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We report the depredation by a single Eastern Barn Owl Tyto javanica delicatula on prospecting White-faced Storm Petrels Pelagodroma marina during the re-establishment phase of a colony on Big Island, off Port Kembla, New South Wales, Australia in 2018. Storm petrels were likely extirpated from this colony 56 years previously when invasive weeds rendered their habitat inaccessible. Restoration of vegetation together with storm petrel call broadcasting, commencing in 2014, resulted in significant increases in prospecting numbers, culminating in breeding (three pairs) in the 2017/18 austral summer season. A significant depredation event (> 59 adults) occurred between August and September 2018, providing a set-back to colony establishment. Previously, barn owl depredation on Big Island had been limited to Silver Gulls Chroicocephalus novaehollandiae as prey. However, in the 2018/19 season, the gulls commenced nesting later than usual. The delay appeared to cause the owl to switch target prey. Despite the intense depredation pressure, at least two pairs of storm petrels attempted to breed in the 2018/19 season and 10 birds were trapped and banded at the commencement of the 2019/20 season. Discovery of the mainland roost of the owl was attempted between the two seasons, and its potential death by car strike was investigated. Our findings show that even a single individual predator can have significant impacts on seabird colonies establishing or re-establishing in island environments, especially those under restoration. [ABSTRACT FROM AUTHOR]

We present the first tracked movements of the medium-sized tropical White Tern Gygis alba, using Global Location Sensors (GLS), from a breeding colony on Lord Howe Island, South Pacific, Australia. The tracking period encompassed pre-breeding in 2018 to potential chick provisioning in the following season. Terns remained near Lord Howe Island during breeding, with some pre-egg-laying and post-nestfailure trips 1 000 km distant. The average departure date from Lord Howe Island was 08 April (range: 21 March–22 April). The tern’s migration route was northwest towards the eastern Australian coast, skirting the Great Barrier Reef. Terns then spent the non-breeding period (50% utilisation distribution) in the northwestern Coral Sea bounded by the New Guinea archipelago to the north and North Queensland, Australia, to the west. The mean transit time to the core non-breeding areas was five days (standard deviation ± 2.5 d). The core nonbreeding area was 2 200 km from Lord Howe Island. The mean time spent in the core non-breeding area was 93 d (± 10 d). The return passage completed a clockwise journey with a mean passage time of 12 d (± 3.8 d) and an average arrival on Lord Howe Island of 18 August (range: 08 August–02 September). Over 51% of their core foraging and non-breeding areas were within dedicated marine park networks. We documented the day visits to the island and approximate incubation shifts and nest attendance from changes in light levels of GLS devices. We determined, using saltwater immersion data, that the species exhibited almost no contact with the sea surface during darkness. Peak activity during daylight hours commenced at 12h00, probably indicating resting after foraging at sea. From the limited samples, instrumenting of the terns did not appear to impede breeding attempts during the 14 months of attachment. [ABSTRACT FROM AUTHOR]

Globally, seabird populations have been in decline due to multiple threats throughout their range. Separating simultaneous pressures is challenging and can require significant amounts of data over long periods of time. We use spatial contrasts to investigate the relative importance of several drivers for the purported decline in a species listed as in decline as an example species, the Flesh-footed shearwater (Ardenna carneipes). On Lord Howe Island in the Tasman Sea, Australia, this seabird suffers from habitat loss due to housing development, intensive mortality in fisheries, plastic ingestion, and roadkill due to vehicular traffic on its breeding island. We repeated a quantitative survey of the population to ascertain whether the decline previously reported had continued and to evaluate the purported mortality sources (Reid et al. in PLoS ONE 8(4):e58230, 2013, Lavers et al. in Global Ecol Conserv 17:e00579, 2019). We measured burrow density, area of occurrence, occupancy and breeding success, integrating them with previous surveys using a Bayesian statistical model to generate longer term estimates of demographic rates. We used spatial patterns to test whether mortality on roads or proximity to human habitation was influencing population demographics. In contrast to predictions, we found the population had stabilised or increased. Characteristics such as burrow occupancy and breeding success showed little pattern, with weak evidence for impacts from road mortality and housing development. Such a data-rich approach is substantially more informative and can better support seabird conservation and management efforts does require more field-time and additional equipment than most contemporary surveys, the data is substantially more informative and can better clarify the results of efforts in seabird conservation and management. [ABSTRACT FROM AUTHOR]

