Sooty Albatrosses Research Articles

Cryptic variation in the sooty albatross Phoebetria fusca: genetic and morphological differences between Atlantic and Indian Ocean birds

Cryptic variation in the sooty albatross Phoebetria fusca: genetic and morphological differences between Atlantic and Indian Ocean birds

Habitat preferences of Phoebetria albatrosses in sympatry and allopatry

AbstractAimCompetition is often proposed to drive niche segregation along multiple axes in speciose communities. Understanding spatial partitioning of foraging areas is particularly important in species that are constrained to a central place. We present a natural experiment examining variation in habitat preferences of congeneric Southern Ocean predators in sympatry and allopatry. Our aim was to ascertain consistency of habitat preferences within species, and to test whether preferences changed in the presence of the congener.LocationSouthern Hemisphere.TaxonMultiple colonies of both species within the genus Phoebetria (sooty albatrosses).MethodsThe two Phoebetria albatrosses breed on islands located from ~37–55°S – sooty albatrosses (P. fusca) in the north and light‐mantled albatrosses (P. palpebrata) in the south – with sympatric overlap at locations ~46–49°S. We analysed GPS and PTT tracks from 87 individuals and multiple remotely sensed environmental variables using GAMs, to determine and compare the key factors influencing habitat preference for each species at each breeding colony.ResultsWhile foraging habitat preferences are consistent in light‐mantled albatrosses, there is divergence of preferences in sooty albatrosses depending on whether they are in sympatry with their congener or in allopatry.Main ConclusionsThis study represents the most comprehensive work on this genus to date and highlights how habitat preferences and behavioural plasticity may influence species distributions under different competitive conditions.

Fine-scale behaviour and population estimates of endangered sooty albatross suggest low exposure (while not excluding high sensitivity) to bycatch

Fine-scale behaviour and population estimates of endangered sooty albatross suggest low exposure (while not excluding high sensitivity) to bycatch

Gauging the threat: exposure and attraction of sooty albatrosses and white-chinned petrels to fisheries activities in the Southern Indian Ocean

Abstract Bycatch risk assessments typically rely on spatial overlaps between seabirds and fishing vessels but should also consider seabirds’ position in the attraction spectrum. Investigating seabird-fishery interactions in relation to habitat use is vital for species-specific risk assessments. To address this, we studied interactions between sooty albatrosses (SA) and white-chinned petrels (WCP) with fisheries. GPS data from 20 SA and 18 WCP individuals from Marion Island were analysed alongside Automatic Identification System-derived boat locations over two breeding seasons. We calculated encounter and attraction rates and correlated them with marine habitat characteristics. SA interactions occurred in deeper, warmer waters compared to their foraging habitat when vessels were absent, with 20% of individuals encountering and only 5% being attracted to boats. In contrast, WCP interactions occurred in shallow, warm South African shelf waters, consistent with their typical foraging habitats, with 72% encountering and 56% attracted to boats. These results highlight the need for continued reinforcement of mitigation measures for WCP. Despite the low attraction rates for SA, ongoing vigilance is required due to their smaller population size, which heightens the potential impact of illegal fisheries. The comparison of species along an attraction spectrum contributes to refining risk assessments and informs species-specific conservation strategies.

Cephalopod prey of light-mantled sooty albatross Phoebetria palpebrata, resource partitioning amongst Kerguelen albatrosses, and teuthofauna of the southern Indian Ocean

