Foraging ecology and interactions with fisheries of wandering albatrosses (Diomedea exulans) breeding at South Georgia

J. C. Xavier, P. N. Trathan, J. P. Croxall, A. G. Wood, Guillermo P Podesta, P. G. Rodhouse

Research output: Contribution to journalArticle

78 Citations (Scopus)

Abstract

Knowledge about the areas used by the foraging wandering albatross, Diomedea exulans, its prey and overlap with longline fisheries is important information not only for the conservation of this species but also for furthering our understanding of the ecology of its prey. We attached satellite-tracking devices and activity recorders to wandering albatrosses between May and July of 1999 and 2000 (years of differing food availability around South Georgia) in order to assess inter-annual variation in the main foraging areas, association with oceanographic features (i.e. fronts, bathymetry), diet and interactions with fisheries. The overall foraging patterns of the tracked birds were similar in 1999 and 2000, ranging between southern Brazil (28°S) and the Antarctic Peninsula (63°S) and between the waters off Tristan da Cunha (19°W) and the Patagonian Shelf and oceanic waters south of Cape Horn (68°W) in the South Atlantic. In 1999, wandering albatrosses spent most time in sub-Antarctic oceanic waters, their trip durations were significantly longer and they fed on fish and cephalopods (53 and 42% by mass, respectively). In contrast, in 2000, they spent more time in Antarctic waters, foraging trips were shorter and the diet was predominantly fish (84% by mass). Wandering albatrosses were associated with the sub-Antarctic Front (SAF; both years), Subtropical Front (STF; in 1999) and the Tropical Front (TF; in 2000) suggesting that this species exploits prey concentrated at oceanic fronts. Fisheries discards also seemed to provide a very good source of food. Several fish species that are targeted (e.g. Patagonian toothfish, Dissostichus eleginoides) or are available as offal/discards from commercial fisheries (e.g. the macrourids, Antimora rostrata and Macrourus holotrachys) were mainly associated with the South Georgia shelf and the Patagonian Shelf, respectively. Wandering albatross foraging areas overlapped with longline fisheries in three different regions: around South Georgia, at the Patagonian Shelf and in oceanic waters north of 40°S. Females commuted more frequently to the Patagonian Shelf and to oceanic areas where longline fisheries were operating. Males, on the other hand, spent more time on the shelf/shelf slope of South Georgia where they were more at risk from the local Patagonian toothfish fishery, particularly in 2000. These results emphasize that inter-annual variation in foraging preferences could lead to increased incidental mortality of this vulnerable species. Potential evidence for this is provided by a satellite-tracked wandering albatross (male; 1.8-day trip), whose diet contained a Patagonian toothfish head and a longline hook, and who spent extensive time in the water (44% of the time wet; 0.3 days of the trip) where a Patagonian toothfish longline fishing vessel was operating.

Original languageEnglish (US)
Pages (from-to)324-344
Number of pages21
JournalFisheries Oceanography
Volume13
Issue number5
DOIs
StatePublished - Sep 2004

Fingerprint

fishery
breeding
fisheries
foraging
ecology
diet
water
annual variation
fishery discard
fish
oceanic front
oceanographic feature
Tristan da Cunha
fishing vessel
cephalopod
food availability
fishing boats
bathymetry
Cephalopoda
bird

Keywords

  • Diet
  • Diomedea exulans
  • Fisheries
  • Oceanography
  • South Georgia
  • Wandering albatross

ASJC Scopus subject areas

  • Aquatic Science
  • Oceanography

Cite this

Foraging ecology and interactions with fisheries of wandering albatrosses (Diomedea exulans) breeding at South Georgia. / Xavier, J. C.; Trathan, P. N.; Croxall, J. P.; Wood, A. G.; Podesta, Guillermo P; Rodhouse, P. G.

In: Fisheries Oceanography, Vol. 13, No. 5, 09.2004, p. 324-344.

