Australia’s Lord Howe Island is infested with rats and plans have been in place since 2001 to rid the island of them, so as to leave its petrel and shearwater populations (and other wildlife) in peace (click here).

In 2012 the Australian Federal and News South Wales Governments announced that funding of AUD 4.5 million from each government had been made available for the eradication to go ahead, then set for 2015.  In the event this did not happen due to divisions within the island community that slowed the process.

The latest news is that the Lord Howe Island Board has now applied to the Australian Government Minister for the Environment for approval under the Environment Protection and Biodiversity Conservation Act to undertake the eradication, currently intended to take place in the austral winter of 2017 by aerial poison bait drop.

In terms of the Act a Public Environment Report has first to be produced, with a draft now open for public comment until 2 December.  ACAP Latest News will report on the outcome once further news is to hand.

Flesh-footed (left) and Wedge-tailed Shearwaters, photographs by Barry Baker and Alan Burger  

Two shearwaters that breed on the island, the Flesh-footed Puffinus carneipes and Wedge-tailed P. pacificus, have been identified as potential candidates for listing within the Albatross and Petrel Agreement.  The Lord Howe Island Group, 14.6 km² and approximately 700 km north-east of Sydney in the South Pacific, has been a World Heritage Site since 1982.  Black Rats Rattus rattus first arrived on the island via a shipwreck in 1918 and have wreaked havoc ever since for nearly a hundred years.  House Mouse Mus musculus are also present and will be targeted along with the rats

With thanks to Jonathon Barrington for information.

John Cooper, ACAP Information Officer, 04 November 2016

Sebastián Jiménez (Laboratorio de Recursos Pelágicos, Dirección Nacional de Recursos Acuáticos, Montevideo, Uruguay) and colleagues have published in the journal Antarctic Science on sexual bias in Southern Diomedea epomophora and Northern D. sanfordi Royal Albatrosses caught on longlines in Uruguayan waters.

The paper’s abstract follows

“Bycatch in longline fisheries is a major contributor to the global decline of albatrosses.  Sexual segregation at sea often leads to unequal overlap with different fisheries, resulting in sex-biased bycatch, exacerbating the impact on a population level.  In great albatrosses (Diomedea spp.), males (the larger sex) tend to spend more time at higher latitudes than females, attributed to competitive exclusion or differences in flight performance mediated by the pronounced sexual size dimorphism (SSD).  Consequently, larger numbers of females are bycaught in pelagic longline fisheries in subtropical and temperate areas.  Although this has been shown for Diomedea exulans, it has not been confirmed for all great albatross species.  Here we examined the degree of SSD and developed discriminant functions to determine species and sex in D. epomophora and D. sanfordi species that are often killed in several fisheries in the Southern Hemisphere.  Based on a large sample of albatrosses bycaught off Uruguay, both species showed substantial SSD.  Discriminant functions assigned species and sex to otherwise indeterminate individuals with 90–100% accuracy.  Based on all birds identified (n = 128), bycatch in the pelagic longline fishery was female-biased, indicating sexual segregation at sea.  The discriminant functions presented enable species and sex to be identified, providing critical data for future bycatch assessments.”

Northern Royal Albatross at sea, photograph  by  Aleks Terauds

With thanks to Sebastián Jiménez.

Reference:

Jiménez, S., Domingo, A., Brazeiro, A., Defeo, O., Abreu, M., Forselledo, R. & Phillips, R.A. 2016.  Sexual size dimorphism, spatial segregation and sex-biased bycatch of southern and northern royal albatrosses in pelagic longline fisheries.  Antarctic Science doi:10.1017/S0954102016000493.

John Cooper, ACAP Information Officer, 03 November 2016

Eric Vanderwerf and Lindsay Young (Pacific Rim Conservation) write about aspects of the population biology of ACAP-listed Laysan Albatrosses Phoebastria immutabilis in the Kaena Point Natural Area Reserve and Kuaokala Game Management Area on the Hawaiian island of Oahu in the journal The Condor – Ornithological Applications.

