The ACAP-listed and globally Near Threatened Grey Petrel Procellaria cinerea is a relatively little-studied species that breeds in winter on sub-Antarctic islands. On more than one such island it has been proven to be at risk to introduced feral cats or rodents.

On Australia’s now pest-free Macquarie Island Grey Petrels have been making a comeback since the last cats were killed. Annual monitoring continues as Penny Pascoe, Macquarie Island Wildlife Ranger reports in the latest issue of Macca’s on-line newsletter, This Week at Macquarie Island:

“Grey petrels are burrow-nesting seabirds, raising their chicks in burrows underground. While first reported breeding on Macquarie Island was in 1900, cats and rabbits had a detrimental effect on their numbers and breeding was not observed again for almost 100 years, until 1999. With cats and rabbits now successfully eradicated, grey petrel numbers are starting to rise, with over 120 breeding pairs found last season.

Grey petrel burrows tend to occur in clusters and known breeding sites are distributed around much of the island’s coastal slopes with the greatest concentration found on North Head, just north of the station. Over the past few months we have been trying to determine their breeding population size by searching for and checking burrows. This can be very cold work! It is nearly always wet and windy and sometimes there is snow. Finding a burrow amongst the dense tussock can be a challenge, but after a while you get an eye for the tell-tail signs like diggings, faeces and a distinct, musky smell.

Finding the burrow is just the first challenge; the next is to determine what is in it. This is usually a multi-step process. A torch is used first to peep inside. If nothing can be seen then a pocket camera is used at arm’s length to look in further. If this still does not reveal anything a GoPro on a stick is used to look even deeper. There is quite an art to keeping your fingers warm enough for them to work, but not so thickly swaddled in gloves that you cannot operate a camera anymore! It is always a great reward when you pull your muddy arm back out of a burrow, look at the photos you have taken and see a beautiful fluffy chick!”

Grey Petrel adult and chick in burrows on Maquarie Island, Photographs by Penny Pascoe

Read earlier ACAP Latest News reports on the fortunes of Macquarie’s Grey Petrels here.

John Cooper, ACAP Information Officer, 22 August 2017

UPDATE:  The stray dog, a "mixed-breed hound" was later euthanized (click here).

A stray dog has killed 33 Wedge-tailed Shearwaters Ardenna pacifica in a colony at the Pacific Missile Range Facility Barking Sands (PMRF) on the Hawaiian island of Kauai earlier this month.

Remains of the killed shearwaters were found near the facility’s beach cottage and recreational area on the morning of 7 August. Four adults found alive that were badly injured in the attack have been taken into captivity by Save Our Shearwaters of the Kauai Humane Society. One of these was euthanized because its fractures were so severe. Four orphaned chicks and two unhatched eggs are also under the care of Save Our Shearwaters. The chicks will be hand reared until they can fledge in November.

Photographs of rescued Wedge-tailed Shearwater chicks (and an egg) courtesy of Save Our Shearwaters, Kauai Humane Society

One of the collected eggs is being fostered by a pair of Wedge-tailed Shearwaters that had a non-viable egg. Staff members are monitoring whether that egg will hatch.

Paw prints and dog droppings were found in the vicinity of the remains; a free-ranging dog was found the next day and taken to the Kauai Humane Society. No reports of further shearwater killings have been reported since the capture of this stray animal.

The PMRF policy is for residents to leash and supervise pets at all times, and a fenced area exists to help protect shearwater breeding colonies within the facility. Burrows found outside the breeding areas are protected by placing a shielding tent over them to ensure they are not accidentally stepped on or crushed.

A Wedge-tailed Shearwater pair

Read more here.

There have a number of cases in recent years of free-ranging dogs killing Laysan Albatrosses Phoebastria immutabiis on Kauai.  Read ACAP Latest News' latest report and follow its links.

John Cooper, ACAP Information Officer, 21 August 2017, updated 23 August 2017

Hannah Froy (Institute of Evolutionary Biology, University of Edinburgh, Scotland, UK) and colleagues have published in the Journal of Animal Ecology on ageing effects in Black-browed Thalassarche melanophris, grey-headed T. chrysostoma and Wandering Diomedea exulans Albatrosses.

