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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.

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.

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.

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.

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.

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.

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.

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.

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.