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The use of anticoagulant rodenticides to eradicate invasive rodents from islands has become a powerful tool to prevent species extinctions and to restore degraded ecosystems. Success is dependent on all targeted individuals consuming rodenticide and dying as a result. Because susceptibility to anticoagulants can vary among rodent populations, it is important when planning an eradication to understand the efficacy of the proposed rodenticide on the target animals, particularly where there has been historic exposure to anticoagulants. The aims of this study were to investigate brodifacoum-susceptibility of black rats Rattus rattus and house mice Mus musculus on Lord Howe Island (LHI), Australia, where an eradication program is being planned. Black rats and house mice were subjected to various dosages of brodifacoum in a series of laboratory feeding trials. The results showed that rats on LHI died after consuming doses of rodenticide within expected ranges (60% died at 0.5 mg kg−1 and 100% died at 0.8 mg kg−1) when exposed to bait for 24 h. Mice, on the other hand, were more tolerant of the rodenticide, with 82% of individuals surviving doses of up to 2.0 mg kg−1 consumed over 24 h and some individuals needing 6.0 mg kg−1 consumed over 4 days to ingest a lethal dose. A laboratory experiment designed to simulate field application showed that all mice tested succumbed to brodifacoum poisoning when given the opportunity to consume sufficient bait (at least 6 days of exposure to toxic bait), although some individuals took 22 days to die. The results of these studies will help inform the Lord Howe Island rodent eradication.

Procellariiformes have prolonged incubation shifts, with breeding birds enduring long periods of fasting and substantial reductions in body mass. These changes can be physically demanding and parents must balance their own energy requirements with the needs of their unhatched young. The incubation routine and associated changes in body mass of breeding Gould’s Petrel (Pterodroma leucoptera) were studied to explore the relationships between body mass, incubation shift duration and nest desertion. The incubation routine of Gould’s Petrel was similar to other Procellariiformes, although shift length was particularly long for a bird of this size. Failure to complete incubation was due to egg damage or nest desertion. Temporary egg abandonment was observed in successful as well as in failed breeders, although eggs abandoned for longer than 1 day all failed. Nest desertions generally occurred before the normal duration of the incubation shift rather than after excessively long shifts caused by the late return of the partner. We conclude that incubation success was limited by both the condition of birds at the start of the shift and their tenacity to remain until relieved by their partner.

Little is known of the Endangered Lord Howe Island Cockroach Panesthia lata Walker, 1868, other than that it disappeared from Lord Howe Island following the introduction of ship rats Rattus rattus (Linnaeus, 1758) in 1918. With a rodent-eradication programme being planned for Lord Howe Island, an opportunity exists to reintroduce P. lata once rodents have been removed. Previous brief surveys of other islands within the Lord Howe Group have found that P. lata still occurs on some of these islands. In this study, further surveys were conducted on two of those islands (Blackburn and Roach) to gain a better understanding of the distribution and abundance of P. lata there and to investigate potential survey techniques. Brief observations were also made of the behaviour and ecology of the species. Extrapolation from survey plots showed that although 60% of the estimated population of 10 000 individuals on Blackburn Island were living beneath the sole Banyan Ficus macrophylla Desf. tree, P. lata was widely distributed across the island, utilising both native and exotic vegetation, including the introduced Rhodes Grass Chloris gayana Kunth. On Roach Island, the bulk of the estimated population of 3500 individuals occurred within Leafy Flat Sedge Cyperus lucidus R. Br. habitat. Panesthia lata seemingly spends considerable time sheltering within refuges rather than foraging on the surface; consequently, population estimates based on surface counts are underestimates. Improving either the accuracy or precision of these counts risks damaging individuals and their habitat. Mark-recapture techniques were not applicable for assessing the abundance of this species, but trials of novel attraction stations indicated that such devices could be useful for monitoring distribution and gross fluctuations in population size. Panesthia lata appears to feed on any dead vegetation, but primarily leaves. Individuals were relatively sedentary overnight, sheltering by day under any object that provided the appropriate microenvironment. Soil characteristics in areas where P. lata sheltered were significantly modified, suggesting that this species may play an important role in soil conditioning and nutrient cycling. Maintaining the rodent-free status of islands on which P. lata occurs is a high priority for this species.

For most passerines, nest predation has a major impact on breeding success; however, information on the identity of nest predators is scant. In 2012, we investigated the identity of nest predators that each year depredate about 50% of the nests of 21 species in a south-east coastal bird community in New South Wales, Australia. The current study is a 2-year extension of this study and shows that at this study site (a) predation accounts for at least 90% of nest failures, (b) identified nest predators comprised two reptiles, nine birds and five mammals, (c) the suite of predators changes each season, (d) the two major predators were the Eastern Whipbird (Psophodes olivaceus) and the Fan-tailed Cuckoo (Cacomantis flabelliformis), (e) the impact of the Red Fox and Feral Cat was minimal, and (f) there was a variable and complex interaction between the parasitic cuckoos and their hosts. The data show definitively the overwhelming importance of nest predation on fledgling production, and bring to light new and important data on several aspects of the suite of nest predators.

Seabird life-history traits such as long generation time, low annual fecundity and delayed sexual maturation make them more prone to population loss and consequently to extinction; petrels are indeed amongst the most threatened birds. Based on coalescence and multiloci inference this study examines the extent of genetic differentiation of a vulnerable New Caledonia (caledonica) and Australia (leucoptera) subspecies of Pterodroma leucoptera (Gould’s Petrel), and whether the genetic relationship between them results from the influence of past events like variation in sea level, or is dominated by contemporary gene flow. Sequences of two mitochondrial genes and five nuclear introns were obtained from 86 individuals from both populations. Haplotype networks were used to infer relationships between the haplotypes of both populations. The demographic history of the P. leucoptera complex was studied using neutrality tests and Extended Bayesian Skyline Plots. A weak population differentiation was revealed. The Extended Bayesian Skyline plot suggested a population expansion approximately 80,000 years before present (bp) for caledonica and 30,000 years bp for leucoptera. The split was dated to 30,000 years bp by means of multilocus inference through *BEAST. Despite genetic similarity of the two taxa, we advocate to consider them as independent units for conservation management, given their strong ecological distinctiveness (foraging distribution, winter distribution, breeding phenology and breeding distribution).