Aim Anthropogenic activities alter and constrain the structure of marine ecosystems with implications for wide-ranging marine vertebrates. In spite of the environmental importance of vast oceanic ecosystems, most conservation efforts mainly focus on neritic areas. To identify relevant oceanic areas for conservation, we assessed the year-round spatial distribution and spatio-temporal overlap of eight truly oceanic seabird species of gadfly petrels ( Pterodroma spp.) inhabiting the Atlantic Ocean. Location Atlantic Ocean. Methods Using tracking data (mostly from geolocators), we examined year-round distributions, the timing of life-cycle events, and marine habitat overlap of eight gadfly petrel species that breed in the Atlantic Ocean. Results We compiled 125 year-round tracks. Movement strategies ranged from non-migratory to long-distance migrant species and from species sharing a common non-breeding area to species dispersing among multiple non-breeding sites. Gadfly petrels occurred throughout the Atlantic Ocean but tended to concentrate in subtropical regions. During the boreal summer, up to three species overlapped spatio-temporally over a large area around the Azores archipelago. During the austral summer, up to four species coincided in a core area in subtropical waters around Cape Verde, and three species shared habitat over two distinct areas off Brazil. The petrels used many national Exclusive Economic Zones, although they also exploited offshore international waters. Main conclusions Tracking movements of highly mobile vertebrates such as gadfly petrels can provide a powerful tool to evaluate and assess the potential need for and location of protected oceanic areas. As more multispecies, year-round data sets are collected from wide-ranging vertebrates, researchers and managers will have greater insight into the location of biodiversity hotspots. These can subsequently inform and guide marine spatial planning efforts that account for both conservation and sustainable use of resources such as commercial fisheries. [ABSTRACT FROM AUTHOR]

A translocation of wild-bred and captive-bred Little Penguin Eudyptula minor fledglings was trialled to reinforce (augment) an urban population of this species in Sydney Harbour, Australia. Over three breeding seasons (2004/05 to 2006/07), a total of 44 wild-bred fledglings from nearby Lion Island and 19 captive-bred fledglings from local zoos were translocated to Store Beach, North Harbour, within Sydney Harbour. All translocated birds were implanted with a numbered microchip before release. During the same period, the North Harbour colony produced at least 327 fledglings, of which 113 were implanted with microchips prior to fledging. The North Harbour colony was monitored between 2005 and 2013 to identify any returning translocated or locally wild-bred birds. Three translocated wild-bred birds and 12 locally wild-bred birds are known to have returned to North Harbour, but no translocated captive-bred birds. One translocated wild-bred bird returned to Store Beach while the remaining two returned to adjacent headlands. The number of pairs of Little Penguin breeding on Store Beach, where threats are intensively managed, has increased from one in 2004 to nine in 2013. This study demonstrated that translocation of wild-bred fledglings is feasible. However, because of naturally low return rates, translocations of Little Penguins need to involve a large number of individuals, preferably taken from a sizeable donor colony, to be effective in reinforcing a threatened or declining population. The effectiveness of releasing captive-bred Little Penguins has yet to be demonstrated. [ABSTRACT FROM AUTHOR]

The article discusses a study which examines the introduction, growth, and distribution of White tern on Lord Howe Island, New South Wales. Results show the distribution and abundance of breeding sites, population growth, and success of hatching, breeding, and fledgling. The predators of the species are also mentioned including Lord Howe Pied currawong and Masked owl.

The cover image, by Raül Ramos et al., is based on the Biodiversity Research It is the time for oceanic seabirds: Tracking year‐round distribution of gadfly petrels across the Atlantic Ocean, DOI:10.1111/ddi.12569. Photo Credit: Jacob González‐Solís. [ABSTRACT FROM AUTHOR]

Until its rediscovery on Balls Pyramid in February 2001, the Lord Howe Island Phasmid or Stick Insect ( Dryococelus australis) was thought to be extinct. It disappeared from Lord Howe Island soon after the accidental introduction of the Ship Rat ( Rattus rattus) in 1918. In this paper, we report on the recovery actions undertaken for this critically endangered species since its rediscovery. Monitoring of the small surviving population on Balls Pyramid has shown it to fluctuate between about 9 and 35 adult individuals. As a safeguard against extinction, two adult pairs were removed from Balls Pyramid in February 2003 to establish captive populations in Melbourne and Sydney. Although all four founders bred readily in captivity, one pair died only a month after capture. The second female would have also died soon after capture had it not been for veterinary intervention using novel untested techniques. The single surviving pair bred successfully but the hatch rate of eggs was poor. For the next generation, both fecundity and hatch rates were low. The lack of knowledge regarding the specific husbandry requirements of this particular species undoubtedly contributed to these problems. Careful management, together with a cautious scientific approach, eventually led to all problems being resolved. Presently, there are more than 700 individuals and 14 000 eggs in captivity. Approximately 80% of incubated eggs are expected to hatch. To establish additional captive colonies, adults and eggs have been sent to other institutions, both within Australia and overseas. Now that the species is reasonably secure in captivity, the opportunity exists to reintroduce this iconic insect back onto Lord Howe Island, but this can occur only after the introduced rodents have been removed. A programme to eradicate both the Ship Rat and the House Mouse ( Mus musculus) from Lord Howe Island is currently being developed. [ABSTRACT FROM AUTHOR]