The cephalopod diet of the light-mantled sooty albatross Phoebetria palpebrata was determined for the first time at the subantarctic Kerguelen Islands by sorting ∼7000 accumulated beaks from 66 regurgitated boluses. Twenty-two taxa were identified, including four dominant squid species that are all endemic to the Southern Ocean: Galiteuthis glacialis (49.8% of the lower beaks) Psychroteuthis glacialis (18.5%), Martialia hyadesi (16.2%) and Moroteuthopsis longimana (6.9%). Beak δ13C values indicated that all adult P. glacialis, almost all juvenile M. longimana, and most adult G. glacialis were caught in Antarctic waters, while albatrosses preyed upon juvenile M. hyadesi in subantarctic waters. Comparative analysis of lower beaks accumulated in food samples of Kerguelen albatrosses showed that the four main sympatric albatross species segregate primarily by species-specific foraging grounds. Light-mantled sooty albatross feed on the Antarctic P. glacialis, wandering albatross Diomedea exulans on subantarctic and subtropical histioteuthids (41.4%), and grey-headed albatross Thalassarche chrysostoma and black-browed albatross T. melanophris on subantarctic ommastrephids (69.3% and 65.7%, respectively), with black-browed albatross also preying upon neritic endemic octopuses (17.6%). Cephalopod prey of Kerguelen albatrosses highlight the abundance and importance of some squids in the functioning of the pelagic ecosystem of the southern Indian Ocean, such as ommastrephids, M. longimana, P. glacialis, Histioteuthis atlantica, H. eltaninae, and G. glacialis. Based on the diet of the light-mantled sooty albatross, P. glacialis appears common in high-Antarctic waters of the southern Indian Ocean, whereas the poorly known Psychroteuthis sp. B (Imber) is evidently present in Antarctic waters south of the Kerguelen Islands.

Editorial

Editorial

Multi-decadal changes in the at-sea distribution and abundance of black-browed and light-mantled sooty albatrosses in the southwest Pacific Ocean

Abstract Many long-term studies have reported changes in seabird abundance and distribution in response to climate change and various anthropogenic activities. However, a greater understanding of how species are responding to change over large spatial and temporal scales are required—particularly at high latitudes such as the Southern Ocean. We examined black-browed Thalassarche melanophris (BBAL) and light-mantled sooty Phoebetria palpebrata albatross (LMSA) observations spanning over 50 years. Both species have a wide-ranging distribution in a rapidly changing Southern Ocean. We used generalized additive models (GAMs) to investigate environmental drivers of their abundance and occurrence. Our results show that climate indices, sea surface temperature and sea surface height are the main drivers influencing the distribution and abundance of both species. The abundance of BBAL southeast of Australia was observed to be decreased substantially whereas no significant change was observed in the abundance of LMSA. Both species demonstrated contrasting distributions along their latitudinal gradient with BBAL showing early stages of a southward range shift. Our analyses suggest that responses to climate change are species-specific. These rare, long-term data have provided an understanding of species’ responses to past changes in the marine environment and can provide critical information for future conservation and management.

Phoebetria fusca

This datasheet on Phoebetria fusca covers Identity, Distribution.

Non-breeding distribution, activity patterns and moulting areas of Sooty Albatrosses (Phoebetria fusca) inferred from geolocators, satellite trackers and biochemical markers

Non-breeding distribution, activity patterns and moulting areas of Sooty Albatrosses (Phoebetria fusca) inferred from geolocators, satellite trackers and biochemical markers

Foraging in a dynamic environment: Response of four sympatric sub-Antarctic albatross species to interannual environmental variability.

