|Scientific Name:||Phoebastria irrorata (Salvin, 1883)|
Diomedea irrorata ssp. irrorata Salvin, 1883 — Collar et al. (1994)
Diomedea irrorata ssp. irrorata Salvin, 1883 — Sibley and Monroe (1990, 1993)
Diomedea irrorata ssp. irrorata Salvin, 1883 — Stotz et al. (1996)
Diomedea irrorata ssp. irrorata Salvin, 1883 — Collar and Andrew (1988)
|Taxonomic Source(s):||Robertson, C. J. R.; Nunn, G. B. 1998. Towards a new taxonomy for albatrosses. In: Robertson, G.; Gales, R. (ed.), Albatross biology and conservation, pp. 13-19. Surrey Beatty & Sons, Chipping Norton, Australia.|
|Identification information:||90 cm. Medium-sized albatross with white head, tinged buff-yellow on crown and nape. Chestnut-brown upperparts finely barred, coarser over rump. Brown upperwing, back and tail. Whitish breast, remainder of underparts barred, like upperparts. Whitish underwing, browner axillaries, brown around margins. Dull yellow bill. Bluish feet project beyond tail in flight. Juvenile like adult but with whiter head.|
|Red List Category & Criteria:||Critically Endangered B2ab(v) ver 3.1|
|Reviewer(s):||Butchart, S. & Symes, A.|
|Contributor(s):||Allport, G., Anderson, D., Croxall, J., Cruz, F., Huyvaert, K., Jiménez-Uzcátegui, G., McClellan, R. & Vargas, H.|
|Facilitator/Compiler(s):||Anderson, O., Ashpole, J, Bird, J., Butchart, S., Calvert, R., Moreno, R., Nel, D., Small, C., Stattersfield, A., Sullivan, B., Symes, A., Martin, R|
This species is classified as Critically Endangered because it has an extremely small breeding range, essentially confined to one island, and evidence suggests that it has experienced a substantial recent population linked to bycatch mortality in artisanal fisheries in its principal foraging grounds.
|Previously published Red List assessments:|
Phoebastria irrorata is endemic to Ecuador. It breeds primarily along the southern coast of Española Island in the Galápagos Islands, and, perhaps, a few pairs breed on La Plata Island off of Manabí province, Ecuador (Harris 1973). Breeding adults travel to the Peruvian upwelling region to feed (Anderson and Cruz 1998, H. Vargas and F. Cruz in litt. 2000, Awkerman et al. 2014), and in the non-breeding season birds move mainly east and south-east into the waters of the Ecuadorian and Peruvian continental shelf to the extreme north of Chile (Tickell 1996, Anderson and Cruz 1998, BirdLife International 2004, K. Huyvaert pers. comm. 2016). Rarely seen north of the equator, they are occasionally sighted off the coasts of Colombia (at least from El Choco) and Panama (Granizo 2002, Jahncke 2007).
On Española, the overall breeding population was considered to have been stable during the 20th Century. It was estimated at c.12,000 pairs in 1970-1971 (Harris 1973), 15,600-18,200 pairs in 1994 (Croxall and Gales 1998, Douglas 1998), and at least 34,694 adults in 2001 (Anderson et al. 2002). Although there has not been a global population estimate since 2001, surveys at two principal breeding sites on Española in 2007 demonstrated a decrease in the number of breeding birds since 2001, an overall population decrease (including non-breeders) at these sites since 1994 (Anderson et al. 2008). The breeding distribution has changed owing in part to vegetation regrowth following the eradication of goats (Anderson et al. 2002). Breeding no longer occurs at two inland sites, perhaps through redistribution to the coast (Anderson and Cruz 1998, Douglas 1998). On La Plata Island, there are probably fewer than 10-20 pairs (Anderson and Cruz 1998), and long-term data are too limited to assess population trends (Croxall and Gales 1998). In 2001, three adults were seen there with no evidence of breeding and a further 11 non-breeding adults were found on Isla Genovesa (Anderson et al. 2002).