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 th...

Objectives The objective of this study was to investigate the silver gull as an indicator of environmental contamination by salmonellae and carbapenemase-producing Enterobacteriaceae (CPE) in south-east Australia. Methods A total of 504 cloacal samples were collected from gull chicks at three nesting colonies in New South Wales, Australia [White Bay (n = 144), Five Islands (n = 200) and Montague Island (n = 160)] and were examined for salmonellae and CPE. Isolates were tested for carbapenemase genes and susceptibility to 14 antibiotics. Clonality was determined by PFGE and MLST. Genetic context and conjugative transfer of the carbapenemase gene were determined. Results A total of 120 CPE of 10 species, mainly Escherichia coli (n = 85), carrying the gene blaIMP-4, blaIMP-38 or blaIMP-26 were obtained from 80 (40%) gulls from Five Islands. Thirty percent of birds from this colony were colonized by salmonellae. Most isolates contained the gene within a class 1 integron showing a blaIMP-4-qacG-aacA4-catB3 array. The blaIMP gene was carried by conjugative plasmids of variable sizes (80–400 kb) and diverse replicons, including HI2-N (n = 30), HI2 (11), A/C (17), A/C-Y (2), L/M (5), I1 (1) and non-typeable (6). Despite the overall high genetic variability, common clones and plasmid types were shared by different birds and bacterial isolates, respectively. Conclusions Our data demonstrate a large-scale transmission of carbapenemase-producing bacteria into wildlife, likely as a result of the feeding habits of the birds at a local waste depot. The isolates from gulls showed significant similarities with clinical isolates from Australia, suggesting the human origin of the isolates. The sources of CPE for gulls on Five Islands should be explored and proper measures applied to stop the transmission into the environment.

Highlights • We examined blood smears from 263 wild little penguins in southeastern Australia. • Babesia sp. was detected in penguins in New South Wales, Victoria and Tasmania. • True prevalence is estimated between 3.4% and 4.5%. • Babesia sp. from little penguins is closely related to B. poelea and B. uriae. • Babesia infections were assymptomatic., Graphical Abstract, Blood parasites are potential threats to the health of penguins and to their conservation and management. Little penguins Eudyptula minor are native to Australia and New Zealand, and are susceptible to piroplasmids (Babesia), hemosporidians (Haemoproteus, Leucocytozoon, Plasmodium) and kinetoplastids (Trypanosoma). We studied a total of 263 wild little penguins at 20 sites along the Australian southeastern coast, in addition to 16 captive-bred little penguins. Babesia sp. was identified in seven wild little penguins, with positive individuals recorded in New South Wales, Victoria and Tasmania. True prevalence was estimated between 3.4% and 4.5%. Only round forms of the parasite were observed, and gene sequencing confirmed the identity of the parasite and demonstrated it is closely related to Babesia poelea from boobies (Sula spp.) and B. uriae from murres (Uria aalge). None of the Babesia-positive penguins presented signs of disease, confirming earlier suggestions that chronic infections by these parasites are not substantially problematic to otherwise healthy little penguins. We searched also for kinetoplastids, and despite targeted sampling of little penguins near the location where Trypanosoma eudyptulae was originally reported, this parasite was not detected.

The Providence Petrel (Pterodroma solandri) currently breeds only on Lord Howe and Phillip Islands and is globally threatened. It once bred on Norfolk Island in large numbers but was extirpated by the late 18th century, greatly reducingtheinfluxofmarine-derivednutrientsintheformofdroppings,andfailedeggsandchicks.Thislackofnutrientshas impairedthehealthoftheremainingnativeforestsonNorfolkIsland.There-establishmentofacolonyofProvidencePetrels onNorfolkIslandwouldnotonlyprovideanotherviablebreedingcolonyofthisthreatenedspeciesbutisessentialtorestore ecosystemfunctiononNorfolkIsland.ThispaperinvestigatesthebiologyofProvidencePetrelchicksasaprerequisiteforthe translocation of this species to Norfolk Island from Lord Howe. Petrels are highly philopatric, so only chicks not yet imprintedattheirnatalcolonycanbetranslocated.Weinvestigatedthetimingof firstemergencefromtheburrow,growthand provisioning of chicks on Lord Howe Island, and developed selection and ageing criteria for translocation, together with appropriate feeding regimes. Such information is critical for the success of the proposed translocation.

International audience; Niche divergence is expected for species that compete for shared resources, including migrants that occupy similar regions during the non-breeding season. Studies of temperate seabirds indicate that both spatial and behavioural segregation can be important mechanisms for reducing competition, but there have been few investigations of resource partitioning by closely related taxa in low productivity, tropical environments. We investigated niche partitioning in 3 gadfly petrel taxa, Pterodroma leucoptera leucoptera (n = 22), P. leucoptera caledonica (n = 7) and P. pycrofti (n = 12), during their non-breeding season in the eastern tropical Pacific Ocean by combining tracking data from geolocator-immersion loggers with remotely sensed environmental data in species distribution models (SDMs), and by comparing feather stable isotope ratios. The 3 taxa showed spatial partitioning: two foraged in the North Equatorial Counter Current and one in the South Equatorial Current. This reflected differences in their realised habitat niches, with significant taxon-specific responses to thermocline depth, sea surface temperature and bathymetry. There were also differences among taxa in activity patterns, and all birds spent a much larger proportion of time in flight at night than during the day, suggesting predominance of nocturnal foraging behaviour. Comparison of stable isotope ratios in feathers suggests that P. l. leucoptera and P. pycrofti mainly consume vertically migrating mesopelagic fishes, whereas the diet of P. l. caledonica also includes some lower trophic levels including crustaceans and squid. Unique insights can be gained from studies of the foraging ecology of tropical pelagic seabirds, in comparison with temperate and polar waters, and are urgently required for understanding and protecting tropical avifauna in key marine habitats.

