FISHERY BULLETIN: VOL. 80, NO. 4 



during winter months, when inshore waters of 

 the South Atlantic Bight have their annual 

 minimum values (Table 1). They were absent in 

 55 trawl tows made during winter in the 9-18 m 

 depth zone and showed variable frequencies of 

 occurrence in other seasons in comparable 

 depths. 



A trend for an increase in modal length with 

 increasing trawl depth was apparent (Fig. 2). All 

 specimens <24 cm FL were encountered in 

 depths <56 m. 



Table 1.— Catch/tow values from whiteboneporgies, Calamus 

 leueosteus, from stratified random research surveys from 1973 

 to 1977. >h = number of trawl tows which contained C. 

 leueosteus: n = total trawls in depth zone. 



Depth zone (m) 



Season 



Catch/tow 



9-18 19-27 



28-55 56-110 



Winter x catch/tow number 4.0 2.0 7 



x catch/tow weight (kg) 1.23 1.07 0.43 



n,ln 0/55 13/50 9/66 4/42 



Spring x catch/tow number 0.3 1.4 3 1.3 



x catch/tow weight (kg) 03 0.55 0.10 103 



n,ln 2/22 5/20 4/28 4/18 



Summer x catch/tow number 4.3 2.6 3.1 0.6 



x catch/tow weight (kg) 1.12 1.02 1.65 0.43 



n,/n 9/48 10/50 16/66 5/41 



Fall x catch/tow number 2.7 2.6 0.8 0.6 



x catch/tow weight (kg) 0.82 1.08 0.24 0.52 



n,/n 4/18 4/18 3/19 2/14 



30 

 20 



IO 





 40 



<fl 30 



< 



3 20 



o 



> IO 



a 



U. 40 -| 

 O 



ir 30 



9-l8m 



x = 2l 

 n = 252 



i i i 



l9-27m 

 1=24 

 n= 406 



III!. 



I .11, III! 



I.I 



20 - 



CD 



2 

 => 

 Z IO 





 20 



10 



28-55m 

 * = 26 

 n= 363 



,.1. . ..Illlllll 



ll 



56-IIOm 

 3= 30 

 n = 86 



i i i i | i i i i | i i i i | i i i i | i i i I ) I 



5 10 15 20 25 30 



FORK LENGTH (cm) 



I ! 1 | I I m | m i I | I I M | 



35 



40 



45 



50 



FIGURE 2.— Length-frequency distribution of Calamus leu- 

 eosteus by depth zone for 3/4 Yankee trawl caught specimens 

 (1973-77). 



Age and Growth 



Life history information was obtained from 

 1,732 fish collected from 1975 to 1980. Age deter- 



minations were attempted for 1,664 pairs of oto- 

 liths and 1,679 scale samples, and of these, 80% of 

 the otoliths and 45% of the scales showed discern- 

 ible rings. There was a 62.8% 1:1 agreement in 

 ages obtained from both scales and otoliths from 

 760 individuals. 



Mean marginal increments by month for 

 scales and otoliths were examined to determine 

 the time of annulus formation (Fig. 3). Samples 

 were combined by month regardless of the year 

 of capture. Mean marginal increments should 

 approach zero at the time of annulus formation; 

 this occurs in June on scales and in July on 

 otoliths. 



Fork lengths increased with increasing age as 

 shown by scales and otoliths (Table 2); however, 

 this progression was obscured in older age 

 groups by smaller sample sizes. In general, 

 average fork lengths derived from scale age and 

 otolith age were similar for the first few years, 

 then fish aged by otoliths tended to be smaller- 

 then those aged by scales. Fish given identical 

 ages using both scales and otoliths showed 

 average fork lengths at age similar to those 

 derived by scales alone. 



The relationships of fork length to otolith and 

 scale radius were best described by the equations 



logFL = 1.041 +0.844 log OR 

 n= 1,320 r 2 = 0.70 



5 

 4 



§ 3H 



z 



=> 2 



o 



(133) 



(166) 



(71) 



I 





 35-i 

 30- 



tr 25 

 o 



z 



- 20-| 



_i 



I 15- 

 1 I0J 



(94) 



SCALES 



(252) 



O 



(l) 



O O All ages 



• • Ages l-ll 



-I 1 1 1 1 1 1 1 1 1 1 I 



JFMAMJJASOND 



MONTHS 



Figure 3.— Mean marginal increments for otoliths and scales 

 by month for Calamus leueosteus. Number in parentheses = 

 sample size. 



866 