Surprisingly few faunal taxa worldwide have experienced an improvement in conservation status through direct conservation action. One of the few is Gould's Petrel ( Pterodroma leucoptera leucoptera) – a threatened species that breeds only in New South Wales. In the early 1990s, the breeding population of this subspecies was small (<250 pairs) and declining. Each year, adult mortality at the breeding grounds exceeded the number of young produced. A recovery programme, focused on reducing adult mortality, commenced in 1993. As a result of the recovery actions undertaken, the Gould's Petrel is now increasing in numbers. Also, the rainforest where this seabird breeds is now regenerating after being degraded for almost a century by the introduced European Rabbit ( Oryctolagus cuniculus). The creation of artificial nesting habitat and the development of effective translocation procedures have led to the establishment of a second breeding colony of Gould's Petrel, further reducing the risk of extinction. In this paper, we explore the key elements we believe to be responsible for the success of this particular recovery programme: (i) a strong underpinning of robust ecological research; (ii) adaptive management; (iii) monitoring and reporting; (iv) a multidisciplinary approach; and (v) a willingness to accept risk. We conclude with some suggestions to improve the current recovery planning process. [ABSTRACT FROM AUTHOR]

We report the cross-fostering of a Wedge-tailed Shearwater chick by White-necked Petrels during the 2016/17 breeding season in the Norfolk Islands. Our finding highlights the possibility that cross-fostering of these procellariids can be used in conservation applications. [ABSTRACT FROM AUTHOR]

The article discusses the study that determined the effects of short- and long-term deployment of tracking devices on Gould's Petrel Pterodroma leucoptera at Cabbage Tree Island, New South Wales (NSW), during 2010-2011 breeding season. Findings discussed include hatching success, fledging success or chick fledging mass not significantly affected, decline in body mass of adults with geolocators during breeding, similar to those without, and no detectable negative impact in long-term deployment.

It is widely believed that predators maximise their energy intake while foraging and consume prey that are nutritionally similar. We combined GPS data loggers, miniaturised cameras, dietary sampling and nutritional geometry to examine the nutritional variability in the prey and selected diet, and foraging performance, of the masked booby (Sula dactylatra tasmani), a wild carnivore and marine top predator. Data loggers also revealed no significant differences between sexes in the foraging performance of chick-rearing adults. Females provided more food to their chicks than the males and, regardless of the nutritional variability of prey consumed, both sexes showed similar amounts of protein and lipid in their diets. Miniaturised cameras combined with nutritional analysis of prey provided, for the first time, fine-scale detail of the amounts of macronutrients consumed in each plunge dive and the overall foraging trip. Our methodology could be considered for future studies that aim to contribute to the general understanding of the behavioural and physiological mechanisms and ecological and evolutionary significance of animal foraging (e.g. energy expenditure budgets and prey selection for self- and offspring-feeding that could lead to sex-specific foraging strategies). [ABSTRACT FROM PUBLISHER]

Summary Of all the introduced mammalian pests, rodents are the most common invaders of islands and have triggered numerous extinctions around the globe. They have a short gestation period and large litter size, giving them the ability to colonise new areas rapidly. The same biological traits make them difficult to eradicate. Although the biodiversity benefits of removing exotic rodents from islands are increasingly being recognised, there are few published analyses of eradication attempts that critically evaluate eradication tools. This study examined the response of House Mouse ( Mus musculus) populations to an eradication operation on Montague Island, Australia. While the specific impacts of mice have not been studied on this particular island, elsewhere they have been shown to have negative impacts on a range of species including plants, invertebrates, lizards and seabirds. On Montague Island, mouse abundance across different habitats was examined using mark-recapture data collected before and after the deployment of brodifacoum baits. Data obtained before baiting showed significantly lower numbers of mice in sites dominated by exotic grass compared with those dominated by native vegetation. Mouse numbers overall were declining during winter and the population was not breeding, making this an optimal time to undertake the eradication. Trapping immediately after the initial bait drop failed to capture any survivors, and no individuals have been detected during the 3 years since the deployment of baits. This study demonstrated that both small and large baits (0.6 and 2 g pellets) were effective in eradicating the House Mouse from Montague Island. While present, mice were probably slowing the re-establishment of native vegetation by grazing seedlings and consuming seeds. With this pest now gone, the process of natural regeneration is expected to accelerate. The eradication of the House Mouse from Montague is likely to have other positive effects on the island's biodiversity. The operation itself contributed to enhancing local capacity to eradicate exotic rodents from larger or more complex islands. [ABSTRACT FROM AUTHOR]

The article discusses a study on the plastic foraging behavior of Puffinus carneipes, also known as Flesh-Footed Shearwaters, on Lord Howe Island, Australia and its implications for fishery interactions. The repeated-weighing technique was used in the study. The study procedure included estimating food consumption, determining their attendance behavior, and determining their meal size and feeding frequency.