SummaryThe Bermuda Petrel Pterodroma cahow was thought to have become extinct early in the 17th century due to a combination of hunting by human colonists and predation by introduced rats, cats, dogs and pigs. However, single individuals were found on four occasions during the first half of the 20th century, and in 1951 a small population was discovered breeding on several rocky islets in north-east Bermuda. Recovery actions began in 1962 when the population numbered just 18 pairs, dispersed among five small islets. Although rats extirpated one of these five colonies in 1967, the population has grown steadily to 56 breeding pairs in 2000. We investigated the breeding phenology, productivity and population size of the Bermuda Petrel between 2000/2001 and 2007/2008. Each year, the birds began arriving in Bermuda around mid-October. They departed on a pre-breeding exodus between 19 November and 14 December, returning after 32–56 days to lay a single egg between 31 December and 31 January. Eggs hatched from 16 February to 26 March after a mean (± SD) incubation period of 53 ± 2 days, and young fledged from 15 May to 25 June after a mean fledging period of 91 ± 5 days. Between 2000/2001 and 2007/2008, reproductive output ranged from 29 to 40 fledglings per annum. Mean annual breeding success (62%) was reasonably high relative to other Procellariiformes, largely due to the provision of artificial (concrete) nesting burrows. In 2008, the population numbered 85 breeding pairs. Monitoring since 1961 indicates the population has been increasing exponentially, doubling approximately every 22 years. This rate of increase, together with the increased incidence of storm damage, is making it progressively more impracticable to construct sufficient concrete burrows on the current nesting islets to accommodate all breeding pairs. The vulnerability of these sites to accelerating storm damage and erosion as a result of anthropomorphic climate change is now the greatest threat to the Bermuda Petrel.

SummaryUntil recently, Bermuda Petrel Pterodroma cahow (IUCN Category: ‘Endangered’) bred only in sub-optimal habitat on four small islets in north-east Bermuda. Although intensive management of the population since 1962 has led to a substantial increase in population size (now approaching 100 pairs), the nesting habitat on these four islets is being increasingly inundated, eroded and destroyed by high seas associated with hurricanes and storms. To ensure the long-term conservation of the species a decision was made to establish a new colony at a more secure site on nearby Nonsuch Island, where they once bred in large numbers. Between 2004 and 2008, 104 near-fledged nestlings were translocated to artificial burrows on Nonsuch Island, where they were hand-fed meals of fish and squid. All but three translocated birds fledged successfully, with the first returning to Nonsuch Island in February 2008. The first Bermuda Petrel egg on Nonsuch Island in more than 300 years was laid in January 2009, and the resultant fledgling departed in June of the same year. By the end of the 2009/10 breeding season, a total of 18 Bermuda Petrels have been recorded on Nonsuch Island, 17 were translocated as near-fledged nestlings, and one bird came from the existing colonies. A total of five eggs have been produced, resulting in two fledglings. The establishment of this new colony, at a site that is much more secure than the existing nesting sites, greatly enhances the conservation prospects of the species and demonstrates the importance of translocation as a tool for the conservation of threatened seabirds.

Australia's most widespread palm, the Cabbage Tree Palm Livistona australis (R. Br.) Mart. has only a few offshore populations, but one of considerable significance is on Cabbage Tree Island on the mid-north coast of New South Wales. This island is also the principal breeding site of a threatened endemic seabird, the Gould's Petrel Pterodroma leucoptera leucoptera. This paper outlines some of the ecological interactions between this iconic palm and this enigmatic seabird. P. leucoptera nests in rock cavities, under fallen palm leaves, or in hollow fallen palm trunks. It takes to the air by climbing to the top of palms and is sometimes killed by colliding with them. The eradication of the European Rabbit Oryctolagus cuniculus from Cabbage Tree Island in 1997 was undertaken to remove one of the threatening processes endangering P. leucoptera. This action has in turn released the population of L. australis from 91 years of unsustainable grazing pressure, helping to restore the long-term integrity of this, an...

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.

Summary 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.

Summary 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 (

Although most Little Penguins (Eudyptula minor) breed on offshore islands, several small colonies occur on the mainlands of New Zealand and Australia, including mainland Tasmania. Unlike island colonies, most mainland colonies have declined over recent decades, several having gone extinct. A mainland colony of Little Penguins in North Harbour, Sydney, Australia, was monitored over three consecutive breeding seasons (2002–03 to 2004–05). The number of known nesting pairs was 49–56 per annum. The mean number of eggs laid per pair (2.45), eggs hatched per pair (1.84), fledglings produced per pair (1.71), hatching success (0.72) and breeding success (0.70) were among the highest reported from Australian colonies. Underlying these figures was a particularly high proportion of pairs that double-brooded (14–31% per annum, mean 24%). Fledging mass as a percentage of mean adult mass (103%) was also high. Together, these results suggest that food at the North Harbour colony was abundant during the period of study. Fledglings first returned to the colony at 1–4 years of age and first bred at 2–4 years of age. The recruitment rate of fledglings produced at the North Harbour colony was up to 15%, much higher than that recorded elsewhere. Banding recoveries (1997–2005) show that the North Harbour colony contains a substantial number of immigrants that have come from as far afield as Phillip Island, 761 km south of Sydney. Individuals banded at North Harbour have been recovered as far away as Sydenham Inlet, Victoria, 485 km to the south. The mixed provenance of the North Harbour population demonstrates that it is not isolated, either demographically or genetically, from other colonies in south-eastern Australia.

