452 



Fishery Bulletin 88(3). 1990 



Polydactylus octonemus in the demersal phase have 

 an apparent total annual mortality rate off Texas that 

 approaches 100%, mean time- and cohort-specific 

 values being 97-100%. Only one winter cohort was pre- 

 sent in 31 of 32 months off Freeport (Fig. 6), so time- 

 specific estimates were 100% in each of these instances. 

 Cohort-specific values were 100% in 6 of 7 months for 

 1978, 8 of 8 months for 1979, and 5 of 5 months for 

 1980 fish because A^, was zero. A time-specific esti- 

 mate for April 1979 and a cohort-specific estimate for 

 the 1978 cohort in April of 1978 and 1979 were 75% 

 and 95% (Z=1.39 and 3.00), respectively, but the 

 former value may be an underestimate because the 

 younger cohort was incompletely recruited in April. 



o 



12 

 10 



8 



6 



4 



2 H 

 



• 1979 

 D 1980 

 ^ 1981 



M 



n 1 r 



M J J 

 MONTH 



A 



O 



Figure 12 



Catch/effort (mean number/10-min tow) by month o{ Polydncfylux urdmemus 

 off Freeport, Texas, each year. 



