AACL Bioflux, 2016, Volume 9, Issue 3. http://www.bioflux.com.ro/aacl 741 Growth and mortality parameters of yellowfin tuna ( Thunnus albacares ) in Palabuhanratu waters, west Java (eastern Indian Ocean) 1,2 Erfind Nurdin, 2 Muhamad F. A. Sondita, 2 Roza Yusfiandayani, 2 Mulyono S. Baskoro 1 Research Institute for Marine Fisheries - Ministry of Marine Affairs and Fisheries, Jakarta, Indonesia; 2 Department of Fisheries Resources Utilization, Faculty of Fisheries and Marine Sciences, Bogor Agricultural University, Darmaga – Bogor, Indonesia. Corresponding author: E. Nurdin, erfind_nurdin@yahoo.co.id Abstract . Growth and mortality parameters were estimated for the yellowfin tuna ( Thunnus albacares - Bonnaterre, 1788). A total of 2,906 individuals were sampled from the types of small scale commercial vessel units operating five fishing gears (troll line, hand line, floating line, vertical line and kite line) around fish aggregating devices (FADs) in the Palabuhanratu waters (eastern Indian Ocean) from April to December 2015. The aims of this study were to estimate the growth and mortality rate. The data were analyzed by using FiSAT II. The von Bertalanffy growth parameters were estimated at L ∞ = 178 cm fork length (cmFL), k= 0.47 year -1 , and t 0 = -0.213 year. The total mortality rate (Z) estimated was 1,27 year - 1 , with the natural mortality rate (M) and fishing mortality rate (F) of 0.66 year -1 and 0.61 year -1 respectively. The exploitation rate (E) was estimated to be 0.48. This condition indicates that exploitation of the yellowfin tuna is still in good condition and it is necessary to manage the fishing pressure on the stock to prevent the probability of overfishing events. Key Words: overfishing, tuna fishing, fishing management, commercial fishing. I ntroduction . Fisheries resources are a common property where the exploitation can be used by more than one individual at the same time (open access). Tuna resource utilization from year to year tends to increase. While impact in long-term, will affect to the continuity of fish stock. Therefore, a management concept for controlling the sustainable yield is needed. ISSF technical report (2012) states that global catches for tuna; albacore, bigeye, bluefin, yellowfin and skipjack in year 2010 amount to 4.34 million tons, decrease 4% from 2009. Tuna catches from 1950 tend to increase steadily since the early 2000s. Yellowfin and bigeye tuna stock in Indonesia waters is estimated in fully exploited condition and overfished in some areas (Langley et al 2009a; IOTC 2010; WCPFC 2010; Harley et al 2011). The increase in catch production and the development of fishing effort has led to the decline of the size of resources. If the size were narrowed, the number of chance for tuna to spawn will be reduced, and this will inflict the recruitment of overfishing. Management of fisheries resources should be based on the precautionary approach principle, for the protection of resources and environmental conservation. The implementation of the precautionary approach is an alternative to the provisions of United Nations Convention on the Law of the Sea (UNCLOS) in 1982 that requires the results of the best scientific evidence available for the management and conservation of fish resources. The aims of this study are to estimate the growth and mortality rate of yellowfin tuna. These factors have an affect on population dynamics, thought to predict the pattern of population growth and as basic data in fisheries management.