Knowledge of the habitat requirements of threatened species at both local and landscape scales is crucial for maintaining viable populations and for making conservation and management decisions. Here, we use live trapping and radio-tracking to investigate habitat use by four species of threatened marsupials – burrowing bettongs ( Bettongia lesueur ), brush-tailed bettongs ( B. penicillata ), greater bilbies ( Macrotis lagotis ), and bridled nailtail wallabies ( Onychogalea fraenata ). The study populations had been re-introduced to Scotia Sanctuary in western New South Wales, Australia, within a predator-proof area. All showed preferences for particular macrohabitats while resting by day, with M . lagotis and B . penicillata selecting Eucalyptus woodland with Triodia understorey and B . lesueur and O . fraenata selecting Eucalyptus woodland with shrubs. However, they showed no such partiality at night. Bettongia penicillata used areas with Triodia and litter but few herbs for shelter, while burrows of M. lagotis avoided shrubs. Habitat components that influenced trap captures were: crust cover and herb layer cover (negative) for B . penicillata , trees B . lesueur, crust cover for M . lagotis , and crust cover and trees O. fraenata (both negative). There was also a negative association at this scale between B. penicillata and both B. lesueur and M. lagotis , suggesting the possibility of competition. Our results support the idea that studies at multiple spatial scales are crucial to understand the habitat use and requirements of threatened fauna, and should therefore be incorporated into future re-introduction programs.

Malleefowl (Leipoa ocellata) are in decline across their range. Previous studies have found that the survival rate of young Malleefowl is low, the single greatest cause of mortality being predation by the introduced Red Fox (Vulpes vulpes). Many of these studies, particularly those in New South Wales (NSW), were conducted in habitats that were heavily modified by fire, exotic herbivores or plant harvesting. In this paper, we examine the survival of Malleefowl in relatively undisturbed mallee habitats within two conservation reserves in South Australia (SA). Both reserves were long unburnt and free of large exotic herbivores, but differed greatly in understorey structure. Fifteen young captive-reared Malleefowl were released into each reserve. In all, 70% of these individuals were dead within 40 days. Fox predation was the prime cause of mortality, accounting for at least 30%, and perhaps as much as 96%, of all deaths. The extent and causes of mor- tality were similar in the two reserves. The overall level of Malleefowl survival was (1) better than that recorded in more disturbed habitat in NSW in the absence of any Fox control, but (2) substantially less than that in NSW after widespread Fox control was implemented. This study indicates that Malleefowl in SA are subject to significant levels of Fox predation, even in relatively undisturbed habitats. Also, for the two mallee habitats examined, evidence suggests that understorey structure had no influence on the degree of predation. Available data indicate that during the past two decades Malleefowl populations in SA have declined at about the same rate as those in NSW. Current densities in SA are typically about one- quarter of what they were 15 years ago. We conclude that habitat integrity and structure have little effect on the interaction between Foxes and Malleefowl, and suggest that Malleefowl populations across Australia are threatened by Foxes, placing the species at substantial risk of extinction.

Summary 1The pituitary hormone prolactin is thought to play an important role in the promotion of parental care in birds and mammals. The level of care parents provide is, however, likely to be influenced by additional factors, such as their physiological condition at the time of breeding. 2We examined relationships between parental body condition, plasma prolactin levels and reproductive performance in Gould's Petrels (Pterodroma leucoptera), a long-lived seabird. We predicted that parental body condition would correlate positively with both prolactin level and parenting intensity, as measured by the quality of the chick they produced. We also examined the effects of parenting intensity on parental body condition and reproductive success in the subsequent breeding season. 3Body condition of male parents positively correlated with prolactin levels at the start of their second protracted incubation bout. The body condition of both parents correlated positively with the body condition of their chick at its peak mass. However, producing a good-quality chick did not negatively affect parental body condition or reproductive success the following year. 4These results suggest that prolactin reinforces parental behaviour in parents in good body condition, which facilitates production of good-quality chicks. Moreover, good-quality parents consistently produce good-quality chicks with no apparent trade-off to their physical condition.

Many petrels show no obvious sex-linked dimorphism in plumage or size and consequently many researchers fail to sex the living individuals they study. Several methods of sex discrimination that do not rely on plumage- or obvious size-dimorphism can be used to sex live petrels. The effectiveness of three such techniques was evaluated: body condition at the time of laying, cloacal inspection, and discriminant function analysis (DFA) of external morphometrics. Gould’s Petrel (Pterodroma leucoptera leucoptera) was used as the subject species. Sexing of breeding adults on the basis of body condition at laying proved to be highly accurate (100% of birds sexed correctly) but required detailed knowledge of the breeding biology. Following training, cloacal inspection proved to be an accurate (96%) method of determining the sex of breeding adults, but not of chicks. Unlike molecular sexing, the latter two methods of sex discrimination provide immediate knowledge of the sex of individuals in the field. DFA of external morphometrics predicted the sex of adults with an accuracy of 73% and the sex of near-fledged chicks with an accuracy of 66%. However, the probability of correct assignment of sex was low in most cases and, therefore, this is the least useful of the three techniques assessed here.

