UPDATE - NO RESPITE

Attacks by House Mice on Marion Island's beleagured Wandering Albatross chicks continue, with the latest victim in the Macaroni Bay study colony photographed by island researcher Michelle Risi today.

Scalped! This month's victim, photograph by Michelle Risi, 12 August 2023

A Wandering Albatross chick on Marion Island shows clear signs of being attacked by mice; photograph by Michelle Risi

Marion Island’s seabirds are under attack. Predatory House Mice are ravaging their chicks, and even adults for some species. The Mouse-Free Marion (MFM) Project aims to rectify this situation and put the island back on the road to recovery. This will be done by a major campaign set to take place in winter 2025 when a fleet of helicopters will spread rodenticide bait over the whole island.

Scalped! A House Mouse feeds at night on the head of a defenceless Wandering Albatross chick on Marion Island in 2015; photograph by Stefan and Janine Schoombie

One of the most iconic seabirds that breeds on the island is the Wandering Albatross Diomedea exulans. Marion Island supports no less than a quarter of its world population, making it the most important breeding locality for this globally Vulnerable species. Despite its huge size, especially relative to a diminutive mouse, it is not safe from attacks that have led to severe wounding and eventual death of chicks, literally eaten alive while sitting on their nests. The first attacks on Wanderer chicks on Marion were recorded in 2003. Still photographs and video clips, some made at night, graphically illustrate the conservation problem (click here to access scientific publications on the mouse attacks).

Another view of the wounded chick, showing exposed flesh and bone on its rump; photograph by Michelle Risi

It is not unexpected then, but still worrying, to hear that attacks on Marion’s Wandering Albatross chicks are continuing, with the first observation this year being made on Midwinter’s Day (21 June) by island researchers Michelle Risi and Chris Jones from Nelson Mandela University’s Marine Apex Predator Research Unit. The post-guard chick had a wound on the rump leading to its downy flank becoming blood stained. The chick was in a long-term study colony (one of three on the island) centred above Macaroni Bay on the island’s east coast. Established in the early 1980s, all the nests in the study colonies are staked and mapped. Breeding adults are colour banded and followed through the long breeding season. This season 95 eggs were laid, but currently only 42 chicks remain. Chick mortalities due to mice have regularly reduced breeding success in this study colony, and it seems that the 2023 season will be no exception.

Before the attack: the chick on 6 June in good health; photograph by Michelle Risi

Photographed earlier on 6 June, the same chick then appeared to be in good health. A return visit on 29 June revealed the chick had succumbed and its corpse had likely been scavenged or it had been killed while in a moribund state by giant petrels Macronectes spp. and/or Subantarctic or Brown Skuas Catharacta antarctica. This disappointing outcome confirms the necessity and urgency of eradicating the island’s mice and encourages the MFM Project team to continue to work hard towards achieving this aim in two-year’s time.

With stake M11 marking the nest site as if a grave, all that remained of the chick on 29 June; photograph by Michelle Risi

With thanks to Michelle Risi, Marine Apex Predator Research Unit, Nelson Mandela University, South Africa.

John Cooper, Emeritus Information Officer, Agreement on the Conservation of Albatrosses and Petrels, 11 July 2023, updated 12 August 2023

NOTE: First published on the Mouse-Free Marion Project website on 04 July 2023

Antarctic Krill (pictured) is a keystone species in Antarctica and now have a 'World Day' in honour of their importance to the Southern Ocean

Today, 11 August, marks World Krill Day, and though they are small, these crustaceans deserve to be celebrated enormously as one of the unsung heroes of the planet.

Krill are a key species in the Antarctic and an important food source for many species of marine life in the Southern Ocean, including albatrosses and other ACAP-listed species. 

Threats to Antarctic Krill and the marine life dependent on it include: rising sea temperatures which are impacting the distribution of krill in the Antarctic, forcing populations southward to colder waters, and an increased interest in krill resources from commercial fisheries. 

Incidental deaths of albatrosses and petrels also occur in krill trawl fisheries when birds may collide with cables and become injured, or be dragged underwater when their wings become entangled around the warp; birds can also become entangled in nets during shooting and hauling. 

The re-establishment of the Working Group on Incidental Mortality Associated with Fishing (WG-IMAF) at last year’s CCAMLR meeting in Tasmania was welcomed by the Agreement. The WG-IMAF was originally created in response to concerns over the decline in albatross populations, and the potential for this to be exacerbated by interactions with CCAMLR fisheries and was reconvened in 2022 to review mitigation of incidental mortality in the krill trawl fishery. 

ACAP has been extended an ongoing invitation for an ACAP expert to participate in the WG-IMAF and will be in attendance at this year’s CCAMLR meeting taking place in October this year.

The establishment of Marine Protected Areas (MPAs) in Antarctic waters has been a decade-long pursuit for CCAMLR and is urged by Rod Downie, Chief Polar Adviser at WWF-UK, who said: "[But] changes in krill distribution and a growing interest from the fishing industry necessitates rapid action towards a network of marine protected areas incorporating krill habitat to support biodiversity and climate stability. We need to work with nature, not against it, in the fight against climate change.”

