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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.

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.

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 (

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.

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.