STANDARDIZING CPUE OF ALBACORE TUNA (Thunnus alalunga Bonnaterre, 1788) ON TUNA LONGLINE FISHERY IN EASTERN INDIAN OCEAN
Abstract: Albacore (Thunnus
alalunga) is the third dominant catch of Indonesian tuna longline fishery
operating in the eastern Indian Ocean. The percentage production of albacore
catch was reaching up 6% of the total catch of tuna groups in Indonesia. Thi
study aims to examine a relative abundance indices using standardized catch per
unit of effort (CPUE) of longliner based on albacore tuna. This information
will give a valuable input and information to support stock assessment
particularly in the regional basis. In this study, we use Generalized Linear
Model (GLM) with Tweedie distribution to standardize the CPUE and to estimate
relative abundance indices based on the Indonesian longline dataset time
series. Data were collected from January 2006 to October 2015 (106 trip
observer and 8.989 fishing days) by conducting direct onboard observation on
tuna longline vessels operating in the Indian Ocean. The result show that year,
area,hooks between floats, year*season, year*area and year* hooks between
floats significantly influenced the nominal CPUE of albacore. The highest value
of Standardized CPUE appeared in 2014 and probably related to the large number
of foreign fishing vessels with a high capacity (over 60 GT) targeting frozen
tuna including albacore. In 2015, standardized CPUE value was sharply decreased
due to the ban of foreign vessels in Indonesia.
Keywords: Standardization;
albacore; generalized linear model; Indian Ocean
Author: Fathur Rochman, Bram
Setyadji, Arief Wujdi
Journal Code: jpperikanangg170019