Research output: Contribution to journalArticle

Xavier, J. C. ; Trathan, P. N. ; Croxall, J. P. ; Wood, A. G. ; Podesta, Guillermo P ; Rodhouse, P. G. / Foraging ecology and interactions with fisheries of wandering albatrosses (Diomedea exulans) breeding at South Georgia. In: Fisheries Oceanography. 2004 ; Vol. 13, No. 5. pp. 324-344.
@article{42013a635f6049fe97bc7e43611eb12a,
title = "Foraging ecology and interactions with fisheries of wandering albatrosses (Diomedea exulans) breeding at South Georgia",
abstract = "Knowledge about the areas used by the foraging wandering albatross, Diomedea exulans, its prey and overlap with longline fisheries is important information not only for the conservation of this species but also for furthering our understanding of the ecology of its prey. We attached satellite-tracking devices and activity recorders to wandering albatrosses between May and July of 1999 and 2000 (years of differing food availability around South Georgia) in order to assess inter-annual variation in the main foraging areas, association with oceanographic features (i.e. fronts, bathymetry), diet and interactions with fisheries. The overall foraging patterns of the tracked birds were similar in 1999 and 2000, ranging between southern Brazil (28°S) and the Antarctic Peninsula (63°S) and between the waters off Tristan da Cunha (19°W) and the Patagonian Shelf and oceanic waters south of Cape Horn (68°W) in the South Atlantic. In 1999, wandering albatrosses spent most time in sub-Antarctic oceanic waters, their trip durations were significantly longer and they fed on fish and cephalopods (53 and 42{\%} by mass, respectively). In contrast, in 2000, they spent more time in Antarctic waters, foraging trips were shorter and the diet was predominantly fish (84{\%} by mass). Wandering albatrosses were associated with the sub-Antarctic Front (SAF; both years), Subtropical Front (STF; in 1999) and the Tropical Front (TF; in 2000) suggesting that this species exploits prey concentrated at oceanic fronts. Fisheries discards also seemed to provide a very good source of food. Several fish species that are targeted (e.g. Patagonian toothfish, Dissostichus eleginoides) or are available as offal/discards from commercial fisheries (e.g. the macrourids, Antimora rostrata and Macrourus holotrachys) were mainly associated with the South Georgia shelf and the Patagonian Shelf, respectively. Wandering albatross foraging areas overlapped with longline fisheries in three different regions: around South Georgia, at the Patagonian Shelf and in oceanic waters north of 40°S. Females commuted more frequently to the Patagonian Shelf and to oceanic areas where longline fisheries were operating. Males, on the other hand, spent more time on the shelf/shelf slope of South Georgia where they were more at risk from the local Patagonian toothfish fishery, particularly in 2000. These results emphasize that inter-annual variation in foraging preferences could lead to increased incidental mortality of this vulnerable species. Potential evidence for this is provided by a satellite-tracked wandering albatross (male; 1.8-day trip), whose diet contained a Patagonian toothfish head and a longline hook, and who spent extensive time in the water (44{\%} of the time wet; 0.3 days of the trip) where a Patagonian toothfish longline fishing vessel was operating.",
keywords = "Diet, Diomedea exulans, Fisheries, Oceanography, South Georgia, Wandering albatross",
author = "Xavier, {J. C.} and Trathan, {P. N.} and Croxall, {J. P.} and Wood, {A. G.} and Podesta, {Guillermo P} and Rodhouse, {P. G.}",
year = "2004",
month = "9",
doi = "10.1111/j.1365-2419.2004.00298.x",
language = "English (US)",
volume = "13",
pages = "324--344",
journal = "Fisheries Oceanography",
issn = "1054-6006",
publisher = "Wiley-Blackwell",
number = "5",

}

TY - JOUR

T1 - Foraging ecology and interactions with fisheries of wandering albatrosses (Diomedea exulans) breeding at South Georgia

AU - Xavier, J. C.

AU - Trathan, P. N.

AU - Croxall, J. P.

AU - Wood, A. G.

AU - Podesta, Guillermo P

AU - Rodhouse, P. G.

