Free from mice attacks: a healthy 2021/22 Tristan Albatross chick on Gough Island; photograph by Roel Daling, Gough Island Restoration Project

In the austral winter of 2021, the Gough Island Restoration Project (GIRP) attempted to rid Gough Island in the South Atlantic of its albatross-killing House Mice Mus musculus by an aerial drop of cereal pellets laced with a rodenticide.  However, in December that year the first signs of mice being still present on the island were reported.  Subsequent surveys have shown that mice remain widespread (but presumably still in low numbers) over the island (click here).  Despite this, the island’s seabirds have been breeding much more successfully this year.  According to GIRP’s Facebook page “in June the island reported no signs of mouse attacks on 2022’s [Critically Endangered] Tristan Albatross [Diomedea dabbenena] chicks, although in previous years wounded chicks have been seen from the start of April.”

A later GIRP Facebook report gives more detail: “Despite horrible weather on Gough our amazing team counted 1186 Tristan Albatross chicks from 1570 breeding pairs, which results in a breeding success of 75.5%.  This is more than twice as high as the average from 2004-2021.  The greatest increase came from areas in the north-western part of the island, which have historically had very poor breeding success.  The team counted 201 chicks at West Point (previous years 30-50) and 177 in Giant Petrel Valley (previous years 30-90).  This shows what their future could look like on a mouse-free Gough and hardens our resolve to return.”  Based on monthly surveys in study colonies, few of the chicks counted last month are expected to die before fledging, so is to be expected that most of the 1186 counted will successfully leave the island around year end.

“Breeding success of Tristan Albatrosses on Gough Island from 2004 to 2022.  The horizontal dashed line is the typical breeding success on predator-free islands that would be sufficient for an albatross population to maintain itself.  In 2022 [red dot] the Tristan Albatrosses on Gough exceeded this threshold for the first time since records began”, graph by the Gough Island Restoration Project

The ACAP-listed and Near Threatened Grey Petrel Procellaria cinerea also had a good year on Gough with a 75% breeding success, compared to a typical rate of 30% prior to the mouse eradication attempt.  Because this burrowing petrel is a winter breeder, its chicks were at particular risk to mice, made hungry by seasonally diminishing food sources, such as grass seeds and invertebrates.  Likewise, two other largely winter breeders did well: “the Critically Endangered MacGillivray’s Prion [Pachyptila macgillivrayi] increased breeding success from an average of 6% with mice (including many years of 0% success) to 82% in 2022, whilst the Endangered Atlantic Petrel [Pterodroma incerta] had a 63% breeding success – more than double the previous year’s rate and well above average.  Gough Island is the global stronghold for both species”.

Not to be outdone, summer-breeding Endangered Atlantic Yellow-nosed Albatrosses Thalassarche chlororhynchos, known to be attacked by mice, achieved a 77% breeding success, and the equally Endangered Sooty Albatrosses Phoebetria fusca achieved 74%, figures comparable to those from mouse-free islands, and a marked increase to those of previous years.

The GIRP ends its blog on a cautionary note: “Mice are omnivores and will primarily eat seeds, plants, and invertebrates.  When mice become very abundant there is intense competition for food, and plant and invertebrate food sources can become depleted. Out of desperation hungry mice will then explore alternative food sources – and on Gough Island they started eating seabirds.  In 2022 the low numbers of mice (and hence low competition) meant they had plenty of other food to eat, and the seabirds were able to raise many chicks.  Unfortunately, we do not believe that this situation will persist.  We expect mice will become so abundant that they deplete their typical food sources and then start eating seabirds once again.   We do not know when this will happen, but as long as mice remain on Gough Island the future for seabirds is not secure. This year has shown us what seabirds can achieve when their chicks are not eaten by mice – and this gives us a determination to return to Gough in the future and remove the mice forever.”

Read more here and in the latest edition (No. 12) of GIRP’s newsletter Island Restoration News.

A PERSONAL NOTE:  With the essential help of many colleagues, I set up the long-term monitoring colonies of the three breeding albatross species and the Southern Giant Petrel Macronectes giganteus on Gough, staking nests and metal- and colour-banding incubating adults over my 18 enjoyable visits to the island (which included over-summering twice) from 1981 to 2013.  It is thus a great pleasure indeed to read of the high breeding successes achieved in the 2021/22 breeding season.  I can only hope they will continue for a few more years until a second eradication attempt finally rids Gough of its introduced House Mice.

John Cooper, ACAP News Correspondent, 15 November 2022

Map of the Baja California Pacific Islands, a seabird hotspot where breeding populations have been systematically monitored for almost two decades.

A study on population trends of seabirds on islands in the Mexican Pacific off the Baja California Peninsula has found that a holistic approach to conservation has had a cumulative positive effect on seabird populations including Albatross, Petrel and Shearwater species.  

The creation of protected areas, the eradication of invasive alien species, active restoration with social attraction techniques, and long-term monitoring were conservation and restoration measures enacted within the island group and identified in the research drivers behind the islands becoming a safe haven for seabirds.

The study, titled, “Population trends of seabirds in Mexican Islands at the California Current System” by Federico Sánchez (Grupo de Ecología y Conservación de Islas, Ensenada, Baja California, México) and colleagues has been published open access in the journal PLOS ONE.

