Age determination and growth estimation from otolith micro-increments and fin spine sections of blue marlin (Makaira nigricans) in the western North Pacific

作者：Shimose Tamaki^*; Yokawa Kotaro; Tachihara Katsunori

来源：Marine and Freshwater Research, 2015, 66(12): 1116-1127.

DOI：10.1071/MF14305

• billfish
• Istiophoridae
• sexual dimorphism

Age determination and growth estimation of blue marlin (Makaira nigricans) were performed by combining method of otolith micro-increment counts of 27 young (17-185-cm lower jaw-fork length, LJFL) and sectioned dorsal fin spines of 571 adult individuals (155-352cm). Otolith micro-increments were counted with ages of 26-338 days old. The estimated mean length (185cm) at Year 1 and growth rate were used to predict the position of the first annual growth band in sectioned fin spines. Distinct growth bands were formed in fin spines annually between September and October. Indistinct growth bands were considered false-annual growth bands. The observed and back-calculated LJFLs at each age were highly variable for both sexes. Von Bertalanffy growth parameters were estimated using mean back-calculated LJFL data as: L=295cm, k=0.23, t(0)=-3.31 years for females and 212cm, 0.29, -4.49 years for males. Females grew to >200cm in 2 years and to >250cm in 5 years on average, whereas the growth of males slowed appreciably after they reached the age of 1 year. This is the first study of blue marlin growth for entire life stages.

• 出版日期2015