Seasonal and annual climate variations are linked to fluctuations in the abundance and distribution of resources, posing a significant challenge to animals that need to adjust their foraging behavior accordingly. Particularly during adverse conditions, and while energetically constrained when breeding, animals ideally need to be flexible in their foraging behavior. Such behavioral plasticity may separate “winners” from “losers” in light of rapid environmental changes due to climate change. Here, the foraging behavior of four sub‐Antarctic albatross species was investigated from 2015/16 to 2017/18, a period characterized by pronounced environmental variability. Over three breeding seasons on Marion Island, Prince Edward Archipelago, incubating wandering (WA, Diomedea exulans; n = 45), grey‐headed (GHA, Thalassarche chrysostoma; n = 26), sooty (SA, Phoebetria fusca; n = 23), and light‐mantled (LMSA, P. palpebrata; n = 22) albatrosses were tracked with GPS loggers. The response of birds to environmental variability was investigated by quantifying interannual changes in their foraging behavior along two axes: spatial distribution, using kernel density analysis, and foraging habitat preference, using generalized additive mixed models and Bayesian mixed models. All four species were shown to respond behaviorally to environmental variability, but with substantial differences in their foraging strategies. WA was most general in its habitat use defined by sea surface height, eddy kinetic energy, wind speed, ocean floor slope, and sea‐level anomaly, with individuals foraging in a range of habitats. In contrast, the three smaller albatrosses exploited two main foraging habitats, with habitat use varying between years. Generalist habitat use by WA and interannually variable use of habitats by GHA, SA, and LMSA would likely offer these species some resilience to predicted changes in climate such as warming seas and strengthening of westerly winds. However, future investigations need to consider other life‐history stages coupled with demographic studies, to better understand the link between behavioral plasticity and population responses.

Important areas and conservation sites for a community of globally threatened marine predators of the Southern Indian Ocean

In the Southern Ocean, the impact of environmental changes and increasing human encroachment is causing declines in several populations of seabirds. Amsterdam island (77°33′E; 37°50′S) hosts some emblematic but globally threatened seabird species with alarming population trends. In 2017, concerns about Amsterdam Island's marine biodiversity led to the extension of a marine reserve to the boundaries of the exclusive economic zone (EEZ). Nevertheless, it is unknown whether this protected area is sufficiently large to encompass the most important foraging hotspots of the threatened seabirds, particularly during key stages of their life cycle (e.g. breeding period). We analysed movements of four threatened seabird species using a tracking dataset acquired over several breeding seasons from Amsterdam Island: Amsterdam albatross Diomedea amsterdamensis, sooty albatross Phoebetria fusca, Indian yellow-nosed albatross Thalassarche carteri and northern rockhopper penguin Eudyptes moseleyi. Our objectives were threefold: (1) characterise the at-sea distribution of the above-mentioned populations and delineate the marine Important Bird and Biodiversity Areas (mIBAs) triggered by them; (2) assess the potential threat at-sea by quantifying the overlap between seabird distribution and longline fishing efforts; (3) evaluate the coverage of identified mIBAs by marine protected areas and suggest complementary conservation actions. The identified important areas fell within the boundaries of the EEZ, but vastly exceeded the former reserve. Thus, our results reinforce the justification of the recent expansion of the reserve to the boundaries of the EEZ. However, overall seabird distributions extended beyond the EEZ (5 to 50% of the locations) and we found substantial overlap with longline fishing in the high seas. Our results provide a spatio-temporal envelope of where and when bycatch mitigation and observer coverage of longline fisheries should be mandated and enforced.

The avian collection of the former Saint Augustine College of the Regional Natural History Museum in Plovdiv

The paper presents a catalogue of bird specimens (dry mounted preserves) survived after the closing (1948) of the former Catholic College “Saint Augustine”. Currently, the studied specimens are kept at the Regional Natural History Museum in Plovdiv. The collection includes a total of 193 species of birds of 81 families and 28 orders, represented by 205 specimens (circa two percent of the recent World avifauna). Over 15 percent of the species have an IUCN conservation status (NT to CR). The most valuable are the following specimens: critically endangered grey-backed myna (Acridotheres tricolor) and two endangered species - echo parakeet (Psittacula eques) and sooty albatross (Phoebetria fusca). This is the 2nd largest collection of exotic birds in Bulgaria.

Avian cholera outbreaks threaten seabird species on Amsterdam Island.

