypothesis that delayed hatching occurs in C. insculpta, and that such a delay would allow hatchlings to time their emergence to match the onset of the wet season. Carettochelys insculpta hatchlings emerged, on average, 17 days after dates predicted from a developmental model. Combined with observations of hatchlings remaining in eggs until emergence, these results confirmed delayed hatching in nature. This delay was synchronized with initial river rises associated with the onset of wet-season rains, and is consistent with published criteria for embryonic aestivation. On a diel scale, we generated predictions of two potentially competing models of nocturnal emergence in hatchling turtles based on the knowledge that air temperatures decrease with season during the emergence period. A test of these predictions for C. insculpta produced ambiguous results. However, further analysis indicated that C. insculpta, and probably other nocturnally emerging turtle species, respond to a decline in diel temperature rather than to an absolute temperature. The former would ensure nocturnal emergence, while the latter is experienced during the day as well as at night. Nocturnal emergence may be associated with nesting in open microhabitats.Nous avons étudié deux aspects interreliés de l'éclosion chez une population de Tortues palustres (Carettochelys insculpta) du nord de l'Australie. Nous avons utilisé des données sur la phénologie de l'émergence, les températures au nid, les conditions climatiques du passé, ainsi qu'un modèle de développement, pour tester l'hypothèse selon laquelle l'éclosion est tardive chez C. insculpta et qu'un tel retard permet aux petites tortues de synchroniser leur émergence avec le début de la saison humide. Les C. insculpta néonates ont émergé, en moyenne, 17 jours plus tard que prévu par un modèle de développement. Cette émergence tardive, combinée à l'observation de petites tortues restant dans les oeufs jusqu'à l'émergence, confirme l'émergence tardive en nature. Ce retard est synchronisé à la première crue des rivières associée au début de la saison humide et s'accorde avec les critères de la littérature sur l'estivation des embryons. Deux modèles potentiellement opposés ont généré, sur une échelle de 24 h, des prédictions d'une émergence nocturne chez les tortues néonates, tenant compte que les températures saisonnières baissent pendant la période d'émergence. Un test sur ces prédictions a produit des résultats ambigus dans le cas de C. insculpta. Cependant, une analyse subséquente indique que C. insculpta, et probablement aussi d'autres espèces à émergence nocturne, réagit à une chute de température journalière plutôt qu'à une température absolue. La chute journalière de température entraîne une émergence nocturne, alors que la température absolue est subie autant de jour que de nuit. L'émergence nocturne est peut être reliée à la nidification dans des microhabitats ouverts.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

As the effects of regional climate change are most pronounced at polar latitudes, we might expect polar-ward migratory populations to respond as habitat suitability changes. The southern elephant seal (Mirounga leonina L.) is a pole-ward migratory species whose populations have mostly stabilized or increased in the past decade, the one exception being the Macquarie Island population which has decreased continuously over the past 50 years. To explore probable causes of this anomalous trend, we counted breeding female seals annually between 1988 and 2011 in order to relate annual rates of population change (r) to foraging habitat changes that have known connections with atmospheric variability. We found r (i) varied annually from −0.016 to 0.021 over the study period, (ii) was most effected by anomalous atmospheric variability after a 3 year time lag was introduced (R = 0.51) and (iii) was associated with sea-ice duration (SID) within the seals' foraging range at the same temporal lag. Negative r years may be extrapolated to explain, at least partially, the overall trend in seal abundance at Macquarie Island; specifically, increasing SID within the seals foraging range has a negative influence on their abundance at the island. Evidence is accruing that suggests southern elephant seal populations may respond positively to a reduced sea-ice field. [ABSTRACT FROM AUTHOR]