Recent evidence has shown a 2-3% reduction in annual adult survival compared with that in the 1960s, which is thought to have driven recent dramatic declines in the breeding population (Awkerman et al. 2006, J. Croxall in litt. 2006, Anderson et al. 2008). Analysis of birds caught as intentional and incidental take in inshore fisheries has revealed that a disproportionate number of males are taken, which will result in further decreases to the effective population size given that this species has obligate bi-parental care (Awkerman et al. 2006). Even if immediate action was taken to curb adult mortality the population will continue to decline for a decade or so until the current cohort of juveniles reach breeding age (J. Croxall in litt. 2006). Breeding sites may be constrained by the extent and location of take-off points, which are in turn limited by dense vegetation (Gibbs and Woltz 2010).
Native:Chile; Colombia; Ecuador (Galápagos); Peru
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||On Española, the breeding population was estimated at c. 12,000 pairs in 1970-1971, 15,600-18,200 pairs in 1994 and at least 34,694 adults in 2001. On La Plata Island, there are probably fewer than 10-20 pairs.|
Trend Justification: Awkerman (2006) showed that adult survival declined between 1999 and 2004. These findings were supported by Anderson et al. (2008), and there is evidence that the population has declined between 1994 and 2007. Recent estimates at Punta Cevallos track declines in the numbers of breeding adults at a mean of 2.3% per annum since 1994, and 6.3% per annum since 2007 (Street 2013). Based on this information, the population is estimated to have declined by 1-19 % over the last 84 years.
|Current Population Trend:||Decreasing|
|Habitat and Ecology:||Behaviour This species breeds annually, arriving at colonies in late March (with males arriving earlier than females [Huyvaert et al. 2006], and older birds earlier than younger birds) (Harris 1973, Jahncke 2007), and laying from mid-April to late June. Chicks fledge between late December and early January. Some pairs skip breeding in certain years (Jahncke 2007, Street 2013). The age of first breeding is at four to six years of age or more, but individuals return to colonies, typically late in the season, from two years of age (Hirschfeld 2008, ACAP 2009, Street 2013). Habitat Breeding Nesting takes place on sparsely vegetated areas with lava surrounded by boulders (Harris 1973) but also, more recently, in thick scrub vegetation (Anderson et al. 2002). Diet It feeds on squid, fish, and crustaceans (Harris 1973), but scavenging food items disgorged by other species (such as cetaceans and boobies) may be an important feeding strategy (Merlen 1996, Anderson and Cruz 1998). A tracking study showed that during the breeding season, those birds that breed on Española made foraging trips eastwards towards the continental shelf and along the coast of Peru (Awkerman et al. 2014). The small number of birds from La Plata Island made much shorter but more frequent foraging trips to the continental shelf (Awkerman et al. 2014).|
|Continuing decline in area, extent and/or quality of habitat:||Unknown|
|Generation Length (years):||28.3|
|Movement patterns:||Full Migrant|
|Congregatory:||Congregatory (and dispersive)|
Recent studies indicate lower adult annual survival during 1995-2005 than in the 1960s as a result of direct mortality within some inshore fisheries, both through intentional harvesting for human consumption and incidental bycatch (Awkerman et al. 2006, Jiménez-Uzcátegui et al. 2006). This is supported by reports suggesting that the level of harvesting by fishers to supply food has increased dramatically in recent years (Alfaro-Shigueto et al. 2016). Around the Galápagos Islands, the transition from traditional to more modern fishing techniques such as longlining may pose a threat, as there is evidence of an increasing propensity for the species to follow fishing vessels (Awkerman et al. 2006). Longline fishing operations along the Peruvian and Ecuadorian coasts may therefore also threaten the species (Guillén et al. 2000, H. Vargas and F. Cruz in litt. 2000, Awkerman et al. 2006). Rates of bycatch incidence in the artisanal fishing communities off the coast of Ecuador have been estimated at 0.11 albatrosses/1,000 hooks (Alava and Haase 2011). Analysis of birds caught as intentional and incidental take in inshore fisheries has revealed that a disproportionate number of males are taken, and this appears to be at least partly responsible for a female-biased sex ratio (1.188 females per male) in adults (Awkerman et al. 2007).
