"....it munt be remembered that even the catch of tv;o 



boats made at the sa?ne time and in the same /general area cannot be com- 

 pared vjith confidence for one boat may pass throu,p:h the school and the 

 other may miss it entirely." 16/ 



Naturally, the largo r the amount of data that can be collected 

 on comparable operations, the less important becomes the element of 

 chance. Certain relationships beti;een technological, geographical and 

 other factors and vessel productivity can be discovered if catch informa- 

 tion from an adequate sample oC vessels fishing the same vxaters at the 

 same time is obtained, • 



On the basis of limited sample obseirvations, Harwell, Knovles 

 and Associates relate such factors as length and pouer of vessel, 

 seasonality, geographical location of fishery, and owner-operation to 

 vessel productivity. 



Table III- 9 furnishes some clues to what extent geograpliical 

 differences between fishing grounds influence size of catch. Average 

 annual catch for vessels in the sample ranged from 12,9J4i4 pounds for 

 vessels operating out of Mayport, Florida, to as much as 82,6o6 pounds 

 for Brownsville, Texas, operations. Average catch per day was as low 

 as 82 pounds, and as high as 372 pounds. 



There is a clear indication that average annual catches of 

 vessels operating out of south Atlantic ports are substantially below 

 those made by boats fishing in the Gulf. This difference betA-ieen the 

 two areas is in part accounted for by the shorter fishing season in the 

 vfaters of the Atlantic. Boats out of Rockville, South Carolina, fished 

 on the average only on lilt days as compared to vessels operating in the 

 Gulf where the season extended anyirhere from 2l5 to 237 days, Campeche 

 operations conducted out of Tampa, Florida, and Brovmsville, Texas, were 

 by far the most productive. These operations ;jith few exceptions are re- 

 stricted to the larger, more exi^ensive boats. In the case of the vessels 

 engaged in the Campeche fishery, trips are more hazardous and running 

 costs much higher than elsewhere. 



Seasonal characteristics of shrimp catches in the Thunderbolt, 

 Georgia; Key West, Florida', Biloxi, Mississippij and Brownsville, Texas, 

 fisheries are illustrated in table III -10. Average annual catches of 

 boats in the Tortugas operations (operating out of Key West) were fairly 



16/ Henry H. Hildebrand, A St udy of the Faima o f _the Brown Shrimp 



Grounds in t he Ues tern GiUf of Me xico, publTcafgons of the Institute 

 of Marine Science, "Volume III, No. '2, November, 191?1+. 



157 



