Laurie Maynard (Department of Biological Sciences, University of Manitoba, Winnipeg, Canada) and colleagues have published in the journal The Auk on responses of North Atlantic seabirds to supplementary feeding of fish offal at sea.

The paper’s abstract follows:

“While foraging, a predator can feed solitarily or in a group. The net energy gain of joining a group is predicted to vary with prey patch quality, species-specific prey capture behavior, and the size and species composition of the predator group. In coastal Newfoundland, Canada, capelin (Mallotus villosus), a key forage fish, migrates inshore to spawn during the summer, resulting in a dramatic shift in prey availability. During July–August 2015–2017, we examined the numerical and behavioral responses of procellarid (Great Shearwater [Ardenna gravis], Sooty Shearwater [A. grisea], Northern Fulmar [Fulmarus glacialis]), and gull species (Herring Gull [Larus argentatus], Great Black-backed Gull [L. marinus]) to fish offal under varying capelin availability as well as flock size and composition using an at-sea experiment on the northeast Newfoundland coast. The experiment consisted of providing offal every 30 s (10-min experimental period), along with 10-min control periods before and after. We recorded the species-specific number of birds on the water, the number of birds simultaneously attempting to capture offal, and the number of successful attempts (“foraging success”). The number of birds on the water was lower during high capelin availability for all species, except for Northern Fulmar. The number of conspecifics simultaneously attempting to capture offal increased with the number of conspecifics on the water, but plateaued at different numbers (4–17) for most species. The species-specific proportion of successful attempts (i.e. foraging success) varied with flock size and composition (i.e. number of conspecifics, heterospecifics, species). Foraging success of Herring Gulls and fulmars were moderately affected by flock size and composition, suggesting that they may be dominant competitors. Findings suggest that seabirds rely more heavily on supplemental food sources, such as fisheries discards and offal, when natural prey availability declines, potentially resulting in a higher risk of by-catch during fisheries activities as forage fish stocks decline.”

Great Shearwater at sea

Reference:

Maynard, L.D., Carvalho, P.C.& Davoren, G.K. 2019.  Seabirds vary responses to supplemental food under dynamic natural prey availability and feeding aggregation composition.  The Auk doi.org/10.1093/auk/ukz062.

John Cooper, ACAP Information Officer, 08 December 2019

Three sub-Antarctic island groups in the southern Indian Ocean belong to France, a Party to the Agreement on the Conservation of Albatrosses and Petrels.  These are the Crozets, Amsterdam and St Paul, and Kerguelen, all administered by the French Southern and Antarctic Territories (Terres Australes et Antarctiques Françaises - TAAF).  France supports research stations on Possession Island in the Crozet group, on Amsterdam and on Kerguelen.  At each researchers undertake monitoring and other studies of the islands’ breeding seabirds, including on a number of ACAP-listed albatrosses and petrels.

ACAP has reached out to marine ornithologists at the three research stations with requests that they make banners and photograph them in the field that emphasize the conservation crisis facing the world’s albatrosses and also draw attention to next year’s inaugural World Albatross Day.  ACAP Latest News has previously posted on banners from Amsterdam and Possession Islands, and is now pleased to announce a French hat-trick with photographs of a banner taken at two localities by Kerguelen’s ornithologists.  Aude Schreiber and Tobie Getti (Mission 69) undertake long-time monitoring of several bird and mammal species, including the ACAP-listed Black-browed Thalassarche melanophris and Wandering Diomedea exulans Albatrosses and Grey Petrel Procellaria cinerea, as well as several other species of burrowing petrels on Kerguelen.

From left: Anne Bontemps (bottom), Léa Dillard, David Gallien (centre), Aude Schreiber (top) and Tobie Getti display their banner behind a Wandering Albatross chick on the Prince de Galles Peninsula; photograph by Aude Schreiber

On the cliffs of the Canon des Sourcils noirs colony of Black-browed Albatrosses on the Jeanne d’Arc Peninsula.  From left: Tobie Getti, Aude Schreiber and Baptiste Camus; photograph by Marc Le Pape

The three French banners join others displayed on New Zealand, South African and UK islands in the Southern Ocean.  More are expected as albatross breeding seasons get underway.  It is intended to make a selection of these banner photographs to create a freely-downloadable A3 poster to mark World Albatross Day on 19 June 2020.

With thanks to Aude Schreiber and Tobie Getti.

