Length-length and Length-weight relationship of bullet tuna (Auxis rochei) and frigate tuna (Auxis thazard) from the coastal of west Sumatra, Indonesia

The length-weight relationship (LWR) and length-length relationship (LLR) have been applied for basic uses in order to make fish stocks and population assessment. The aims of this paper were to provide the baseline information of the length-length relationship and the length-weight relationship of A. rochei and A. thazard collected from the coastal of west of Sumatra. The samples were collected from several landing ports around west of Sumatra, i.e. Lampulo. Sibolga, Padang, Bengkulu, and Lampung. A total of 722 bullet tuna and 707 frigate tuna were measured (FL and TL) and weighed during the study. The relationship between length was determined using linear regression, whereas the length-weight relationship was done by using power regression. The equation (FL-TL. FL-W, TL-W) were reliable with R2 close to 1. The bullet tuna and frigate tuna from all port samplings were hyperallometric.