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

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

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

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

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

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