Amsterdam Albatross at sea: a southern Indian Ocean specialty.  Artwork by Birgit Bührlé and photograph by Kirk Zufelt

Adrien Chaigne (Centre d’Etudes Biologiques de Chizé, Villiers en Bois, France) and colleagues have published a technical report that analyses four decades (1978-2020) of at-sea surveys of 71  species of seabirds in the Southern Indian Ocean.

The report’s executive summary follows:

“Seabirds are conspicuous and important marine predators. They mostly forage on a diversity of zooplankton (copepods, euphausiids, amphipods) and nekton (squid and fish) prey. Because of their position in the trophic web, high energy requirements, mobility and longevity, these top marine predators can be used as indicators of the spatial variability of marine ecosystem functions and dynamics. We present here distribution maps of resident and migratory seabirds observed in two regions of the Southern Indian Ocean.

The present Atlas focuses on seabird's distribution in the Southern Indian Ocean using a unique long-term dataset (1978-2020) of at-sea observations made repeatedly over two time periods separated by 10 years to examine spatial and seasonal variation in seabird abundance and occurrence at a large spatial scale. Cruises encompassed a 30° latitudinal gradient through tropical, subtropical, subantarctic and Antarctic waters of the Southern Indian Ocean, allowing to explore the distribution of 71 seabird species (or pooled species). This is the first comprehensive summary of information on how some species or communities of seabirds of the Southern Indian Ocean use the habitats of this immense area. The present Atlas aims (1) to summarize the information on the occurrence and abundance of subantarctic and Antarctic seabirds over the period 1978-2020, according to season (austral summer versus austral winter) in two distinct geographical areas in the Southern Indian Ocean (western and eastern areas), and (2) to quantify the species diversity using diverse metrics.

The produced maps provide insights on biogeographic affinities, habitat associations, and "hotspots" of biodiversity and potential predator-prey dynamics. Identifying hotspots is potentially valuable in the design of offshore marine protected area networks. Within the study regions, we found apparent hotspots in subantarctic and Antarctic waters, especially in the vicinity of subantarctic islands. We observed strong seasonal changes in the distribution and abundance of seabirds, which alters the relative importance of these hotspots. The value of hotspots for the protection of these far-ranging pelagic species deserves further study.”

With thanks to Karine Delord.

Reference:

Chaigne, A., Delord, K., Mansoux, B., Bost, C.-A., Weimerskirch, H. & Barbraud, C. 2024.  Seabird Distribution in the Southern Indian Ocean: Four Decades of at sea Surveys.  CEBC-CNRS Marine Top Predators Team.  203 pp.

13 November 2024

The ACAP Species Infographic series is designed to help inform the general public, including school learners, of the threats faced by albatrosses and what is being and can be done to combat them. They serve to complement the more detailed and referenced ACAP Species Assessments, the concise and illustrated ACAP Species Summaries and the ACAP Photo Essay series. To date, 17 species infographics (out of the 31 ACAP-listed species) have been produced, the latest being for the Vulnerable White-chinned Petrel Procellaria aequinoctialis, recently released in English.

Versions for the White-chinned Petrel are now available in the other two ACAP official languages, French and Spanish, and also in Portuguese.  The last version reflects that the species visits the waters of Brazil (a Party to the Agreement).  Previously, Portuguese versions have been was produced for the Critically Endangered Tristan Albatross Diomedea dabbeneena and for the Black-browed Albatross Thalassarche melanophris.  A few more ACAP-listed species that regularly visit Brazilian waters will also have infographics produced in Portuguese.

The infographics produced to date may be freely downloaded at a high resolution to allow for printing professionally in two poster sizes (approximately A2 and A3).  English and Portuguese language versions of infographics are available to download here, whilst French and Spanish versions can be found in their respective language menus for the website under Infographies sur les espèces and Infographía sobres las especies.

Please note they are only being made available for personal use or when engaging in activities that will aid in drawing attention to the conservation crisis faced by the world’s albatrosses and petrels – when ACAP will be pleased to receive a mention.