PY - 2004/9

Y1 - 2004/9

N2 - Knowledge about the areas used by the foraging wandering albatross, Diomedea exulans, its prey and overlap with longline fisheries is important information not only for the conservation of this species but also for furthering our understanding of the ecology of its prey. We attached satellite-tracking devices and activity recorders to wandering albatrosses between May and July of 1999 and 2000 (years of differing food availability around South Georgia) in order to assess inter-annual variation in the main foraging areas, association with oceanographic features (i.e. fronts, bathymetry), diet and interactions with fisheries. The overall foraging patterns of the tracked birds were similar in 1999 and 2000, ranging between southern Brazil (28°S) and the Antarctic Peninsula (63°S) and between the waters off Tristan da Cunha (19°W) and the Patagonian Shelf and oceanic waters south of Cape Horn (68°W) in the South Atlantic. In 1999, wandering albatrosses spent most time in sub-Antarctic oceanic waters, their trip durations were significantly longer and they fed on fish and cephalopods (53 and 42% by mass, respectively). In contrast, in 2000, they spent more time in Antarctic waters, foraging trips were shorter and the diet was predominantly fish (84% by mass). Wandering albatrosses were associated with the sub-Antarctic Front (SAF; both years), Subtropical Front (STF; in 1999) and the Tropical Front (TF; in 2000) suggesting that this species exploits prey concentrated at oceanic fronts. Fisheries discards also seemed to provide a very good source of food. Several fish species that are targeted (e.g. Patagonian toothfish, Dissostichus eleginoides) or are available as offal/discards from commercial fisheries (e.g. the macrourids, Antimora rostrata and Macrourus holotrachys) were mainly associated with the South Georgia shelf and the Patagonian Shelf, respectively. Wandering albatross foraging areas overlapped with longline fisheries in three different regions: around South Georgia, at the Patagonian Shelf and in oceanic waters north of 40°S. Females commuted more frequently to the Patagonian Shelf and to oceanic areas where longline fisheries were operating. Males, on the other hand, spent more time on the shelf/shelf slope of South Georgia where they were more at risk from the local Patagonian toothfish fishery, particularly in 2000. These results emphasize that inter-annual variation in foraging preferences could lead to increased incidental mortality of this vulnerable species. Potential evidence for this is provided by a satellite-tracked wandering albatross (male; 1.8-day trip), whose diet contained a Patagonian toothfish head and a longline hook, and who spent extensive time in the water (44% of the time wet; 0.3 days of the trip) where a Patagonian toothfish longline fishing vessel was operating.

AB - Knowledge about the areas used by the foraging wandering albatross, Diomedea exulans, its prey and overlap with longline fisheries is important information not only for the conservation of this species but also for furthering our understanding of the ecology of its prey. We attached satellite-tracking devices and activity recorders to wandering albatrosses between May and July of 1999 and 2000 (years of differing food availability around South Georgia) in order to assess inter-annual variation in the main foraging areas, association with oceanographic features (i.e. fronts, bathymetry), diet and interactions with fisheries. The overall foraging patterns of the tracked birds were similar in 1999 and 2000, ranging between southern Brazil (28°S) and the Antarctic Peninsula (63°S) and between the waters off Tristan da Cunha (19°W) and the Patagonian Shelf and oceanic waters south of Cape Horn (68°W) in the South Atlantic. In 1999, wandering albatrosses spent most time in sub-Antarctic oceanic waters, their trip durations were significantly longer and they fed on fish and cephalopods (53 and 42% by mass, respectively). In contrast, in 2000, they spent more time in Antarctic waters, foraging trips were shorter and the diet was predominantly fish (84% by mass). Wandering albatrosses were associated with the sub-Antarctic Front (SAF; both years), Subtropical Front (STF; in 1999) and the Tropical Front (TF; in 2000) suggesting that this species exploits prey concentrated at oceanic fronts. Fisheries discards also seemed to provide a very good source of food. Several fish species that are targeted (e.g. Patagonian toothfish, Dissostichus eleginoides) or are available as offal/discards from commercial fisheries (e.g. the macrourids, Antimora rostrata and Macrourus holotrachys) were mainly associated with the South Georgia shelf and the Patagonian Shelf, respectively. Wandering albatross foraging areas overlapped with longline fisheries in three different regions: around South Georgia, at the Patagonian Shelf and in oceanic waters north of 40°S. Females commuted more frequently to the Patagonian Shelf and to oceanic areas where longline fisheries were operating. Males, on the other hand, spent more time on the shelf/shelf slope of South Georgia where they were more at risk from the local Patagonian toothfish fishery, particularly in 2000. These results emphasize that inter-annual variation in foraging preferences could lead to increased incidental mortality of this vulnerable species. Potential evidence for this is provided by a satellite-tracked wandering albatross (male; 1.8-day trip), whose diet contained a Patagonian toothfish head and a longline hook, and who spent extensive time in the water (44% of the time wet; 0.3 days of the trip) where a Patagonian toothfish longline fishing vessel was operating.

KW - Diet

KW - Diomedea exulans

KW - Fisheries

KW - Oceanography

KW - South Georgia

KW - Wandering albatross

UR - http://www.scopus.com/inward/record.url?scp=4544346945&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=4544346945&partnerID=8YFLogxK

U2 - 10.1111/j.1365-2419.2004.00298.x

DO - 10.1111/j.1365-2419.2004.00298.x

M3 - Article

AN - SCOPUS:4544346945

VL - 13

SP - 324

EP - 344

JO - Fisheries Oceanography

JF - Fisheries Oceanography

SN - 1054-6006

IS - 5

ER -