Distribution of albacore (Thunnus alalunga) in the Indian Ocean and its relation to environmental factors
Resource
Fisheries Oceanography 14 (1): 71-80
Journal
Fisheries Oceanography
Pages
71-80
Date Issued
2005
Date
2005
Author(s)
Abstract
The distribution pattern of albacore, Thunnus alalunga, in the Indian Ocean was analyzed based on catch data from the Taiwanese tuna longline fishery during the period 1979-85. The Taiwanese tuna fishery began operating in the Indian Ocean in 1967. We used a geographic information system to compile a fishery and environmental database and statistically explored the catch per unit effort (CPUE) distribution of albacore. Our results indicated that immature albacore were mainly distributed in areas south of 30°S although some displayed a north-south seasonal migration. Mature albacore, which were mainly concentrated between 10°S and 25°S, also showed a north-south migration. Within 10°S and 30°S, the separation of mature, spawning, and immature albacore life history stages roughly coincided with the boundaries of the three oceanic current systems in the Indian Ocean. The optimal environmental variables for CPUE prediction by stepwise discriminant analysis differed among life history stages. For immature albacore, the sea surface variables sea surface temperature (SST), chlorophyll concentration and surface salinity were significant. For mature albacore, SST was significant, while for spawning albacore, the sub-surface variables temperature at 100 m and oxygen at 200 m were significant. Spawning albacore evidently prefer deep oceanographic conditions. Our results on the oceanographic conditions preferred by different developmental stages of albacore in the Indian Ocean were compatible with previous studies found in the Pacific Ocean.
Subjects
Albacore; Current systems; Distribution; Environmental factors; Indian Ocean; Life history stage
SDGs
Other Subjects
catch per unit effort; environmental factor; geographical distribution; migratory behavior; perciform; seasonal variation; catch statistics; chlorophyll; database; discriminant analysis; fish; GIS; population distribution; population migration; sea surface temperature; spawning; tuna fishery; Indian Ocean; oceanic regions; World; Asia; Eurasia; Far East; Taiwan; Scombridae gen. sp.; Thunnus alalunga
Type
journal article
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