Gould’s petrel (Pterodroma leucoptera leucoptera) was restricted, essentially, to a single breeding locality – Cabbage Tree Island, Australia. As a safeguard against extinction, an additional breeding colony was established on nearby Boondelbah Island, where artificial nesting habitat was created by installing 100 plastic nest boxes. Over two years, a total of 200 nestling Gould’s petrels were translocated from Cabbage Tree Island to these boxes. Colonies on both islands were then monitored for a further four years. Selection of nestlings for transfer was based on prior knowledge of growth, plumage development and emergence from the burrow, and aimed to select only birds that were 11–28 days from fledging (DBF) in 1999 and 11–22 DBF in 2000. Of the first 100 nestlings translocated to Boondelbah Island (in March 1999), 95 fledged successfully 8–27 days after transfer (mean = 17.3 days). Of the second 100 nestlings translocated (in March 2000) all successfully fledged 9–22 days after transfer (mean = 15.1 days). The removal of young had no discernible effect on the subsequent breeding productivity of the donor pairs. In all, 41 Gould’s petrels have been recorded at the new colony on Boondelbah Island, where at least 27 nest boxes have been visited. Ten translocated fledglings (nine male, one female) have returned to the translocation site, taking up nest boxes that were, on average, 5.5 m from the box from which they fledged. An additional 27 non-translocated birds, of unknown origin, have also nested in nest boxes on Boondelbah, along with four birds previously known from Cabbage Tree Island. Two nestlings transferred to Boondelbah Island have returned to Cabbage Tree Island. Within five years of the first translocation, the newly established colony on Boondelbah Island has produced a total of 24 eggs and 14 fledglings. The translocation technique developed for Gould’s petrel has broad applicability, being readily adaptable for other burrow-nesting seabirds.

The flesh-footed shearwater (Puffinus carneipes) is a migratory seabird that ranges widely across the Pacific and Indian Oceans. The principal breeding populations are in Australia and New Zealand. The only breeding site in eastern Australia is on Lord Howe Island. Despite it being afforded a high level of legislative protection, the population on Lord Howe Island has declined substantially during the last few decades. The total extent of nesting habitat in 2002 was 24.3 ha, a reduction of 13.4 ha (35.6%) since 1978. Loss of nesting habitat was associated with increased urbanisation, the adverse impact of which extended beyond the footprint of buildings and gardens. In 2002, overall burrow density was 0.123 per m2 and the total number of burrows was estimated to be 29,853 ± 5867, a decline of about 19.0% since 1978. A substantial decline in burrow density was evident in the colony where loss of habitat to urbanisation had been greatest. In 2002, 58% of burrows were occupied by breeding birds, and the total population size was estimated to be 17,462 breeding pairs. Breeding success (the proportion of eggs that produced fledglings) was 50%, but was lowest in the most urbanised colony. To avert further declines in the population of flesh-footed shearwaters on Lord Howe Island major changes in land use practices, enforced through appropriate legislation, are needed, together with reductions in the level of seabird bycatch in fisheries operations and in the amount of plastics that litter the world’s oceans.

The breeding biology and reproductive output of a colony of Masked Boobies on Mutton Bird Point, Lord Howe Island, Australia, were studied during the 2001–02 breeding season. The colony produced a total of 200 clutches. Eggs were laid between 31 May and 15 September 2001, with 80% of clutches begun before 21 July. More than 90% of clutches consisted of two eggs, laid, on average, 5.3 days apart. Mean incubation period was 45 days. Where both eggs hatched, the later-hatched chick had to compete with an aggressive elder sibling of greater mass; consequently, it seldom survived longer than 1 week. Hatching success was 38% for single-egg clutches, 81% for two-egg clutches and 78% overall. For two-egg clutches, 13% of successful chicks hatched from the second egg. In keeping with the comparative mass of adults, eggs and chicks from Lord Howe Island were larger than those from any other Masked Booby population where measurements have been made. Chick mass increased steadily to reach a maximum of 2235 ± 292 g (equivalent to mean adult mass) at 11 weeks of age. Overall, fledging success was 65%, but was greatest for eggs laid early in the breeding season. There was no difference in fledging success between chicks that were handled weekly and those that were handled only once. Overall breeding success was 51%. Rats were not a significant predator of eggs or chicks, and no other predators or land-based threats were identified. Clutch-size indicated that, at the time of laying, the Masked Booby population on Lord Howe Island was well nourished, but decreasing rates of hatching and fledging success, and less than optimal growth rates of chicks, suggested food availability declined during the nesting period. Regurgitations indicated that flying fish were the main prey.

Little Shearwaters, Puffinus assimilis assimilis, were thought to have disappeared from Lord Howe Island during the early 1900s. This study reports Little Shearwaters breeding on Lord Howe Island between 1990 and 2001. A survey in 2000 recorded 85 nestlings. It is unclear whether this species has persisted on Lord Howe Island in low numbers throughout last century or whether it is recolonising. Adults, ashore between April and October, often occupied burrows previously used by Black-winged Petrels, Pterodroma nigripennis. Observations at a single nest showed the incubation period to be 55 days and the nestling period to be 72 days. Chick mass increased at a mean rate of 5.2 g day–1 to a maximum of 272 g at 48 days old. The chick fledged on 5 November at 158 g after fasting for six days. During chick rearing, parents came ashore almost nightly, arriving just after sunset and remaining with the chick until shortly before dawn; occasionally they were ashore during the day.

The Black-winged Petrel, Pterodroma nigripennis, is a recent coloniser of Lord Howe Island, with adults present between late October and early May. Four nests were monitored during both the 1989-90 and 1990-91 breeding seasons. Eggs were laid at the end of December and hatching occurred in mid February after 45.3 ± 0.5 days' incubation (mean ± s.d.). Young (weighing 175.5 ± 8.7 g) fledged in early May, 84.8 ± 0.5 days after hatching and 10.3 ± 1.6 days after feeding stopped. On average, chicks were fed every 2.5 days, with each parent returning every 4.4 days. Provisioning rates remained constant throughout the period of chick rearing. Average meal size was estimated at 32.6 g. Inter-specifi c competition for nesting burrows with Little Shearwaters, Puffinus assimilis, was observed.

