Justification of Red List Category
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (extent of occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population size is extremely large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). The population trend appears to be increasing, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). For these reasons the species is evaluated as Least Concern.
The Falklands Islands (Islas Malvinas) holds the largest number of breeding individuals, estimated at 475,500-535,000 pairs in 2010; Wolfaardt 2012). Most other breeding sites holding large numbers of breeding individuals are in Chile with 55,000 pairs estimated on Diego Ramirez in 2003, 58,000 pairs on Ildefonso in 2012 (Robertson et al. 2013), and 15,500 pairs on Diego de Almagro in 2002 (Lawton et al. 2003). The population size on South Georgia (Georgias del Sur) is difficult to estimate, but based on Poncet et al. (2006) and assuming the rate of decline was c.4% (similar to that of Bird Island), the population there may have been down to 56,000 pairs by 2012 (ACAP unpubl. data). However, this may be an underestimate as, based on surveys conducted in 2014/15 covering 30% of the South Georgia (Georgias del Sur) population, declines actually could have been at c.1.8% per year between 2005 and 2014 (Poncet et al. 2006, A. Wolfaardt in litt. 2016). There are an estimated c.5,800 pairs in other populations (Antipodes, Campbell, Heard and MacDonald, Crozet, Kerguelen, Macquarie, Snares; ACAP unpubl. data), giving a potential global population of c.700,000 pairs, which equates to 1,400,000 mature individuals.
Surveys of the Falkland Islands (Islas Malvinas) population have suggested this population is on the increase, with a 2010 archipelago-wide survey revealing (through aerial and ground-based surveying) an annual increase of at least 4% between 2005 and 2010. This is supported by further aerial surveys from later in the 2010 breeding season and demographic data (Wolfaardt 2012). From this it has also been concluded that the population of Black-browed Albatross on these islands has likely increased since the first archipelago-wide survey in 2000, and potentially since the first ground-based surveys on Beauchêne and Steeple Jason islands in the 1980s. Chilean populations are also likely increasing, as work suggests that the Diego Ramirez and Ildefonso archipelagos (supporting c.85% of the Chilean population) increased by 52% and 18% respectively between 2002 and 2011 (or 23% for both sites combined) (Robertson et al. 2013). Further surveys in 2014 indicated that the Diego Ramirez population increased by a further 29% between 2011 and 2014, while the numbers at Ildefonso remained stable (A. Wolfaardt in litt. 2016). The trend for South Georgia (Georgias del Sur) appears to be a decline, previously estimated as 4% per year, but now better estimated, based on surveys conducted in 2014/15 covering 30% of the South Georgia (Georgias del Sur) population, at c.1.9% per year between 2003/4 and 2014/5 (Poncet et al. 2006, A. Wolfaardt in litt. 2016, Poncet et al. 2017).
With the Falklands Islands (Islas Malvinas) and Chilean populations making up the vast majority of the global population it is highly likely that this is currently increasing, and potentially has been since the 1980s. The generation length for this species is long (21.5 years), and data is not available to fully assess population trends over 3 generations into the past. However, given the newer information regarding trends in Chile and South Georgia (Georgias del Sur) it now seems unlikely that the species is in the process of undergoing a decline over 3 generations (commencing in 1980 and continuing into the future).
Thalassarche melanophris has a circumpolar distribution ranging from subtropical to polar waters (ACAP 2009), breeding in the Falkland Islands (Islas Malvinas), Islas Diego Ramirez, Ildefonso, Diego de Almagro, Isla Evangelistas and islets in Tierra del Fuego and in the Mallaganes region (Chile), South Georgia (Georgias del Sur), Crozet and Kerguelen Islands (French Southern Territories), Heard, McDonald and Macquarie Islands (Australia), and Campbell and Antipodes Islands, New Zealand (Croxall and Gales 1998, ACAP 2009). One colony was also recorded on Snares Island in 1986 (ACAP 2009). The total breeding population is estimated at c.700,000 pairs, c.72% at the Falkland Islands (Islas Malvinas), 19% in Chile and 8% at South Georgia (ACAP unpubl. data). The population size is considered to be increasing.
Behaviour This is a colonial, annually breeding species, although only 75% of successful breeders and 67% of failed breeders breed the following year. Individuals arrive at colonies in September, laying in early October with chicks hatching in December and fledging between April and May. Immature birds begin to return to land at the age of two with the numbers of returning birds increasing up to the age of six. The median age of first breeding is 10 years (range 8-13) (ACAP 2009). During incubation, breeding birds tend to remain in areas adjacent to or to the north of their colonies in the shelf, shelf-break and shelf-slope waters (ACAP 2009). At Campbell Island, Black-browed Albatross show a unique bimodal foraging strategy, alternating between short trips to shelf areas around the breeding site and long trips to the Polar Front (Waugh et al. 1999). Birds foraging over the Benguela Current during the winter also showed a bimodal feeding strategy, alternating trips over deep, oceanic waters with trips over the continental shelf (Petersen et al. 2008). During incubation on South Georgia, satellite tracking reveals males and females forage in different areas with almost no overlap (Phillips et al. 2004). After breeding, birds from the Falkland Islands (Islas Malvinas) winter on the Patagonian Shelf (N. Huin in litt 2008) and estuaries in Buenos Aires province (Río de la Plata and El Rincón) (Copello et al. 2013), whereas birds from South Georgia predominantly migrate to South African waters, spending the first half of the winter in the highly productive Benguela Current (Phillips et al. 2005). Black-browed Albatross from Chile make use of the Chilean Shelf, the Patagonian Shelf, and some spend the non-breeding season around north New Zealand.