Infectious diseases may be particularly critical for the conservation of endangered species. A striking example is the recurrent outbreaks that have been occurring in seabirds on Amsterdam Island for the past 30 years, threatening populations of three Endangered seabird species and of the endemic, Critically Endangered Amsterdam albatross Diomedea amsterdamensis. The bacteria Pasteurella multocida (avian cholera causative agent), and to a lesser extent Erysipelothrix rhusiopathiae (erysipelas causative agent), were both suspected to be responsible for these epidemics. Despite this critical situation, demographic trends were not available for these threatened populations, and the occurrence and characterization of potential causative agents of epizootics remain poorly known. The aims of the current study were to (i) provide an update of population trends for four threatened seabird species monitored on Amsterdam Island, (ii) assess the occurrence of P. multocida, and E. rhusiopathiae in live birds from five species, (iii) search for other infectious agents in these samples and, (iv) isolate and genotype the causative agent(s) of epizooties from dead birds. Our study shows that the demographic situation has worsened substantially in three seabird species during the past decade, with extremely low reproductive success and declining populations for Indian yellow-nosed albatrosses Thalassarche carteri, sooty albatrosses Phoebetria fusca, and northern rockhopper penguins Eudyptes moseleyi. Pasteurella multocida or E. rhusiopathiae were detected by PCR in live birds of all five investigated species, while results were negative for eight additional infectious agents. A single strain of P. multocida was repeatedly cultured from dead birds, while no E. rhusiopathiae could be isolated. These results highlight the significance of P. multocida in this particular eco-epidemiological system as the main agent responsible for epizootics. The study stresses the urgent need to implement mitigation measures to alter the course of avian cholera outbreaks threatening the persistence of seabird populations on Amsterdam Island.

Status and trends of albatrosses in the French Southern Territories, Western Indian Ocean

Today albatrosses are threatened worldwide, especially by fishing activities, and many populations are currently in decline. Albatrosses breeding at the French Southern Territories in the south-western Indian Ocean, on the Crozet, Kerguelen and Saint-Paul–Amsterdam island archipelagos, are monitored regularly. This monitoring has been based on a sample of species and sites, and there was a need for an assessment of the population trends for all species at each site. During the past 3 years most populations have been surveyed, allowing an assessment of the trends of albatrosses breeding at the archipelagos of the French Southern Territories over the past 40 years. Wandering Albatrosses show similar trends at all sites within the Crozet and Kerguelen archipelagos, with a recent recovery of colonies after strong declines in the 1970s. Amsterdam Albatrosses are increasing, albeit at lower rates during recent years. Indian Yellow-nosed Albatrosses show a global decline over the entire range. The trends among Black-browed and Grey-headed Albatrosses vary between colonies and archipelagos. Sooty Albatrosses have continuously decreased in numbers whereas Light-mantled Albatross numbers vary considerably between years, with an overall increase over the past 30 years. These results confirm that the French Southern Territories in the south-west Indian Ocean support a significant portion of the world populations of several albatross species. Several species appear to be steadily decreasing probably because of the impact of fisheries and disease outbreaks. The reasons for different trends among populations of the same species are not well understood and require further investigation.

Ontogeny, tissue, and species but not sex influence stable isotopic values of three albatross species

The use of indirect dietary markers, including stable isotopes, has immensely improved our knowledge of seabird trophic ecology throughout their annual cycle. Important aspects include differences in trophic niche between adults and chicks at the intra- and inter-specific levels and tissue-dependent differentiation in chicks. Using stable isotopic niche as a proxy for trophic ecology, we investigated how three closely related albatross species co-exist in the sub-Antarctic Prince Edward Islands. The effects of age, sex, tissue, and species on the isotopic niche were observed for Grey-headed Thalassarche chrysostoma, Sooty Phoebetria fusca, and Light-mantled Phoebetria palpebrata Albatrosses breeding on Marion Island. At the end of chick-rearing, carbon and nitrogen stable isotope values differed according to age, tissue, and species but not the sex of either adults or chicks. A complex pattern was revealed as the three species exhibited contrasting results. For example, values for δ13C or δ15N of chick blood could be depleted, enriched or similar relative to that of adults, depending on species. Stable isotope differences between blood and feathers likely reflect differences in their amino acid composition, while adult/chick differences will relate to their different physiological needs and diet. The results indicate that co-existence of the three species on the island is facilitated through resource partitioning among species in terms of foraging areas and in the trophic levels at which adults feed for themselves and their chicks. This work brings new insights into the effect of intrinsic factors on the foraging ecology of marine top predators.

