Table 2. — Weekly retail and wholesale value and poundage of bait shrimp 

 caught in Old Tampa Bay, December 4, 1961, through April 8, 1962 



seven boats per day in lower Tampa Bay 

 and less than one boat per day in Old Tampa 

 Bay. About 184 more shrimp were produced 

 per boat-hour in lower Tampa Bay than in 

 Old Tampa Bay (tables 3 and 4). 



Catches consisted almost entirely of pink 

 shrimp. One other penaeid species, Trachy- 

 peneus constrictus (Stimpson), occurred rarely 

 and was usually not marketed. This species 

 was sorted from our samples before the pink 

 shrimp were measured. 



The size of the bait shrimp catch varied 

 considerably during the sampling period. In 

 lower Tampa Bay it ranged from 91,400 to 

 360,720 individuals weekly (table 3), and in 

 Old Tampa Bay the range was from 6,000 to 

 31,000 (table 4). During months of greatest 

 abundance (October- February), the catch of 

 shrimp depended mainly on weather and 

 tides. Cold fronts and accompanying inclement 

 weather were frequent during this period. 

 Furthermore, low tides at this time of 

 the year often drain large portions of the 

 shrimping areas. Fortunately for shrimpers, 

 the tides are generally nnore favorable at 

 night, when the shrimpers do all of their 

 fishing. 



BIOLOGICAL CHARACTERISTICS OF BAIT 

 SHRIMP 



Sex Ratio and Size Differences 



Pink shrimp examined totaled 11,695 of 

 which 79.3 percent came from lower Tampa 

 Bay. The sex ratio varied among samples 

 and areas, but averaged nearly 1:1; females 

 showed only a slight predominance (table 5). 

 These findings correspond to those of Tabb, 

 Dubrow, and Jones (1962) in Everglades Na- 

 tional Park, Fla., and Eldred, Ingle, Woodburn, 

 Hutton, and Jones (1961) in Tampa Bay, Fla. 



The mean carapace length of female shrimp 

 was larger than that of males in all except one 

 collection (tables 6 and 7). This inequality 

 confirmed observations by Eldred et al.(196l) 

 on Tampa Bay shrimp. In their samples, 

 females were more abundant than nnales above 

 85 mm. in total length. Weymouth, Lindner, 

 and Anderson (1933) found that in Penaeus 

 setiferus the size difference between sexes 

 increased with age and was clearly evident 

 after the majority of individuals reached the 

 total length of 130 mm. Williams (1955) de- 

 tected no significant difference in size 