Habitat Breeding The species nests colonially on steep slopes with tussock grass, sometimes on cliff terraces, but the largest colonies in the Falklands (Islas Malvinas) are on flat ground along the shore line.
Diet It feeds mainly on crustaceans, fish and squid, and also on carrion and fishery discards (Cherel et al. 2002, Arata et al. 2003, Xavier et al. 2003, Mariano Jelicich et al. 2014). A Wilson’s Storm-petrel was recorded in the stomach contents of a bycaught individual on the Patagonian Shelf (Seco Pon and Gandini 2008), and while various Sphenisciformes and Procellariiformes have been found in the stomachs of albatrosses, penguins tend to be recorded more frequently, although none are typical prey items (Seco Pon and Gandini 2008). The exact composition of its diet varies depending on locality and year (ACAP 2009).
Foraging Range During chick-rearing, breeding T. melanophrys initially stay in shelf to shelf-slope areas very close to their colonies (within c. 500 km). Later, birds from Chile and South Georgia (Islas Georgias del Sur) may also travel up to c. 3,000 km from their breeding sites, especially to the Antarctic Peninsula and South Orkney Islands, but birds from the Falkland Islands (Islas Malvinas) and Kerguelen continue to remain close to their colonies (ACAP 2009). During the non-breeding period adult birds from the Falkland Islands (Islas Malvinas) dispersed north of their colonies up to southern Brazil (Copello et al. 2013).
The species is threatened by current longline fisheries and the development of new fisheries over much of the Patagonian Shelf, around South Georgia, off the southern African coast and in the Southern Ocean (Tuck and Polacheck 1997, Prince et al. 1998, Schiavini et al. 1998, Stagi et al. 1998). It is one of the most frequently killed species in many longline fisheries including tuna longliners off southern Africa, the pelagic longline swordfish fishery off Chile and Argentine longliners targeting toothfish and kingclip on the Patagonian Shelf (Murray et al. 1993, Gales et al. 1998, Ryan and Boix-Hinzen 1998, Schiavini et al. 1998, Stagi et al. 1998, Ryan et al. 2002 Reid and Sullivan 2004, Bugoni et al. 2008, Favero et al. 2013). Capture rates can vary greatly according to season, number of hooks and type of longline (Bugoni et al. 2008). Mortality in trawl fisheries has also been identified as a major source of mortality for this species over the Patagonian Shelf (Sullivan and Reid 2002, Favero et al. 2011, Seco Pon et al. 2015) and South Africa (Watkins et al. 2007), and was previously estimated to result in minimum 5,000 individuals killed per annum across the deep-water hake trawl fishery in South African waters during winter (Watkins et al. 2008). This threat has since been significantly reduced, largely due to the introduction and use of mitigation measures (Maree et al. 2014). In addition to the commercial longline fishery, this species was the second most frequently recorded bycatch in artisanal fisheries off the coast of Peru (Mangel 2012), suggesting that these poorly regulated fisheries represent a considerable threat to the proportion of the population that forages in the Humboldt current.
Climate change also poses a significant threat to the species. Barbraud et al. (2011) showed that climatic fluctuations have a negative impact on survival. Positive sea-surface temperature anomalies at the species’ wintering ground around Tasmania were identified to have a negative impact on breeding success, while positive sea-surface temperature anomalies had a positive effect (Nevoux et al. 2007, Rolland et al. 2008). Extremely low or nil breeding success in some years at South Georgia (Islas Georgias del Sur) has also been linked to periods of low prey availability in the krill-based trophic system of that region of the Southern Ocean (Xavier et al. 2003), which could be a result of either or both climatic events or overfishing.Invasive American Mink Mustela vison may pose a serious threat to the species, and feral cats Felis catus are thought to impact on colonies at Jeanne d'Arc Peninsula (ACAP 2009). Volcanic eruptions may pose a risk to certain colonies, but the vulnerable proportion of the population and the probability of incidence is considered too low to cause significant future decline.
Conservation Actions Underway
CMS Appendix II and ACAP Annex 1. It is monitored at South Georgia, Kerguelen, Campbell, Diego Ramirez and the Falkland Islands (Islas Malvinas). Most breeding sites are reserves. Heard and McDonald, Macquarie, and the New Zealand islands are World Heritage Sites. An initial census of Chilean islands has been completed (Lawton et al. 2004). Mitigation measures have significantly reduced the mortality caused by trawl fishing in South Africa (Maree et al. 2014). An eradication programme targeting rodents commenced in 2010 and has been successfully completed (A. Wolfaardt in litt. 2016).
88 cm. Medium-sized albatross. Dark grey saddle and upperwings contrast strongly with white head, rump and underparts. Underwing is largely white with very broad, rather irregular, black margins. Dark eyebrow and yellow-orange bill with darker red-orange tip. Juveniles and sub-adults have dark, horn-coloured bills with dark tips, grey on head and collar, and dark underwing, which lightens with age. Similar spp. Juveniles can be very similar to juvenile Grey-headed Albatross Thalassarche chrysostoma but show faintly black-tipped bills and darker ridges.
Text account compilers
Sullivan, B., Symes, A., Wheatley, H., Calvert, R., Fjagesund, T., Hermes, C., Anderson, O., Butchart, S., Martin, R., Small, C., Stuart, A.
Copello, S., Stanworth, A., Arata, J., Seco Pon, J., Croxall, J., Robertson, G., Misiak, W., Wolfaardt, A., Huin, N., Phillips, R.
BirdLife International (2020) Species factsheet: Thalassarche melanophris. Downloaded from http://www.birdlife.org on 11/07/2020. Recommended citation for factsheets for more than one species: BirdLife International (2020) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 11/07/2020.