The infographics are created by Thai illustrator Namasri ‘Namo’ Niumim from Bangkok.  With thanks to ‘Pep’ Arcos, Karine Delord and Patricia Serafini for their careful checking of texts in their home languages.

12 November 2024

 A Chatham Albatross; photo by Ross Wheeler

BirdLife’s Seabird Tracking Database (SBTD), a pioneering online data resource, is celebrating 20 years of collaboration for marine conservation.

From identifying critical habitats for seabirds, to being instrumental in mapping seabird interactions with fisheries, the Seabird Tracking Database has been central to the success of many marine conservation initiatives. 

To mark this significant milestone, a new study highlighting the achievements of the SBTD has been published open access in the journal, Biological Conservation. 

Ana Carneiro, lead author of the paper and Marine Science Manager at BirdLife International said: “The Seabird Tracking Database is a testament to the remarkable global collaboration among seabird scientists. Thanks to their willingness to share data, the STDB has not only deepened our scientific understanding of seabird ecology but has also driven tangible conservation outcomes, helping to protect threatened seabird populations worldwide.”

With its approximately 43 million location records and 55,000 tracks from 168 seabird species in 55 countries, the SBTD has been an instrumental resource for scientists, researchers and policymakers in their efforts to conserving one of the most threatened groups of vertebrates in the world.

However, gaps remain, particularly in tracking non-breeding adults and juveniles, and from underrepresented regions like the Pacific archipelagos, south of the Indian Ocean, and along species-rich coastlines. Addressing these gaps is the next phase for the SBTD which aims to expand species coverage and strengthen collaboration with other databases and initiatives. 

As seabirds face mounting challenges, including emerging threats such as offshore wind farms and the expansion of mesopelagic fishing, the STDB remains a vital tool in the conservation of seabirds.

Read BirdLife’s blog post on this significant milestone, or find the open access paper, The BirdLife Seabird Tracking Database: 20 years of collaboration for marine conservation, in the journal, Biological Conservation.

11 November 2024

Ground bait station sites on St Agnes and connected Gugh Islands during the rodent eradication operation

St Agnes is one five inhabited islands in the United Kingdom’s Isles of Scilly.  Following the eradication of Norway Rats Rattus norvegicus by a ground-baiting campaign a decade ago, both Manx Shearwaters Puffinus puffinus and European Storm Petrels Hydrobates pelagicus have been recorded breeding, signalling a successful operation (click here).  But this is not the end of the story.  It is necessary to put and keep in place best-practice biosecurity measures at points of entry that will greatly reduce the risk of reintroductions – and continue to keep a look out for signs of rodents elsewhere on the island.  A recent report from St Agnes nicely illustrates the problem as repeated here.

Manx Shearwater chick at its burrow entrance on St Agnes, photograph by Jaclyn Pearson

“Conservationists on an island 28 miles off the UK mainland are concerned after signs there may may be a mouse there, potentially putting a colony of seabirds at risk.  Mice and rats have been eradicated from St Agnes in the Isles of Scilly, as part of measures to protect its nationally significant population of storm petrels.  The Isles of Scilly Wildlife Trust said “probable” signs of a mouse including droppings and urine had been spotted, and suspects the creature was brought in within some animal feed.

The trust has been running a successful program with the RSPB and others to get rid of rodents on the islands for the past decade, which has led to the petrel population "bouncing back.  Tony Whitehead, from the RSPB, said it had a "very well worked out response" which involved putting rodent poison in traps across the island and "then keep checking the traps".

He said if "mice do get a hold on the island" they would be likely to eat the eggs of birds like storms petrels and Manx shearwaters, putting populations at risk. Mr Whitehead said a member of the community had spotted the mouse droppings last Thursday.

The residents of the island have been brilliant and hugely supportive.  The wildlife trust said signs had been put up across St Agnes to warn parents of young children and dog owners about traps.”

Read earlier  articles in ACAP Latest News on the rat eradication operation on the Isles of Scilly.

With thanks to Anton Wolfaardt, Mouse-Free Marion Project.

John Cooper, Emeritus Information Officer, Agreement on the Conservation of Albatrosses and Petrels, 11 November 2024