FISHERY BULLETIN; VOL. 87, NO. 4, 1989 



UFL) (Student's t-iest; P < 0.05). Not all hard- 

 parts were collected from all fish. For a break- 

 down offish size ranges and hardparts collected, 

 the reader is referred to Table 1. 



Hardpart Growth 



The relationships between AR, DR, and CD, 

 and LJFL were best described by significant (P 

 < 0.001) positive hnear equations (Table 2). 

 Coefficient of determination values ranged from 

 r^ = 0.19 for male vertebrae to r = 0.72 for 

 female anal spines (Fig. 1). The relationships 

 between SW and LJFL were exponential, with 

 r = 0.41 for males and r^ = 0.35 for females 

 (Table 2, Fig. 2). Logarithmic equations best 

 described the relationships between AR, DR, 

 CD, and W for both sexes (Table 2). Coefficient 

 of determination values were significant (P < 

 0.001), ranging from r = 0.30 for male verte- 

 brae to r^ = 0.87 for female dorsal spines. 

 Sagitta weight had a linear relationship with W, 

 with r = 0.32 for males and c^ = 0.46 for 

 females. 



Overall, there were generally higher coeffi- 



cients of determination between AR, DR, CD, 

 and W compared with those with LJFL. In addi- 

 tion, females generally had stronger relation- 

 ships between hardpart size and body size 

 (LJFL and W) when compared to males, the 

 exception to this being the relationship between 

 female SW and UFL. 



Growth Increments 



Thin cross sections of dorsal and anal fin 

 spines revealed a vascularized core matrix and a 

 cortical region containing major growth bands 

 (Fig. 3). A growth band was composed of alter- 

 nations of ti'anslucent and opaque rings. Many 

 growth bands were comprised of smaller rings 

 that were most obvious at the widest lateral 

 portion of the spine section (Fig. 4). Since band 

 radii were measured from the focus outward 

 along the widest portion of the spine, excessive 

 numbers of smaller rings along the counting path 

 made delineation of the outside edge of the 

 translucent zone difficult at times, especially in 

 exceptionally large spine samples. In such cases, 

 it was necessary to refer to the dorsal and ven- 



Table 2 — Modeled relationships between fish growth (in length and weight) and 

 hardpart growth for male and female Pacific Makaira nigricans. LJFL = lower 

 jaw-fork length, W = roundweight, AR = anal spine radius, DR = dorsal spine 

 radius, SW = sagitta weight, CD = centrum cone depth. 



832 



