Dentzau and Chittenden: Population dynamics of Polydactylus octonemus in the Gulf of Mexico 



445 





W80 



21 Mar 80 D 

 n=1 



n 1 r 



^W80 0^ 



5 May 80 N 

 n=58 



T 1 r 



5n 



^W80-0 — 



19 May 80 D 

 n=45 



W80,( 



— W80 0- 



19 Jun80D 

 n=22 



— ^ 



-W80 



I*- 



11 Jul SON 

 n=209 



-W800- 



.,.,A.^^.„ 



24 Jul 80 D 

 n=121 



10-| 



5- 



T ' r 



— W80 0- 



Y^-' 



5-1 11 Sep SON 

 n=35 



-W80 0^ 



5i 25 Sep 80 

 n=36 



— I 1 1 r 



6 Oct 80 N 



n=4 



^W80 0- 



W80 



6n 21 Oct 80 D 



n=1 



W80 



6 Nov 80 Nl 

 n=1 



W810 



W81 



n ' 1 



20 Api81 D 

 n=1 



60 



— I — 

 180 



240 300 



^W810^ 



4 May 81 N 



n=31 



T 1 r 



2Jun80N lOn 



n=6 



W81  



W81,0 . 



19 May 81 D 

 n=54 



-I—' 



7 Jiin81 N 

 n=133 



1-^^^ I 

 . W81 • 



16 Jun81 D 

 n=127 



^WBIO- 



T ' 1 



1 Jul 81 N 

 n=165 



AQ, - 



13 Aug 80 N lO- 



n=182 



W81 0- 



20 Jul 81 

 n=342 



307 



20 



10 



^W81 0- 



3 Aug 81 D 

 n=566 



20 1 



15- 



10 



5- 



20 Aug 81 D 

 n=395 



W81,0 . 



Apr 81 N 10 



n=2 



1 ' 1 



18 May 82 D 

 n=219 



120 180 240 300 



TOTAL LENGTH (mm) 



Figure 6 

 (continued) 



Polydactylus octonemus primarily spawn in one dis- 

 crete period from mid-December through mid-March. 

 The well-defined modes in length frequencies from 

 throughout the study (Fig. 6) suggest spawning oc- 



curred in one discrete period. Major spawning must 

 have occurred during mid-December-mid-March, 

 because small, young fish recruited mainly during mid- 

 March-mid-May each year, e.g., fish 75-105 mm and 



