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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.

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).

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.

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.

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 ).

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.

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.

Nesting activity of a population of malleefowl (Leipoa ocellata), isolated within a small mallee remnant in central New South Wales, was monitored annually between the summers of 1986–87 and 1998–99. A total of 148 nesting events was recorded. Only once was a new mound constructed rather than an old one reworked. Birds began and finished work on the mound progressively later each month (October to January). Nest-site fidelity was highly variable; some pairs persisted with the same mound for up to nine years while others relocated between a cluster of two, three or four mounds. Males displayed greater nest-site fidelity than females. After the loss of a partner, males tended to continue to use mounds they had used previously whereas females often relocated to a new mound. All individuals were monogamous. Pair bonds were maintained for life but, following the death of a partner, new bonds were quickly established with another unattached individual. Established pairs occasionally failed to breed, all such failures being coincident with years of low rainfall. Pairs that did not breed generally began construction of a nest but failed to complete the task. As far as can be ascertained, unpaired birds did not construct nests. The malleefowl population was characterised by a rapid turnover of breeding individuals, a high rate of adult mortality and a lesser rate of recruitment. The maximum longevity recorded for breeding adults was 12 years; average longevity was 7.5 years. Twenty-five adults were lost from the breeding population over a period of 9 years; meanwhile, 14 birds entered the breeding population. Thus, the ratio of adult mortality to recruitment was 1.79 : 1.00. Between 1986–87 and 1997–98 the population declined from at least 32 breeding adults to 14, at an average exponential rate of decrease of 0.075. Large population decreases were coincident with years of low rainfall. This population of malleefowl is predicted to become extinct by 2008.

The effectiveness of localised, high-intensity fox baiting in reducing the incidence of fox predation was examined after captive-reared malleefowl were released and their survival monitored. Malleefowl released into baited areas survived longer than those released into nearby areas that had not been baited. Survival in both baited and non-baited areas was greater than that prior to any fox control. Of those malleefowl released, 29% were still alive three months later, whereas prior to fox control almost all were killed by foxes within a month of release. Despite the improvement in survival of malleefowl, fox predation remained the primary cause of malleefowl mortality. The number of baits taken by foxes indicated a large fox population and a high level of reinfestation. A more widespread, but less intensive, regime of baiting failed to further enhance the survival of malleefowl. Malleefowl were also particularly vulnerable to predation by raptors in habitats where the mallee was interspersed with areas of open woodland, and where the understorey was sparse. Fox baiting will need to be frequent, intensive and widespread to reduce fox density to levels where predation no longer threatens the survival or recovery of malleefowl populations.

The only population of Gould's Petrel Pterodroma leucoptera leucoptera has declined substantially during the last few decades. Adult mortality has been high, and has exceeded potential recruitment. Breeding success has been low. Entanglement in the sticky fruits of the Birdlime Tree Pisonia umbellifera and predation by Pied Currawongs Strepera graculina and Australian Ravens Corvus coronoides have been the major causes of petrel mortality on land. Experimental management actions aimed at ameliorating these threats were implemented, and their efficacy assessed. The removal of Pisonia and the control of avian predators dramatically lessened the mortality of Gould's Petrels ashore on Cabbage Tree Island. Instigation of these management actions in 1993 was coincident with a 68% rise in the number of birds brooding eggs in mid-December. Further small increases in the breeding population occurred in subsequent years. Management of the colony was also coincident with a substantial increase in breeding success (up from 25% to 45%). Breeding success increased to 59% in the 1994?95 season, but declined to 26% during 1995?96. Prior to management of the colony, an average of 30 birds fledged per annum (range 23?40; n= 4); after management, this rose to 167 per annum (range 105?233; n= 3). Management of the colony appears the most likely cause of this turnaround, but the possibility of it being due to extraneous factors such as weather or oceanographic perturbations cannot be excluded. The threats posed by Pisonia umbellifera and avian predators were, together, sufficient to account for the decline of Gould's Petrel. The demonstration that these two threatening processes can be ameliorated successfully suggests a high potential for recovery of the species.

Gould's petrel, Pterodroma leucoptera leucoptera, breeds only on Cabbage Tree Island, New South Wales. Annual surveys to estimate the size of the breeding population and the reproductive output were conducted between 1989 and 1992. Annual estimates of the total number of pairs breeding in the two gullies containing the main population were between 122 +/- 20 (s.e.) and 202 +/- 26. Breeding success was less than 20% between 1989 and 1991, but rose to 24.7% in 1992. This marginal improvement may be the result of management action undertaken to reduce mortality of breeding adults and fledglings. The total population is estimated to have declined from 2004 (95% confidence limits: 1464,3185) in 1970 to 1479 (1250,1815) in 1992, a decline of 26% in 22 years. The reasons for this decline are unclear.

Loss, fragmentation and degradation of mallee habitat within the New South Wales wheat-belt have caused a marked decline in the range and local abundance of malleefowl, Leipoa ocellata. Small disjunct populations of malleefowl now occupy small isolated remnants of suitable habitat. and several of these populations have become locally extinct in recent times. Young captive-reared malleefowl(8-184 days old) were experimentally released in March and June 1988 into a 558-ha remnant of mallee vegetation. The remnant contained a small but declining population of rnalleefowl. From the first day after release, malleefowl were found dead, and mortality continued at a rapid rate until none remained alive. Of the 31 released, 16 (52%) were dead after 7 days, at least 22 (71%) were dead after 11 days, and none survived longer than 107 days. In all, 94% of malleefowl were killed by predators: 26-39% by raptors, and 55-68% by introduced predators, principally foxes, Vulpes vulpes. No improvement in survival was evident when malleefowl were given supplementary food. Relying principally on camouflage, young malleefowl have no effective defence or escape behaviour to evade ground-dwelling predators such as the fox. By imposing severe predation pressure on young malleefowl, foxes are likely to be curtailing recruitment into the breeding population. Such a situation must inevitably lead to the further localised extinction of small disjunct populations of malleefowl. Foxes are thus a major threat to the continuance of remnant populations of malleefowl within the wheat-belt of New South Wales.