Figure 7. — Provisional ranges of Tortugas and south 

 Sanibel pink shrimp stocks. 



frequent an area extending at least to release sites 

 13, 14, 6, 2, 9, 3, and 7 (fig. 2). From the south 

 section of the Sanibel grounds (13), two marked 

 shrimp moved southward to the northwest portion 

 of the Tortugas trawling area, establishing a 

 degree of affiliation between these two fisheries. 

 Because many juvenile shrimp released in Pine 

 Island Sound (10) migrated to the Sanibel shrimp 

 fishery, the relationship of Pine Island Sound 

 shrimp to the Tortugas stocks is also indicated. 

 A total of 35,409 marked shrimp released on Sani- 

 bel and in Pine Island Sound, however, yielded 716 

 recoveries in the Sanibel fishery and only two 

 recoveries to the south, on the Tortugas grounds. 

 Therefore, contribution of shrimp from these two 

 northern sites to the Tortugas fishery must be 

 considered minimal. 



Indian Key (14) is about 55 miles southeast of 

 Pine Island Sound. Juvenile pink shrimp from 

 Indian Key are definitely affiliated with the 

 Tortugas stocks, although almost three times as 

 many marked shrimp released at Indian Key were 

 recovered on the Sanibel grounds as on the Tortu- 

 gas grounds. Analysis of recoveries from release 

 sites 10, 14, and 6 suggests that the northward 

 distribution of Tortugas pink shrimp along the 

 Florida west coast ends north of Indian Key. 



Southward from Indian Key to Shark River (6), 

 Flamingo (2), and the Whitewater Bay-Florida 

 Bay complex, we found the northeasterly penetra- 

 tion of the Tortugas pink shrimp stocks restricted 



by the land mass of the Florida peninsula, not by 

 the coastline. For the Whitewater Bay drainage 

 area, Tabb, Dubrow, and Jones (1962) presented 

 evidence linking juvenile shrimp from estuaries 

 upstream (inland) to the Tortugas population and 

 to coastal release sites proven to be Tortugas 

 affiliated. 



The Tortugas pink shrimp recruitment range 

 extends eastward at least to Bottle Key (9) and 

 probably ends at the periphery of northeastern 

 Florida Bay. Evaluation of the results of releases 

 6, 2, 9, 3, and 7 strongly indicates that all of Florida 

 Bay provides recruits to the Tortugas fishery. 

 Evidence that a separation of stocks may occur 

 between Bottle Key and Barnes Sound (5) is 

 indicated by the fact that considerably more 

 marked shrimp were released in the Tortugas non- 

 contributing areas northeast of Bottle Key than 

 in the adjacent contributing areas to the south- 

 west. A total of 40,217 marked shrimp was re- 

 leased in Biscayne Bay (1, 8, and 11) and Barnes 

 Sound as compared to a total of 15,035 released 

 near Peterson Keys (3) and Bottle Key. Re- 

 coveries in Barnes Sound were particularly 

 interesting, because some marked shrimp were 

 recovered near the release site more than 5)i 

 months after release. The Biscayne Bay and 

 Barnes Sound releases, however, occurred in late 

 spring and summer, while the Peterson Keys and 

 Bottle Key releases occurred in late fall and winter. 

 The possibility cannot be discounted that migra- 

 tion patterns and, therefore, stock distribution 

 may vary seasonally. More definitive results 

 might be obtained from releases in both areas 

 during the same season. However, marked 

 shrimp releases at Bottle Key could not be 

 seasonally timed to coincide with the prior release 

 in Barnes Sound because pink shrimp occur in 

 sparse quantities in northeastern Florida Bay 

 during the summer. 



The negative results of the Lower Matecumbe 

 Key release (4) can possibly be attributed to a 

 separation of stocks in that area, but are more 

 likely a reflection of the relatively few (1,672) 

 marked individuals released. 



In the offshore waters east of the Tortugas 

 grounds, the Tortugas pink shrimp recruitment 

 range extends at least to that part of Hawk 

 Channel (7) south of Bahia Honda Key. How- 

 ever, if shrimp from the Peterson Keys-Bottle 

 Key area are found to use the adjacent Hawk 



456 



U.S. FISH AND WILDLIFE SERVICE 