The distribution of breeding Sooty Albatrosses from the three most important breeding sites: Gough, Tristan and the Prince Edward Islands

ABSTRACTSooty Albatrosses (Phoebetria fusca; Endangered) breed only on sub-Antarctic islands in the South Atlantic and south-west Indian Oceans, with most of the population at Gough Island (≈37%), the Prince Edward Islands (≈24%) and the Tristan da Cunha archipelago (≈20%). Breeding Sooty Albatrosses from all three of these populations were tracked during the incubation and brood-guard periods. Birds from Marion Island (Prince Edwards) ranged farther north, despite being the most southerly of the three study sites. Tristan-Gough Sooty Albatrosses concentrated mostly around the Sub-Antarctic Front (SAF) in the southern Atlantic Ocean, whereas Marion birds were associated with both the SAF and the Sub-Tropical Front (STF) in the southern Indian Ocean. Our tracking data describe where 80% of breeding Sooty Albatrosses forage during the incubation and brood-guard period, including the first records of birds from Marion and Tristan. Such data are important to identify key areas where these threatened birds need protection from mortality on long-line fishing gear. Overlap with the distribution of tuna long-line effort was greater for Sooty Albatrosses from Tristan da Cunha and Gough Island than for Marion birds, suggesting that birds breeding at Atlantic colonies might be at greater risk of bycatch mortality in this fishery.

Feather mercury concentrations in Southern Ocean seabirds: Variation by species, site and time

We studied mercury contamination in 25 seabird species breeding along a latitudinal gradient across the Southern Ocean, from Gough Island (40°S) through Marion Island (47°S) to Byers Peninsula (63°S). Total mercury concentrations in body feather samples of adults caught at breeding colonies from 2008 to 2011 were determined. Krill (Euphausia spp.) and other zooplankton consumers had low mercury concentrations (gentoo penguin Pygoscelis papua, chinstrap penguin Pseudomonas Antarctica, common diving petrel Pelecanoides urinatrix, broad-billed prion Pachyptila vittata; mean levels 308–753 ng g−1), whereas seabirds consuming squid or carrion had high mercury concentrations (ascending order: Kerguelen petrel Aphrodroma brevirostris, southern giant petrel Macronectes giganteus, soft-plumaged petrel Pterodroma mollis, sooty albatross Phoebetria fusca, Atlantic petrel Pterodroma incerta, northern giant petrel Macronectes halli, great-winged petrel Pterodroma macroptera; 10,720–28038 ng g−1). The two species with the highest mercury concentrations, northern giant petrels and great-winged petrels, bred at Marion Island. Among species investigated at multiple sites, southern giant petrels had higher mercury levels at Marion than at Gough Island and Byers Peninsula. Mercury levels among Byers Peninsula seabirds were low, in two species even lower than levels measured 10 years before at Bird Island, South Georgia. Replicate measurements after about 25 years at Gough Island showed much higher mercury levels in feathers of sooty albatrosses (by 187%), soft-plumaged petrels (53%) and Atlantic petrels (49%). Concentrations similar to the past were detected in southern giant petrels at Gough and Marion islands, and in northern giant petrels at Marion. There were no clear indications that timing of moult or migratory behavior affected mercury contamination patterns among species. Causes of inter-site or temporal differences in mercury contamination could not be verified due to a lack of long-term data related to species’ diet and trophic levels, which should be collected in future together with data on mercury contamination.