John Cooper, ACAP Information Officer, 07 December 2019

BirdLife Australia is the national partner of BirdLife International.  Founded in 1901, the bird conservation charity is dedicated to delivering outstanding conservation outcomes for native birds and their habitats.  BirdLife Australia’s motto is ‘standing together to stop extinction’.  The organisation runs a number of multi-species landscape-scale bird conservation programmes.

BirdLife Australia has joined a growing number of BirdLife Partners in both hemispheres that have signaled their support for the inauguration next year of an annual World Albatross Day on 19 June, the date the Agreement for the Conservation of Albatrosses and Petrels (ACAP) was signed in Canberra in 2001.  Australia took the lead in initiating negotiations that led to the Agreement and is a founding Party, as well as being ACAP’s Depository (click here).  The ACAP Secretariat in based in Hobart in Tasmania.

Paul Sullivan, BirdLife Australia’s Chief Executive

Paul Sullivan, BirdLife Australia’s Chief Executive, has written to ACAP Latest News: “When albatrosses swallow the baited hooks used by longline fishing vessels, or interact with trawl gear, they drown.  Real international action is needed to stop this avoidable industrial-scale slaughter.”

Barry Baker, Convenor, Australasian Seabird Group

The Australasian Seabird Group (ASG), a special-interest group of BirdLife Australia, has also lent its support to World Albatross Day.  Its Convenor, Barry Baker, writes to ALN: “Many albatrosses and petrels are threatened with extinction and only slight increases in the mortality of adults can rapidly reduce populations within a couple of decades.  In a world where there is a focus on the sustainability of extractive industries it behoves fishers and fishery managers to take all necessary steps to reduce the impacts of their activities on non-target species, including seabirds.”

ACAP will liaise with BirdLife Australia (and the Australasian Seabird Group) over the next half a year in raising awareness of World Albatross Day and of the conservation crisis facing albatrosses and petrels among the concerned public in Australia, including the eight ACAP-listed species that breed within Australia and on its sub-Antarctic islands of Heard and Macquarie.

John Cooper, ACAP Information Officer, 06 December 2019

Sally Poncet (South Georgia Surveys) and colleagues have published in the journal Polar Biology on the results of a survey of breeding giant petrels Macronectes spp. on South Georgia (Islas Georgias del Sur)*.

The paper’s abstract follows:

“Information on the status of giant petrels breeding at South Georgia was previously based on studies at a small number of the archipelago's breeding sites.  Here, we report the results of the first complete archipelago-wide survey of breeding northern Macronectes halli and southern M. giganteus giant petrels in the austral summers 2005/2006 and 2006/2007.  We estimate that 15,398 pairs of northern and 8803 pairs of southern giant petrels bred at South Georgia.  These are the largest and second largest populations at any island group, representing 71.0% and 17.3%, respectively, of updated global estimates of 21,682 pairs of northern and 50,819 pairs of southern giant petrels.  A comparison of counts at locations surveyed in both 1986/1987–1987/1988 and 2005/2006–2006/2007 indicated increases of 74% and 27% in northern and southern giant petrels, respectively, over the intervening 18–20 years.  The greater increase in northern giant petrels was likely influenced by the recovery of the Antarctic fur seal Arctocephalus gazella population at South Georgia, which provides an abundant but transient food resource (carrion).  Due to allochrony, this provides greater benefits to northern giant petrels.  The large, and increasing, population of king penguins Aptenodytes patagonicus at South Georgia also provides a potentially valuable food resource.  The flexible and opportunistic foraging behaviour of giant petrels has contributed to their positive population trends.  Other, more specialised, seabirds such as albatrosses have declined at South Georgia in recent decades mainly because of problems at sea, compounded by greater predation pressure from the increasing populations of giant petrels.”

A giant petrel displays on South Georgia (Islas Georgias del Sur)*, photograph by Kirk Zufelt

With thanks to Richard Phillips and Anton Wolfaardt.

Reference:

Poncet, S., Wolfaardt, A.C., Barbraud, C., Reyes-Arriagada, R., Black, A., Powell, R.B. & Phillips, R.A. 2019.  The distribution, abundance, status and global importance of giant petrels (Macronectes giganteus and M. halli) breeding at South Georgia.  Polar Biology doi.org/10.1007/s00300-019-02608-y.

John Cooper, ACAP Information Officer, 05 December 2019

*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.