The paper’s abstract follows:

“The Baja California Pacific Islands (BCPI) is a seabird hotspot in the southern California Current System supporting 129 seabird breeding populations of 23 species and over one million birds annually. These islands had a history of environmental degradation because of invasive alien species, human disturbance, and contaminants that caused the extirpation of 27 seabird populations. Most of the invasive mammals have been eradicated and colonies have been restored with social attraction techniques. We have recorded the number of breeding pairs annually for most of the colonies since 2008. To assess population trends, we analyzed these data and show results for 19 seabird species on ten island groups. The maximum number of breeding pairs for each nesting season was used to estimate the population growth rate (λ) for each species at every island colony. We performed a moving block bootstrap analysis to assess whether seabird breeding populations are increasing or decreasing. San Benito, Natividad, and San Jerónimo are the top three islands in terms of abundance of breeding pairs. The most widespread species is Cassin’s Auklet (Ptychoramphus aleuticus) with 14 colonies. Thirty-one populations of 14 species are significantly increasing while eleven populations of seven species are decreasing. We did not find statistical significance for 19 populations, however, 15 have λ>1 which suggest they are growing. Twelve of the 18 species for which we estimated a regional population trend are significantly increasing, including seven surface-nesting species: Brandt’s Cormorant (Phalacrocorax penicillatus), Brown Pelican (Pelecanus occidentalis), Caspian Tern (Hydroprogne caspia), Double-crested Cormorant (P. auritus), Elegant Tern (Thalasseus elegans), Laysan Albatross (Phoebastria immutabilis) and Western Gull (Larus occidentalis), and five burrow-nesting species: Ainley’s (Hydrobates cheimomnestes), Ashy (H. homochroa) and Townsend’s (H. socorroensis) Storm-Petrels, and Craveri’s (Synthliboramphus craveri) and Guadalupe (S. hypoleucus) Murrelets. The BCPI support between 400,000 and 1.4 million breeding individuals annually. Our results suggest that these islands support healthy and growing populations of seabirds that have shown to be resilient to extreme environmental conditions such as the “Blob”, and that such resilience has been strengthen from conservation and restoration actions such as the eradication of invasive mammals, social attraction techniques and island biosecurity.”

Reference:

Sánchez F. M., Guzmán Y.B., Mayoral E. R., Aguirre-Muñoz A., Koleff P., et al. (2022) Population trends of seabirds in Mexican Islands at the California Current System. PLOS ONE 17(10): e0258632. https://doi.org/10.1371/journal.pone.0258632

14 November 2022

The 50^th Annual Meeting of the Pacific Seabird Group (PSG) will take place February 15 – 17 2023 in in La Jolla, California, USA under the theme, “Boundary Currents in Borderless Oceans”.

PSG are calling for abstract submissions for the meeting, with topics inspired by the list below:

• Breeding Biology
• Climate Effects on Population Trends
• Climate Effects on Range and Migration
• Climate Effects on Behaviour
• Conservation and Restoration
• Contaminants and Marine Debris
• Extreme Events
• Fisheries Interactions
• Foraging Ecology
• Impact of Marine Plastics
• Integrated Studies of Seabirds Within Ecosystems
• Management and Policy
• Nonbreeding Biology
• Offshore Wind Impacts
• Population Biology
• Physiology
• Rodent Eradication
• Seabirds and Indigenous Cultures

Abstract submission will take place via Oxford Abstracts and will be accepted until 9 December 2022. Questions about abstract submissions can be directed to the PSG 2023 Scientific Program Chair atThis email address is being protected from spambots. You need JavaScript enabled to view it..

Travel awards are available through application to both North American (USA & Canada) and international students, as well as international scientists. Applications for travel awards close 30 November 2022 with successful applicants announced early December. For more information on travel awards, refer to the PSG Handbook or contactThis email address is being protected from spambots. You need JavaScript enabled to view it..

To register, submit an abstract or for further details about the event, head to the PSG 2023 Annual Meeting webpage.

11 November 2022

The Mouse-Free Marion Project’s campaign worked hard through social media with daily postings to Facebook and Instagram
A gam of juvenile Wandering Albatrosses displays on Marion Island; photograph by Tom Peschak

Last month the Mouse-Free Marion Project made it into the final round of the 2022 European Outdoor Conservation Association’s (EOCA) latest project funding vote.  Listed with three other short-listed projects in the ‘Wild Places’ Category, the MFM Project needed to win the most public votes in order to receive a requested 50 000 Euros towards the funding critical for its work to ensure the conservation of Marion Island’s seabirds that face the onslaught of introduced House Mice Mus musculus.

Regular social media postings kept the MFM Project campaign alive

What followed was a targeted campaign that saw the MFM Project receive widespread support from across South Africa and globally.  The project’s social media and email campaigns reached thousands of people and posts were shared by partner institutions, families, friends and project supporters, and talks were given to interested groups. The call to vote was shared by South African university research groups working across the marine space and in the sub-Antarctic and Antarctic regions.

EOCA has now announced the results of the Wild Places Category and out of the four short-listed candidates, the “Mouse-Free Marion: - Saving Marion Island’s Seabirds” has been informed it won with 45.1% of the 8121 votes cast.

The Mouse-Free Marion Project expresses its thanks to its many supporters
Wandering Albatrosses display on Marion Island; photograph by Sean Evans

The Mouse-Free Marion Project writes: “The support that the MFM Project received was incredible.  We thank each and every person who voted for Marion Island’s seabirds, whether it was sharing a social media post, forwarding an email or sending us an encouraging message.  This funding, although only a small part of what is needed to conduct the eradication of invasive mice on Marion Island, will help enormously towards reaching our funding goal.  We encourage those who would like to keep up with project progress to sign up to our newsletter and to follow our social media accounts.”

With thanks to Robyn Adams, Communications Officer, Mouse-Free Marion Project.

John Cooper, ACAP News Correspondent, 10 November 2022