International audience; This study describes and compares the pelagic distribution and migratory patterns of the two subspecies ofGould’s Petrel (Pterodroma leucoptera), and contrasts data obtained from tracking birds at sea using geolocators withobservational data (shipboard sightings, by-catch records and beachcast specimens). While breeding, tracked individuals ofboth subspecies (P. l. leucoptera and P. l. caledonica) foraged within the Tasman Sea and south of the Australian continent,with forays west into the Indian Ocean before laying. After breeding, both subspecies migrated to distinct non-breedingranges within the eastern tropical Pacific Ocean. Observational data identified the general pattern of migration and foragingareas of the species, whereas data from geolocators provided details of routes and timing of migration, core foraging ranges,and marked spatial and temporal segregation between the two subspecies. However, by attaching geolocators only toestablished breeders, as is typical of studies of small and medium-sized seabirds, these devices failed to identify that nonbreedingbirds (pre-breeders and adults that are deferring breeding) may not follow the same migratory schedules or have thesame at-sea distribution. We conclude that integrating data from electronic tracking with observational data substantiallyimproves our understanding of the pelagic distribution of seabird populations.

Aside from a few pairs recently discovered breeding on nearby Boondelbah Island, the Gould’s Petrel (Pterodroma leucoptera leucoptera) is limited to a single breeding colony located on Cabbage Tree Island, New South Wales. The translocation of birds from Cabbage Tree Island to establish a new colony elsewhere, or to augment the small colony on Boondelbah Island, is an option currently being considered to aid the long-term conservation of this endangered species. We undertook a trial translocation of nestlings within their current breeding grounds on Cabbage Tree Island. This involved removal of the nestlings from the natal nest, denying them further parental care, relocating them to an artificial nest box and feeding them artificially. Thirty nestlings were translocated between gullies on Cabbage Tree Island after they had attained specific plumage characteristics thought to occur just prior to their first emergence from their nests. The translocated nestlings were confined to their adopted nest boxes for the first 3 days and artificially fed every third day until they fledged. The experimental translocation and the associated use of artificial feeding resulted in a small increase in fledging weight, but caused no reduction in fledging success, and had no effect on the timing of departure of the fledglings. Three translocated fledglings have returned to Cabbage Tree Island since their departure in April 1995; all returned to their adopted nest site, one being recovered only a few metres from the nest from where it fledged. This study demonstrated that translocations of Gould’s Petrel nestlings can be achieved without any discernible detriment to the individual birds involved.

The endangered Gould's petrel ( Pterodroma leucoptera leucoptera ) nests, almost exclusively, in rainforest on Cabbage Tree Island, New South Wales, Australia. Since their introduction in 1906, European rabbits ( Oryctolagus cuniculus ) have greatly changed the structure of the rainforest, threatening its existence and that of the petrel. Rabbits were eradicated by sequential epizootics of myxomatosis and rabbit haemorrhagic disease (RHD), and a single application of cereal-based bait (Talon® 20P) containing the anticoagulant brodifacoum. The effectiveness of these mortality agents was evaluated by monitoring 70 telemetered rabbits, half of which were vaccinated against RHD. A natural epizootic of myxomatosis from May to July 1997 reduced the rabbit population from about 250 to 100. RHD, released in August 1997, reduced the population by a further 55%, the rabbits dying within 4–23 days. No survivors tested positive to RHD antibodies. Aerial baiting in September 1997 eradicated all remaining rabbits within 13 days. Intensive monitoring over the next 6 months detected no survivors. Non-target deaths included two buff-banded rails ( Gallirallus philippensis ) and one pied currawong ( Strepera graculina ).

A Bryde's whale, Balaenoptera edeni, was rescued after having been entrapped in the Manning River, Australia, for 100 d. Blood, skin, and epidermal tissue were analyzed to determine the whale's taxonomic status, gender, and health. This paper reports the results of these analyses and discusses the findings in relation to the potential physiological damage to the whale from its protracted stay in the river. Molecular genetic analysis of epidermal tissue identified the whale as a male of the rare pygmy form of Bryde's whale. The 10.3-m whale was diagnosed as emaciated, parasitized, under stress, and in a state of profound catabolism at the time of its rescue. Although it had greatly depleted its energy reserves, the whale was rescued from the river before the onset of ill health or irreparable physiological damage. No organ dysfunction was evident with the possible exception of some deterioration in kidney function most likely caused by parasitism. The whale swam away srongly on release, and its chances of survival appeared to be good.

In August 1994 a Bryde's Whale Balaenoptera edeni entered and became entrapped in the Manning River, New South Wales. The individual was an immature male of the rare pygmy form of Bryde's Whale: it was 10.3 m long and weighed approximately 7.7 tonnes. The whale remained in the river for 100 days, during which time observations were made of its movements, diving habits, feeding behaviour and body condition. Apart from the risk of stranding, the entrapped whale also faced the potential threats of starvation, entanglement in fishing nets, collision with boat traffic, and exposure to low salinity and high acidity. In view of these threats, a rescue bid was launched to return the whale to the ocean. Five rescue attempts were made the last culminated in the whale being successfully towed to sea and released several kilometers offshore. Despite its emaciated condition the whale was rescued from the river before the onset of ill health or irreparable physiological damage. The whale swam away strongly on release, ...

