<5-* 



5.1 cm X 7.6 cm 

 WOODEN STAKES 



Figure 1.— Top trotline. 



1 cm X 7.6 cm 

 WOODEN STAKES 



Figure 2. — Bottom trotline. 



commonly used baits by commercial trotline fish- 

 ermen (McEachron et al. 1980, 1986). 



Fishes caught were identified (Hoese and 

 Moore 1977; Robins et al. 1980), counted (Table 

 1), and total length (TL) was measured to the 

 nearest 1 mm. Data were pooled into fall (Septem- 

 ber-November), winter (December-February), 

 spring (March-May), and summer (June-Au- 

 gust) to examine seasonal variation. 



A catch rate (No. /line • h) for black drum; red 

 drum; spotted seatrout; hardhead catfish Arius 

 felis ; and total fishes was computed for each trot- 

 line set by dividing the number caught by the 

 number of hours fished. Catch rates were trans- 

 formed to log (catch rate + 1) and analyzed using 

 a four-factor fixed-effects model analysis of vari- 

 ance (AOV). The four factors were 1) hook place- 



ment, at two levels — top and bottom; 2) bait, at 

 three levels — crab, shimp, and leaves; 3) bay, at 

 two levels — upper Laguna Madre and lower La- 

 guna Madre; 4) season, at four levels — fall, win- 

 ter, spring, and summer. 



Diff'erences in main effect means were evalu- 

 ated with Ducan's multiple range test. However, 

 when significant first-order interactions were 

 found, comparisons were made within levels of 

 the interacting factors using the mean square 

 error (MSE) from the AOV. 



Total lengths of each species were analyzed in 

 a nested AOV to investigate differences among 

 the four factors. However, because fish were not 

 caught in all factor level combinations, factors 

 and/or factor levels for each species were elimi- 

 nated from analyses. Spotted seatrout lengths 



110 