11 August 2023

 A White-chinned Petrel on a South Atlantic island, photograph by Andy Wood

UPDATE:  Prior to a planned eradiction effort in a few years time, control of feral cats around breeding burrows is proposed, "as well as habitat restoration which could involve tussac planting or creating artificial burrows" (click here).

Vulnerable White-chinned Petrels Procellaria aequinoctialis have suffered a total breeding failure in the 2022/23 summer on New Island in the Falkland Islands/Islas Malvinas*, as reported by the New Island Restoration Project on its Facebook page. “There used to be 30-33 pairs of White-chinned Petrels breeding on New Island. But in a February survey, instead of burrows filled with fluffy chicks, they were all empty. Camera traps reveal invasive predators, cats, rats, and mice using the burrows.” Watch a short video of rodents and a cat at burrow entrances.

However, better days for this beleaguered population may be ahead as the project is working towards eliminating all four species of introduced mammals on the island (click here). Watch also a six-minute video announcing the project.

As well as White-chinned Petrels, New Island also supports a breeding population of Black-browed Albatrosses Thalassarche melanophris, photograph by Deborah Pardo

The Project writes on its website page “Over the course of the next two winters, we will investigate the best course of action for a possible future removal of the invasive species. This will involve trialing non-toxic bait to better understand take-up rates from both target and non-target species and looking at the most effective ways to safeguard native species. We’ll also bolster biosecurity to reduce the risk of new invasive species establishing and causing harm.”

White-chinned Petrels are rare in the Falkland Islands/Islas Malvinas*, with breeding only known from three islands; New Island holds the bulk of the total population, estimated in a 2007 publication as being of a minimum of 55 pairs.

References:

Catry, P., Silva, M.C., MacKay, S., Campos, A., Masello, J., Quillfeldt, P. & Strange, I.J. 2007.  Can thin-billed prions Pachyptila belcheri breed successfully on an island with introduced rats, mice and cats? The case of New Island, Falkland Islands. Polar Biology 30: 391–394.

Matias, R & Catry, P. 2008. The diet of feral cats at New Island, Falkland Islands, and impact on breeding seabirds. Polar Biology 31: 609-616.

Quillfeldt, P., Schenk, I., McGill, R.A.R., Strange, I.J., Masello, J.F., Gladbach, A., Roesch, V. & Furness, R.W. 2008. Introduced99 mammals coexist with seabirds at New Island, Falkland Islands: abundance, habitat preferences, and stable isotope analysis of diet. Polar Biology 31: 333-349.

Reid, T., Lecoq, M. & Catry, P. 2007. The White-chinned Petrel Procellaria aequinoctialis population of the Falkland Islands. Marine Ornithology 35: 57-60.

John Cooper, Emeritus Information Officer, Agreement on the Conservation of Albatrosses and Petrels, 10 August 2023, updated 12 August 2023

*A dispute exists between the Governments of Argentina and the United Kingdom of Great Britain and Northern Ireland concerning sovereignty over the Falkland Islands (Islas Malvinas), South Georgia and the South Sandwich Islands (Islas Georgias del Sur y Islas Sandwich del Sur) and the surrounding maritime areas.

 A Grey-headed Albatross of the South Atlantic; photo by Richard Phillips

The British Antarctic Survey (BAS) has advertised for two Seabird Surveyors to join the Ecosystems team and carry out a field survey of Black-browed and Grey-headed Albatrosses in the South Atlantic. Surveyors will additionally, evaluate the current status and trends of the two species (along with Wandering Albatrosses from a separate survey) and update Conservation Action Plans. 

These specific populations of Black-browed, Grey-headed and Wandering Albatrosses are ACAP Priority Populations (declining at more than 3% per year, hold more than 10% of the global population, and are at risk from fisheries), therefore findings from the survey will be critical to their ongoing conservation management. 

This new research intends to provide an update on earlier an earlier study, published in the journal Polar Biology in 2017, on population trends of these species. 

The Postholder roles are described in the advertisement as follows: 

Postholder 1 (7-month contract) will be expected to:

• photograph selected colonies during the field survey (mid Nov. to mid Dec. 2023)
• count albatrosses in images
• compare counts from Unoccupied Aerial Vehicle (UAV or drone) imagery with those from photos
• generate correction factors from data on breeding failure rates and diurnal attendance patterns collected
• determine current breeding population sizes and long-term trends
• write a manuscript for a peer-reviewed scientific journal, and: 
• update Conservation Action Plans. 

Postholder 2 (3-month contract) will:

• conduct a series of UAV-based aerial surveys of the colonies, and;
• count the albatrosses in the resulting UAV imagery.

The deadline for applications is Wednesday, 16 August 2023.

For more information, and to apply, please visit the British Antarctic Survey website, here.

09 August 2023