Table 4. — Catch (pounds and percentage) and (in parentheses) percentage com- 

 position of the catch in 14 seine hauls in Sandusky Bay, April-November 1969. 



-'Tr - <0.5%. 



estimated weight for each species and of the 

 estimated weight or percentage of each that 

 was discarded. Errors in estimation were min- 

 imized by comparing the tallies of estimated 

 landings with the quantities of boxed fish. As 

 a further check (for trap net catches only), the 

 actual weight of the landed catch of each species 

 recorded in the fish house at the end of the day 

 was compared with the poundage estimated by 

 the observer. The percentage error in the esti- 

 mated catches ranged from + 10 9f to — 16% 

 for individual trips; however, the total weights 

 of the estimated landings from all 13 series of 

 trap net lifts combined averaged only 4% above 

 the actual landings. 



Errors in estimation for seine catches could 

 not be readily checked because the landings from 

 more than one seine haul were often combined 

 and reported as a day's catch. Estimates by 

 observers of the landed and discarded portions, 

 however, were compared with estimates by an 

 experienced foreman to corroborate the pound- 

 age estimates for each haul observed. 



Haul 



seine estimates 



Catch data wei'e collected at one of the San- 

 dusky Bay seining grounds every two or three 



weeks fi'om April to November 1969. Esti- 

 mated weight of a haul seine ranged from a low 

 of 1,372 lb (July 28) to a high of 14,250 lb 

 (.June 23). A total catch estimate of 8.5,871 lb 

 was recorded for the 14 seine hauls, with an 

 average of 6,134 lb (Table 4). Weight of the 

 landed fish averaged 3,525 lb per haul (57C; of 

 the total catch) and the discarded portion, 2,609 

 lb (43% ) . Some of the discards, however, were 

 fish of high- and medium-value species that were 

 released because they were below legal size. 

 When undersized fish were excluded, the discard- 

 ed catch that could have been legally kept aver- 

 aged 2,252 lb per haul — or about 37% of the 

 haul seine catches. 



Low-value species made up 91 ''r of the total 

 catch by haul seines — 94 "^r of the landed catch 

 and an estimated 86% of the discarded catch 

 (Fig. 6). Freshwater drum made up most of 

 the total catch and landed catch (Table 4). Gold- 

 fish and carp also contributed significantly to the 

 total catch. Carp were not as abundant as gold- 

 fish in the total catch but contributed a higher 

 portion of the landed fish because of the greater 

 marketability of carp. 



Medium-value fishes provided over 9''^ of the 

 total catch from the bay area — 6% of the landed 

 fish and 14''r of the estimated weight of dis- 