Prime mallee lands that once supported high densities of malleefowl, Leipoa ocellata in New South Wales have been extensively cleared for agriculture. Malleefowl are now restricted largely to more arid habitat. Given the added competition from introduced herbivores, there is concern that these marginal habitats may not contain sufficient food resources to support viable populations of malleefowl, particularly in times of drought. An opportunistic feeding strategy and omnivorous diet enable malleefowl to exploit a diverse array of food items. Vegetative and invertebrate food resources available to malleefowl in marginal mallee lands were monitored over a period of 1 year during drought. Food resources were varied, transient and patchily distributed. Composition and abundance fluctuated considerably, but potential food was never entirely absent. Despite the prevailing drought, food was obtainable throughout the year provided malleefowl adapted to the fluctuating availability of each of the various potential food resources. Reduced food resources in marginal habitat is not implicated as a major factor in the demise of the malleefowl. Food was most abundant between August and November, inclusive, due largely to the abundance of herbs, the diverse supply of buds, flowers and fruit on perennial shrubs, and the sporadic proliferation of cockroaches. Food availability was least, and therefore most critical, during February, March and June. The most favourable time of the year, in terms of available food resources, for the release of captive-bred individuals was during spring, around September.

Captive-reared juvenile Malleefowl Leipoa ocellata (3-5 months old) experimentally released into Yathong Nature Reserve did not survive. From the first day after release Malleefowl were found dead, and mortality continued at a rapid rate until none remained alive: 50-58% were dead within 7 days; 83-96% were dead within 36 days; and none survived longer than 104 days. Predation by the introduced Red Fox Vulpes vulpes was the principal cause of mortality, accounting for at least 50% and perhaps as many as 92% of young Malleefowl. Twelve older captive-reared sub-adults (14-28 months of age) experimentally released into Yathong Nature Reserve fared somewhat better; three survived longer than 428 days. Again, predation by foxes was the chief cause of mortality. Mortality was particularly high during the first week following liberation, but the two age classes differed in their long-term survival. One third of sub-adults survived to breeding age (2.5 years), while no juvenile survived its first year. This implies a decrease in the vulnerability of Malleefowl to foxes between the first and subsequent years of life. Predation by foxes remained the major cause of mortality among sub-adults. Fox predation may well threaten the continued survival of Malleefowl in New South Wales because they killed sub-adult Malleefowl of a weight comparable to that of many adults, which suggests that the duration of vulnerability to foxes is protracted. Furthermore, this threat is not confined to the fragmented remnants of mallee vegetation within the wheat-belt but extends to Malleefowl populations in the remaining large expanses of mallee, remote from agriculture.

(1995). An Artificial Nest Box For Burrow-Nesting Seabirds. Emu - Austral Ornithology: Vol. 95, No. 4, pp. 290-294.

The remains of adult Gould's Petrels Pterodroma leucoptera leucoptera were recovered from the nesting site on Cabbage Tree Island, New South Wales. Entanglement in the sticky fruits of the Bird-lime Tree Pisonia urnbellifera was identified as a major cause of mortality. Removal of P. urnbellifera eliminated one cause of death but mortality of adult petrels continued at an unsustainable rate as the result of predation by the Pied Currawong Strepera graculina. Hunting and feeding behaviour of the Pied Currawongs were observed, including holding fast a petrel carcass while ripping flesh from the skeleton. Mortality of Gould's Petrels subsided immediately following the destruction of Pied Currawong nests and nestlings. Subsequent recurrences of predation were correlated with additional nesting attempts by Pied Currawongs but declined substantially following the instigation of a control program for Pied Currawongs on Cabbage Tree Island. Pied Currawongs take the eggs and nestlings of many species of birds, but losses of nesting adults or the decline of a seabird have not been attributed previously to currawong predation.

The aim of this study was to describe the roosts of Nyctophilus bifax in littoral rainforest in Iluka Nature Reserve on the north coast of New South Wales. Radio-telemetry was used to track 17 bats in November 1988 (lactation season) and 11 in May 1989 (mating season) to 87 roosts in 49 trees within the littoral rainforest. The bats frequently changed roosts, which were clustered within a small area. During November, lactating females moved twins between diurnal roosts and some carried twins while foraging. Twins represented a load of up to 95% of their mother's bodyweight. Bats roosted communally in foliage and tree hollows, beneath peeling bark, among epiphytes, and between strangler figs and host trees. Hollows were used more frequently when bats were lactating, while the use of foliage roosts was greater during the mating season. Roosts were concentrated in four tree species, although a wide range of other tree species was used. Roost trees used in November were taller (17 m) than those used in May (8.2 m), and reflect selection of Syzygium leuhmannii and Acmena hemilampra, both trees of the forest interior. The converse applied for selection of Cupaniopsis anacardioides, a small tree of the littoral zone, in May. These results identify the need for conserving a diversity of roosts for this species of bat.

Conservationists are continually seeking new strategies to reverse population declines and safeguard against species extinctions. Here we evaluate the potential efficacy of a recently proposed approach to offset a major anthropogenic threat to many marine vertebrates: incidental bycatch in commercial fisheries operations. This new approach, compensatory mitigation for marine bycatch (CMMB), is conceived as a way to replace or reduce mandated restrictions on fishing activities with compensatory activities (e.g., removal of introduced predators from islands) funded by levies placed on fishers. While efforts are underway to bring CMMB into policy discussions, to date there has not been a detailed evaluation of CMMB's potential as a conservation tool, and in particular, a list of necessary and sufficient criteria that CMMB must meet to be an effective conservation strategy. Here we present a list of criteria to assess CMMB that are tied to critical ecological aspects of the species targeted for conservation, the range of possible mitigation activities, and the multi-species impact of fisheries bycatch. We conclude that, overall, CMMB has little potential for benefit and a substantial potential for harm if implemented to solve most fisheries bycatch problems. In particular, CMMB is likely to be effective only when applied to short-lived and highly-fecund species (not the characteristics of most bycatch-impacted species) and to fisheries that take few non-target species, and especially few non-seabird species (not the characteristics of most fisheries). Thus, CMMB appears to have limited application and should only be implemented after rigorous appraisal on a case-specific basis; otherwise it has the potential to accelerate declines of marine species currently threatened by fisheries bycatch.

