346 



FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



"^'^^i^^t 



Figure 2. — Modern Gulf of Mexico "offshore" shrimp trawler. (This vessel was built in 1958, is 57 ft. long, has a capacity 



of 55 gross tons, a 150-horsepower engine, and is double-rigged.) 



ticipating in inshore commercial fisheries are 

 small, shallow-draft, low-powered boats of less 

 than 5 tons net capacity. Most recent estimates 

 place their number between three and four 

 thousand. 



Although shallow-draft like their inshore 

 counterparts, shrimp trawlers (fig. 2) plying 

 offshore waters are more sturdily constructed, have 

 greater internal capacity, and are fitted with cor- 

 respondingly larger power plants. The average 

 sea-going trawler, qualified by an indication of 

 slight increase in size during the period 1956-59, 

 has a register length of about 57 feet, an internal 

 capacity of 50 gross tons, and a power plant 

 rated at 160 horsepower. Significantly, such 

 specifications vary within rather narrow limits for 



a high proportion of the United States offshore 

 fleet, wliose size is estimated at between four and 

 five thousand vessels. 



Gulf shrimp trawlers (figs. 2, 3, 4) may be 

 equipped with only the most essential and siniplest 

 of navigational devices. Smaller vessels (shorter 

 than 45 feet) ordinarily possess no electronic aids, 

 but many larger craft are fitted with radio- 

 telephones, fathometers, automatic pilots, and 

 radio navigation equipment. Radar, loran, and 

 fish-finding devices will be found only on the 

 largest trawlers. 



Following a period of transition (1955-57), 

 trawler rigging througiiout the oflfshore fleet is 

 now quite uniform. Whereas every vessel prior 

 to 1956 was rigged to pull a single large trawl 



