The large-scale deployment of fish aggregation devices alters environmentally-based migratory behavior of skipjack tuna in the Western Pacific Ocean.
Fish aggregation devices (FADs) have been used extensively in the tuna purse seine fishery since the 1980s. This long-term modification of natural habitat has generated discussions as to whether FADs impact movement patterns of tuna species. We examined this question using data collected from the skipjack tuna (Katsuwonus pelamis) fishery. We used the longitudinal gravitational center of catch (G) to examine temporal variability in skipjack movement in the Western and Central Pacific Ocean, and related this to El Niño Southern Oscillation (ENSO) events. We found that in most cases G for free-swimming school sets changed with the onset of ENSO events, while G for floating-object-associated school sets remained relatively constant. This suggests that skipjack exhibit distinguishable behavioral strategies in response to ENSO events: they either react by moving long distances or they associate with floating objects. There has been no previous attempt to evaluate the interaction between FADs and the environmentally-determined movement of skipjack; this study shows evidence of an interaction, which should be considered when managing skipjack populations.
College of Marine Sciences, Shanghai Ocean University, Shanghai, China; National Engineering Research Center for Oceanic Fisheries, Shanghai, China; The Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources, Ministry of Education, Shanghai, China.
Xuefang
X
Wang
School of Marine Sciences, University of Maine, Orono, Maine, United States of America; The Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources, Ministry of Education, Shanghai, China.
Yong
Y
Chen
School of Marine Sciences, University of Maine, Orono, Maine, United States of America.
Samuel
S
Truesdell
College of Marine Sciences, Shanghai Ocean University, Shanghai, China; National Engineering Research Center for Oceanic Fisheries, Shanghai, China; The Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources, Ministry of Education, Shanghai, China.
Liuxiong
L
Xu
School of Marine Sciences, University of Maine, Orono, Maine, United States of America.
Jie
J
Cao
College of Marine Sciences, Shanghai Ocean University, Shanghai, China; National Engineering Research Center for Oceanic Fisheries, Shanghai, China; The Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources, Ministry of Education, Shanghai, China.
Wenjiang
W
Guan
D025041:Animal Migration; D000818:Animals; D017753:Ecosystem; D004784:Environmental Monitoring; D005398:Fisheries; D010140:Pacific Ocean; D013997:Time Factors; D014413:Tuna / Q000502:physiology*