The tiny population on La Plata Island is threatened by nest-predation by rats and cats, as well as the illegal collection of eggs and young (Carboneras 1992).
The species has shown susceptibility to El Niño Southern Oscillation (ENSO) events, perhaps owing to increased adult mortality or increased negative interactions with fisheries under these conditions (Rechten 1986, Awkerman et al. 2006).
Movement of eggs by parents (frequently resulting in loss of the egg) and mass desertions of eggs are yet to be fully explained (Anderson and Cruz 1998), however individuals are adversely affected by introduced mosquitoes during the breeding season (Anderson and Fortner 1988, Wiedenfeld and Jiménez-Uzcátegui 2008), and the increased abundance of these during warm El Niño events has been considered to cause mass egg abandonment in the past (Jahncke 2007).
Plastic ingestion appears to be a relatively minor threat in comparison with some other albatrosses (Anderson et al. 2008) but recent anecdotal reports suggest that breeding birds do ingest monofilament line and discarded net at-sea (K. Huyvaert unpubl. data).
Two hillside colonies apparently disappeared entirely by 1994 due to dense vegetation, and overall declines in populations in other inland areas have also been attributed to habitat loss associated with vegetation regrowth since goats were eradicated in 1978 (Jahncke 2007). Disease caused by parasites and pathogens is also a potential threat (Padilla et al. 2003, Wiedenfeld and Jiménez-Uzcátegui 2008, Jiménez-Uzcátegui et al. 2015). An oiled albatross was found on Española during 2001 (Anderson et al. 2003).
Conservation Actions Underway
Española is part of the Galápagos National Park and Marine Reserve. Industrial, but not artisanal, longlining is prohibited in the Galápagos Marine Reserve (Anderson et al. 2003). In 1979, the islands were declared a World Heritage Site. Española is well protected and has no alien fauna (goats having been eradicated in 1978 [Anderson and Cruz 1998, Jiménez-Uzcátegui et al. 2007]), and tourism is well-regulated (Carboneras 1992). A tortoise breeding programme has led to the release of over 2,000 tortoises on the island in the last 30 years; as the only native herbivore these animals may play a key role in vegetation control and maintaining suitable habitat for breeding albatrosses (Jahncke 2007). La Plata Island is part of Machalilla National Park, but is insufficiently protected (Carboneras 1992). The Agreement for the Conservation of Albatrosses and Petrels (ACAP) organised workshops in Peru and Ecuador in 2007 and 2008 to develop an Action Plan for Waved Albatross. There are proposals to protect more marine key biodiversity areas within the Galápagos Marine Reserve by amending the existing marine zoning scheme to reduce the impact from fishing (Edgar et al. 2008).
The Charles Darwin Foundation (CDF), Galapagos National Park Directorate (GNPD) and collaborators are carrying out long-term monitoring and on-going research using mark-recapture studies to determine changes in survival and reproduction, and investigating the relative importance of potential threats (heavy metals, diseases, climate change and human interaction).
Enumerate the breeding population regularly and establish a baseline to ascertain trends. Further evaluate extrinsic population threats (e.g., disease, plastic ingestion, contaminants). Further evaluate the threat of incidental and deliberate take in fisheries within the species's range. Adopt appropriate interim techniques to minimise bycatch. Assess the suitability of Isla de la Plata for breeding (Anderson et al. 2002). Improve protection for the Isla de la Plata colony.
|Amended reason:||Edited the Assessment rationale, Geographic Range, Habitat and Ecology, Threats and Conservation Actions text fields. New references have been incorporated, along with and also added Contributors and a new Facilitator.|
|Citation:||BirdLife International. 2017. Phoebastria irrorata (amended version of 2016 assessment). The IUCN Red List of Threatened Species 2017: e.T22698320A112205783.Downloaded on 19 January 2018.|
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