19 



pounds) was about the same as during the 

 night (278 pounds), but the early morning 

 drags were considerably less productive (112 

 pounds). Carp comprised a larger portion 

 of the late afternoon catch than at either of 

 the other time periods, Carpsuckers were 

 about the same percentage of the catch dur- 

 ing all periods; buffalofish were a larger part 

 of the early morning and nighttime catches 

 than during the late afternoon; and goldeye 

 made up over 2 perdent of the catch only at 

 night. 



Commercial production drags: 44 drags 

 were made to catch commercial species in 

 the largest quantity possible. Results are 

 analyzed on the quantity of fish taken per 

 standard 15-minute drag and on "operational 

 hours": i.e., hours required to complete 

 trawling in a local area. Operational hours 

 reflect shooting, dragging, and hauling time, 

 time spent in cruising from one drag site to 

 another in a localized area, and delays re- 

 sulting from minor or routine maintenance 

 of gear. Operational hours do not include the 

 time required for travel from one major 

 trawling area to another. 



Most of one day was spent trawling in a 

 "marginal production area" (upper Zone 4), 

 Drag sites here consist of small scattered 

 bays, so considerable time was lost in travel 

 from one drag site to another. Seven opera- 

 tional hours produced only 70 trawling min- 

 utes. The take of com.mercially saleable fish 

 was 65 pounds per 15-minute drag, or 43 

 pounds per operational hour. The commer- 

 cially saleable poundage was: 84 percent 

 carp, 10 percent river carpsucker, 5 percent 

 bigmouth buffalo, and 1 percent channel cat- 

 fish. ("Commercially saleable" are species 

 designated commercial by the State, and are 

 such species and sizes the local industry can 

 sell.) All the bigmouth buffalo and 86 percent 

 of carpsuckers were commercial size, but 

 only 67 percent of catfish and 34 percent of 

 carp were that large. 



Twenty-four operational hours (560 trawl- 

 ing minutes) were spent on a prime trawling 

 area in Zone 6. The catch of commercially 

 saleable fish was 89 pounds per 15-minute 

 drag, or 137 pounds per operational hour. 

 The commercial poundage was 55 percent 

 bigmouth buffalo, 38 percent carp, 3 percent 

 smallmouth buffalo, 2 percent river carp- 

 sucker, 1 percent goldeye, and 1 percent 

 freshwater drum and channel catfish com- 

 bined. Nearly all buffalofish and goldeye. 



two -thirds of channel catfish, one -fourth of 

 carp and carpsuckers, and 8 percent of drum 

 taken were commercial size. 



Young-of-the-year and yearling catch: Of 

 3,370 young-of-the-year fish taken, 90 percent 

 were black bullheads, 5 percent drum, and 4 

 percent crappies. Other species taken, each 

 less than one percent of catch, were white 

 bass, perch, and walleye. 



Of 18,360 yearling fish taken, 92 percent 

 were black bullheads, 4 percent were crap- 

 pies, and 2 percent were yellow perch. Other 

 yearling fish taken, but each species less than 

 one percent of total number, were: sauger, 

 white bass, goldeye, northern pike, walleye, 

 channel catfish, carp, bigmouth buffalo, small - 

 mouth buffalo, freshwater drum , and burbot. 



Note: For more information, contact: Base Director, Exploratory 

 Fishing Base, BCF, 5 Research Drive, Ann Arbor, Mich. 48103, 



Gulf Fisheries Explorations and 

 Gear Development 



"BOWERS" ELECTRIC SHRIMP TRAWLS 

 ARE SUCCESSFUL 



Daytime catches with the electrical shrimp 

 trawl are about equal to nighttime catches with 

 the standard trawl, cruise 67 of the George M, 

 Bowers shows. The gear research vessel 

 recently completed an electric shrimp-trawl- 

 ing cruise off Mississippi and Texas, Two 

 simultaneously towed 40 -foot Gulf of Mexico 

 flat trawls were used. The starboard trawl 

 was equipped with components of the electri- 

 cal system; the port trawl with a single tickler 

 chain. Comparison tows lasted one hour. 



Daytime electric trawl catches averaged 

 96 percent of the night non-electric trawl 

 catches. The weight averages of the catches 

 were 15.5 Ibs./hr. for the daytime electric 

 trawl--and 16.2 Ibs./hr. for the night non- 

 electric trawl. The day non-electric average 

 was 0.5 Ibs./hr, --and the night electric aver- 

 age was 9.9 lbs,/hr. The researchers are 

 trying to take underwater motion pictures of 

 the electrical trawl while fishing. If success- 

 ful, the films should explain the lower catch 

 rates of the electrical trawl at night. 



An efficiency of 96% for the daytime elec- 

 trical trawl, compared to the night standard 