Understanding seed germination and seedling recruitment is important for managing long-lived plant species, particularly palms that are transplanted from the wild and where regeneration is suppressed by seed predators and exotic herbivores. Seed viability, the timing of germination, and the factors influencing germination were investigated for the cabbage tree palm, Livistona australis (R.Br.) Mart. Greenhouse studies were combined with in situ experiments conducted on the Australian mainland and on a nearby mammal-free island. Under greenhouse conditions, >90% of seed germinated within 4 months. In the field, burial rather than surface sowing of seed increased germination success. Seed without mesocarp and in sunlight had increased germination when compared with fruits in shade on the island, whereas neither presence/absence of mesocarp or light levels had any effect on the mainland. Germination success was substantially lower on the mainland, primarily because of high seed predation from the native bush rat, Rattus fuscipes. When caged to exclude vertebrates, 44% of seed were damaged over time by pathogens and invertebrates, with losses greater in sunlight than in shade. Results from the present study indicate that freshly buried seed with the mesocarp removed would have the greatest potential success in promoting the restoration of L. australis at degraded sites.

On Australian semiarid floodplains, large herbivores such as kangaroos have a role in the cycling of energy (carbon) through the mechanism of feeding and defaecation of vegetative material. The degree to which kangaroos are vectors of energy within this system is not fully understood. This study describes the stable carbon isotope signature of floodplain plants and kangaroo scats at two close study sites. Kangaroos were found to deposit scats that mirrored the forage composition at each particular feeding site. Scats were 3.94‰ higher in δ13C values at the site where C4 grasses were available, indicating that this grass contributed ~25–30% of the diet of these kangaroos. The difference in diet due to the relative availability of C3 and C4 forage, detectable in the carbon stable isotope signature of scats, is used to demonstrate that kangaroos are recycling and redistributing energy locally, rather than transporting it more broadly across the floodplain.

Summary The ‘Critically Endangered’ Fiji Petrel Pseudobulweria macgillivrayi is believed to breed only on the island of Gau, Fiji, but its nesting grounds have yet to be located. Until a bird was captured in 1984, the species was known from only a single museum specimen (collected in 1855), one sighting on land (in 1965) and four unverified sightings at sea (1964–65). Local knowledge of the Fiji Petrel is restricted to a few lines of a traditional lullaby. In this paper we collate and review all records of the species, and examine all known attempts to locate nesting sites. Since 1985 there have been 15 reports of sightings on land and six at sea. Two additional specimens, both pre-breeding adults, have been obtained. Although our knowledge of this elusive species is slowly increasing, the timing of the breeding cycle remains uncertain, making the search for nesting sites particularly challenging. Known potential threats on Gau include predation by introduced cats, rats and pigs. We detail recent conservation efforts and prescribe some new initiatives, including the use of sniffer dogs. Locating the nesting grounds of the Fiji Petrel remains the prime conservation priority for this species.

Procellariiformes (albatrosses and petrels) must accumulate substantial energy reserves to sustain them while incubating their single egg. They then produce a chick that is often more than 130% of their own body mass. Thus, despite the variable nature of resource availability in the marine environment, successful reproduction requires a considerable increase in foraging rates. Birds that are better foragers are, therefore, likely to be better parents. As surrogates of foraging ability, we assessed two parental traits that are separated temporally over the breeding season, body condition during incubation and provisioning performance, in Gould’s petrel (Pterodroma leucoptera). Although parental condition did not influence hatching success, we found significant positive correlations between the average body condition of a breeding pair and both the growth rate of chicks (g day–1) and the body condition of chicks at peak mass. Provisioning rate also correlated positively with chick condition. Chick condition was positively correlated with haemoglobin concentration [Hb] at peak mass, which was positively correlated with [Hb] at fledging. Because the probability of survival after fledging may be influenced by chick body condition and [Hb], the ability of parents to acquire additional resources for breeding is likely to be an important determinant of reproductive success.

An isolated population of malleefowl (Leipoa ocellata) at Yalgogrin in New South Wales, Australia, was studied intensively between 1986–87 and 1998–99. During this period the population produced 124 clutches, comprising a total of 1705 eggs. The number of clutches per annum varied between 5 and 15. Eggs were laid between mid-August and mid-February, with 90% laid between the last week of September and the first week of January. The mean date of laying of the first egg of each clutch (±s.d.) was 21 September ± 13 days and the mean date of the last egg was 23 December ± 19 days. The mean duration of egg laying varied significantly between years (range 70–117 days) and was negatively correlated with the daily maximum ambient temperature in December. Cool temperatures and rain in early summer prolonged the laying season. The mean interval between laying was 6.4 ± 1.1 days (range 3–12 days), with eggs laid at a faster rate during the first half of the laying period. Overall, mean clutch size was 14.1 ± 5.8 (range 1–28). Large clutches were the result of an extended period of laying rather than an increase in the rate of laying. Mean clutch size was greatest when laying extended into mid-February. The best predictor of clutch size was rainfall between May and December – the interval spanning both nest construction and egg laying. The mean volume of all measured eggs (n = 1362) was 162.1 ± 9.0 mL (range 99–200 mL). Egg volume varied during the laying period, with those eggs laid early or late in the breeding season being smaller. Eggs at Yalgogrin were, on average, 10.5% smaller than those recorded at nearby Pulletop.