The paper’s abstract follows:

1. “Age-related variation in reproductive performance is ubiquitous in wild vertebrate populations and has important consequences for population and evolutionary dynamics.
2. The ageing trajectory is shaped by both within-individual processes, such as improvement and senescence, and the among-individual effects of selective appearance and disappearance. To date, few studies have compared the role of these different drivers among species or populations.
3. In this study, we use nearly 40 years of longitudinal monitoring data to contrast the within- and among-individual processes contributing to the reproductive ageing patterns in three albatross species (two biennial and one annual breeder) and test whether these can be explained by differences in life histories.
4. Early-life performance in all species increased with age and was predominantly influenced by within-individual improvements. However, reproductive senescence was detected in only two of the species. In the species exhibiting senescent declines, we also detected a terminal improvement in breeding success. This is suggestive of a trade-off between reproduction and survival, which was supported by evidence of selective disappearance of good breeders.
5. We demonstrate that comparisons of closely related species which differ in specific aspects of their life history can shed light on the ecological and evolutionary forces shaping variation in ageing patterns.“

Grey-headed Albatross at Bird island, photograph by Richard Phillips

Reference:

Froy, H., Lewis, S., Nussey, D.H., Wood, A.G. & Phillips, R.A. 2017. Contrasting drivers of reproductive ageing in albatrosses. Journal of Animal Ecology 86:1022–1032. DOI: 10.1111/1365-2656.12712.

John Cooper, ACAP information Officer, 18 August 2017

André Raine (Kaua‘i Endangered Seabird Recovery Project, Hanapēpē, Kaua‘i, Hawaii, USA) and colleagues have published in the journal The Condor: Ornithological Applications on population changes in globally Vulnerable Hawaiian Petrels Pterodroma sandwichensis and globally Endangered Newell's Shearwaters Puffinus newelli on the Hawaiian island of Kauai.

The paper’s abstract follows:

“The island of Kaua‘i, Hawaii, USA, holds a large breeding populations of the endangered Hawaiian Petrel (Pterodroma sandwichensis) and a majority of the world population of the threatened Newell's Shearwater (Puffinus newelli). We evaluated island-wide population trends of both species. For Newell's Shearwaters, we considered radar counts at 13 sites between 1993 and 2013 and annual island-wide tallies of fledglings retrieved after being grounded by light attraction in 1979–2015 (Save Our Shearwaters [SOS] program). For Hawaiian Petrels, we considered radar counts alone. Radar data indicated a 78% decline overall in numbers of Hawaiian Petrels (at an average rate of ∼6% per year) and a 94% decline overall in numbers of Newell's Shearwaters (at an average rate of ∼13% per year) during the survey period. Most (92%) radar sites showed significant declines of Newell's Shearwaters across the entire survey period, as did 62% of sites for Hawaiian Petrels. The SOS recovery effort collected 30,522 Newell's Shearwater fledglings between 1979 and 2015. When we compared this dataset in pre- and post-Hurricane Iniki (September 1992) periods, we found a significant downward trend after Hurricane Iniki, similar to the trend seen in the radar data. The large-scale declines found in this study are not surprising, considering the significant threats facing both species on Kaua‘i, which include powerline collisions, light attraction, introduced predators, and habitat modification—threats which were potentially exacerbated after Hurricane Iniki. Improved conservation initiatives and an increased understanding of the various threats facing the 2 species are key to reversing these declines.”

Newell's Shearwater chick, photograph by André Raine

Reference:

Raine, A.F., Holmes, N.D., Travers, M., Cooper, B.A. & Day, R.H. 2017. Declining population trends of Hawaiian Petrel and Newell's Shearwater on the island of Kaua‘i, Hawaii, USA. The Condor: Ornithological Applications doi.org/10.1650/CONDOR-16-223.1.

http://www.bioone.org/doi/abs/10.1650/CONDOR-16-223.1

John Cooper, ACAP Information Officer, 17 August 2017