The paper’s abstract follows:

“Understanding population dynamics and determining conservation priorities in long-lived species with delayed breeding often is hampered by lack of information about younger age classes.  Obtaining accurate estimates of juvenile survival and recruitment can be difficult because young individuals are infrequently observed.  We used mark– recapture models to estimate age-specific survival, recruitment, population size, and encounter probability of Laysan Albatrosses (Phoebastria immutabilis) using a 14-yr dataset from Oahu, Hawaii, USA.  We also measured the long-term effect of avian pox virus (Poxvirus avium) on the survival and recruitment of albatrosses infected as nestlings.  Survival of juvenile albatrosses during the first year after fledging was 0.757 6 0.042.  We were able to estimate juvenile survival, the first such estimate in any long-lived seabird, because our high search effort revealed that some birds began visiting the natal colony at the age of 1 yr.  The survival of prebreeders increased rapidly and reached a value in the second year (0.973 6 0.008) that was similar to the survival of breeding adults (0.973 6 0.017).  The average age of first return to the natal colony was 4.24 6 0.11 yr.  The average age at first breeding was 8.44 6 0.15 yr, with recruitment probability peaking at ages 9–10 yr and a single bird being recruited into the breeding population at the age of 4 yr.  Pox virus decreased survival in the first year by 4%–13% and decreased recruitment probability up to age 12 by 4%–26%, depending on the severity of infection.  The total size of the Laysan Albatross population on Oahu in 2015 was 555 birds, consisting of 270 active breeders, 231 prebreeders, and 54 birds that likely skipped breeding that year.  The number of prebreeders constituted an average of 44% of the total population.  These demographic estimates will be useful for population modeling exercises involving various threat and management scenarios, and for examining environmental factors that influence demography.”

A Laysan Albatross pair with their chick at Kaena Point, photograph by Lindsay Young 

Reference:

VanderWerf, E.A. & Young, L.C. 2016.  Juvenile survival, recruitment, population size, and effects of avian pox virus in Laysan Albatross (Phoebastria immutabilis) on Oahu, Hawaii, USA.  Condor 118: 804–814.

John Cooper, ACAP Information Officer, 02 November 2016

The third in the series of Island Invasives Conferences will be held in the Dalhousie Building, University of Dundee, Dundee, Scotland over the week of 10-14 July 2017, organized by the South Georgia Heritage Trust and the University of Dundee.

The conference will follow on from two previous conferences held in Auckland, New Zealand; the most recent in January 2010.  It will be the first meeting in the series to be held in the Northern Hemisphere.

Registration and abstract (for both orals and posters) submission is now open.  Early-bird registration fees, saving UK£100 on the normal rate, will in principle be available until 30 April 2017. However, the conference lecture theatre holds 350 people, and numbers will likely be capped at this level, so it would be wise to sign up soon.  Presenting authors should register for the conference before submitting their abstracts (go to www.islandinvasives2017.com).

The World Conservation Union (IUCN) has offered to publish the proceedings of this conference, as it did for the others in the series.  The Chair of the Conference Committee is Tony Martin, Professor of Animal Conservation, University of Dundee.

ACAP has produced guidelines for the eradication of introduced mammals from breeding sites of ACAP-listed seabirds.  ACAP Latest News regularly reports on the successes, efforts and plans to rid islands in the Southern Ocean of their alien mammals, such as cats, mice, pigs, rabbits, Reindeer and rats, that impact upon albatrosses and petrels.

Read an earlier ACAP Latest News item on the conference.

With thanks to Tony Martin for information.

Selected Literature:

Phillips, R.A. undated.  Guidelines for Eradication of Introduced Mammals from Breeding Sites of ACAP-listed Seabirds.  ACAP Conservation Guideline.  9 pp.

Veitch, C.R. & Clout, M.N. (Eds) 2002. Turning the Tide: the Eradication of Invasive Species.  Proceedings of the International Conference on Eradication of Island Invasives.  Gland & Cambridge: IUCN SSC Invasive Species Specialist Group.  414 pp.

Veitch, C.R., Clout, M.N. & Towns, D.R. (Eds) 2011.  Island Invasives: Eradication and Management.  Proceedings of the International Conference on Island Invasives.  Gland: World Conservation Union & Auckland: Centre for Biodiversity and Biosecurity.  542 pp.

John Cooper, ACAP Information Officer, 01 November 2016