TY - JOUR
T1 - Global trophic ecology of yellowfin, bigeye, and albacore tunas
T2 - Understanding predation on micronekton communities at ocean-basin scales
AU - Duffy, Leanne M.
AU - Kuhnert, Petra M.
AU - Pethybridge, Heidi R.
AU - Young, Jock W.
AU - Olson, Robert J.
AU - Logan, John M.
AU - Goñi, Nicolas
AU - Romanov, Evgeny
AU - Allain, Valerie
AU - Staudinger, Michelle D.
AU - Abecassis, Melanie
AU - Choy, C. Anela
AU - Hobday, Alistair J.
AU - Simier, Monique
AU - Galván-Magaña, Felipe
AU - Potier, Michel
AU - Ménard, Frederic
N1 - Publisher Copyright:
© 2017 Elsevier Ltd
PY - 2017/6
Y1 - 2017/6
N2 - Predator-prey interactions for three commercially valuable tuna species: yellowfin (Thunnus albacares), bigeye (T. obesus), and albacore (T. alalunga), collected over a 40-year period from the Pacific, Indian, and Atlantic Oceans, were used to quantitatively assess broad, macro-scale trophic patterns in pelagic ecosystems. Analysis of over 14,000 tuna stomachs, using a modified classification tree approach, revealed for the first time the global expanse of pelagic predatory fish diet and global patterns of micronekton diversity. Ommastrephid squids were consistently one of the top prey groups by weight across all tuna species and in most ocean bodies. Interspecific differences in prey were apparent, with epipelagic scombrid and mesopelagic paralepidid fishes globally important for yellowfin and bigeye tunas, respectively, while vertically-migrating euphausiid crustaceans were important for albacore tuna in the Atlantic and Pacific Oceans. Diet diversity showed global and regional patterns among tuna species. In the central and western Pacific Ocean, characterized by low productivity, a high diversity of micronekton prey was detected while low prey diversity was evident in highly productive coastal waters where upwelling occurs. Spatial patterns of diet diversity were most variable in yellowfin and bigeye tunas while a latitudinal diversity gradient was observed with lower diversity in temperate regions for albacore tuna. Sea-surface temperature was a reasonable predictor of the diets of yellowfin and bigeye tunas, whereas chlorophyll-a was the best environmental predictor of albacore diet. These results suggest that the ongoing expansion of warmer, less productive waters in the world's oceans may alter foraging opportunities for tunas due to regional changes in prey abundances and compositions.
AB - Predator-prey interactions for three commercially valuable tuna species: yellowfin (Thunnus albacares), bigeye (T. obesus), and albacore (T. alalunga), collected over a 40-year period from the Pacific, Indian, and Atlantic Oceans, were used to quantitatively assess broad, macro-scale trophic patterns in pelagic ecosystems. Analysis of over 14,000 tuna stomachs, using a modified classification tree approach, revealed for the first time the global expanse of pelagic predatory fish diet and global patterns of micronekton diversity. Ommastrephid squids were consistently one of the top prey groups by weight across all tuna species and in most ocean bodies. Interspecific differences in prey were apparent, with epipelagic scombrid and mesopelagic paralepidid fishes globally important for yellowfin and bigeye tunas, respectively, while vertically-migrating euphausiid crustaceans were important for albacore tuna in the Atlantic and Pacific Oceans. Diet diversity showed global and regional patterns among tuna species. In the central and western Pacific Ocean, characterized by low productivity, a high diversity of micronekton prey was detected while low prey diversity was evident in highly productive coastal waters where upwelling occurs. Spatial patterns of diet diversity were most variable in yellowfin and bigeye tunas while a latitudinal diversity gradient was observed with lower diversity in temperate regions for albacore tuna. Sea-surface temperature was a reasonable predictor of the diets of yellowfin and bigeye tunas, whereas chlorophyll-a was the best environmental predictor of albacore diet. These results suggest that the ongoing expansion of warmer, less productive waters in the world's oceans may alter foraging opportunities for tunas due to regional changes in prey abundances and compositions.
KW - Classification trees
KW - Climate changes
KW - Ecosystems
KW - Food webs
KW - Inter-ocean comparison
KW - Macroecology
KW - Meta-analysis
KW - Trophic relationships
UR - http://www.scopus.com/inward/record.url?scp=85018765258&partnerID=8YFLogxK
U2 - 10.1016/j.dsr2.2017.03.003
DO - 10.1016/j.dsr2.2017.03.003
M3 - Artículo
SN - 0967-0645
VL - 140
SP - 55
EP - 73
JO - Deep-Sea Research Part II: Topical Studies in Oceanography
JF - Deep-Sea Research Part II: Topical Studies in Oceanography
ER -