Recent population trends of sooty and light-mantled albatrosses breeding on Marion Island

Sub-Antarctic Marion Island is one of the few islands where both species of Phoebetria albatrosses breed sympatrically. The last published assessment of their population trends, which reported counts up to 2008, concluded that the numbers of breeding pairs of sooty albatross P. fusca (Endangered) were decreasing, whereas numbers of light-mantled albatross P. palpebrata (Near Threatened) were increasing. Extending the counts to 2014 reversed these trends, with numbers of sooty albatrosses increasing from 2006 to 2014, and numbers of light-mantled albatrosses decreasing from 2007 to 2014. Confidence in island-wide counts is low due to the cryptic nature of the albatrosses on their largely inaccessible cliff-side nest sites, as well as counts for sooty albatrosses taking place late in the incubation period when 10−20% of nests have already failed. Given the greater conservation concern for the sooty albatross, we recommend that dedicated annual counts be conducted during the early incubation period, and be repeated shortly after the chicks hatch (late December), mid-way through the nestling period (late February) and prior to fledging (late April), to give a better idea of breeding success. Count zones also should be revised to facilitate more accurate counts, ensuring more reliable estimates of sooty albatross population trends at Marion Island.

‘Scalping’ of albatross fledglings by introduced mice spreads rapidly at Marion Island

AbstractHouse mice (Mus musculusL.) were introduced to sub-Antarctic Marion Island more than two centuries ago, and have been the only introduced mammal on the island since 1991 when feral cats were eradicated. The first mouse-injured wandering albatross (Diomedea exulansL.) chick was found in 2003 and since then attacks have continued at a low level affecting <1% of the population. In 2009, the first ‘scalpings’ were detected; sooty albatross (Phoebetria fuscaHilsenberg) fledglings were found with raw wounds on the nape. In 2015, mice attacked large chicks of all three albatross species that fledge in autumn: grey-headed (Thalassarche chrysostomaForster) (at least 102 wounded chicks; 4.6% of fledglings), sooty (n=45, 4.3%) and light-mantled albatross (P. palpebrataForster) (n=1, 4%). Filming at night confirmed that mice were responsible for wounds. Attacks started independently in small pockets all around the island’s 70 km coastline, separated by distances hundreds of times greater than mouse home ranges. The widespread nature of mouse attacks in 2015 on large, well-feathered chicks is alarming and highlights not only Marion Island as a priority island for mouse eradication but also that mice alone may significantly affect threatened seabird species.

Failure to launch: evidence of protracted parental care in albatrosses

Most albatrosses have well defined breeding seasons (Tickell 2000). Fledging tends to be spread over a longer period than laying or hatching because the duration of the chick-rearing stage is more variable than that of incubation (Warham 1990). However there are few records of albatross chicks extending fledging periods by more than a month or two (but see Brown & Adams 1984). We were thus surprised to see a juvenile Sooty Albatross Phoebetria fusca on a nest near the meteorological station on Gough Island (40°20'S 9°55'W) during the 2014-15 breeding season, three months after Sooty Albatross chicks usually fledge from Gough Island (Ryan 2007; most chicks fledge in May-June, and in 2015 the last chick near the weather station departed between 17 and 25 July). The late-fledging juvenile was first observed on 17 September 2014 and remained on its nest until at least 14 October, but apparently fledged by 19 October (the nest was empty, and no carcass was found). It seemed to be in good health throughout this period, and on being approached, it clapped its bill in the manner typical of a large nestling. Characters that indicated it was a juvenile bird still in its first year were the virtual lack of a white eye-ring, no yellow sulcus stripe on the bill, and uniformly aged, fresh plumage still with pale fringes to the back coverts (Figure 1; Marchant & Higgins 1990). Assuming a mean hatching date in mid December (Ryan 2007), this gives a fledging period of around 300 days, much longer than the 164 ± 9 SD days recorded at Ile de la Possession, Crozet Islands (46°25'S 51°45'E: maximum 178 days; Tickell 2000).