migration in this direction. Tabb 

 et al. (1962) report that most post 

 larval shrimp arriving in Coot Bay 

 have 6 to 7 dorsal rostral spines, a 

 characteristic which is believed to 

 indicate distance traveled from 

 spawning grounds. This corresponds 

 to an estimated age of about 35 

 days. Numbers of benthic juveniles 

 within Florida Bay are strongly cor- 

 related with numbers of post larvae 

 incoming through Keys channels 

 (Allen et al. 1980). On the aver- 

 age, juvenile shrimp spend anywhere 

 from 2 to 7 months within the nur- 

 sery area (Costello and Allen 1960). 

 Predation accounts for the majority 

 of losses in both juvenile and 

 larval/post larval stages (Tabb et 

 al. 1962). Roessler et al. (1969) 

 estimate that only 0.05 to 0.14 

 percent of the original protozoea 

 actually reach the Everglades nur- 

 sery grounds as post larvae. 



The exodus of shrimp from the 

 nursery areas appears to be fairly 

 constant all year round (Iversen and 

 Idyll 1960). Older shrimp tend to 

 move into more stable high salinity 

 environments. Yokel et al. (1969) 

 report a high positive correlation 

 between juveniles exiting from Ever- 

 glades National Park waters and 

 recruitment of young shrimp onto the 

 Tortugas grounds. Release and re- 

 covery of tagged shrimp (Costello 

 and Allen 1960) confirms the move- 

 ment of juveniles from Flamingo to 

 the Tortugas grounds and from the 

 lower Keys to the Keys shallows 

 south of the Tortugas grounds. Of 

 the very small percentage of post 

 larvae entering the Everglades nur- 

 sery, Roessler et al. (1969) esti- 

 mate that only about 6% contribute 

 to the following year's commercial 

 catch on the Tortugas grounds. 



In 1972 the spiny lobster ( Pan - 

 ulirus arqus ) ranked as the second 

 most valuable commercial species of 

 shellfish harvested from Florida 



waters (Seaman and Aska 1974). 

 Historically, market demands for 

 lobster have grown steadily while 

 the catch, though clearly rising as 

 well, fluctuates considerably from 

 year to year. However, the increase 

 in catch appears unable to keep pace 

 with the increasing demand. In 1972 

 and 1973, 9.8 and 8 million kilo- 

 grams (21.5 and 17.7 million pounds) 

 respectively of lobster tails were 

 imported into the U.S. compared to 

 3 million kilograms (6.3 million 

 pounds) harvested from Florida 

 waters (Johnson 1974). The vast 

 majority of the state's catch is 

 landed from waters surrounding the 

 Florida Keys. 



There is a growing belief that 

 the Florida lobster fishery is fast 

 approaching the limits of its maxi- 

 mum sustainable yield. Increasing 

 numbers of commercial and sport 

 fishermen, the illegal taking of 

 small and/or gravid females, and the 

 particular population dynamics of 

 the Florida lobster combine to make 

 this a subject of concern to fish- 

 ermen, tourists, and researchers 

 alike. Presently, the taking of 



lobsters is restricted to the period 

 August 1 through March 31. The 

 warmer months, April through July, 

 are considered prime lobster spawn- 

 ing season and are thus closed to 

 fishermen. Legal size allowed is a 

 76.2 mm (3 in) carapace or a 139 mm 

 (5.5 in.) tail (disconnected). The 

 taking of egg bearing female lob- 

 sters, or the stripping of eggs from 

 berried females is strictly prohibi- 

 ted at all times. 



It is generally held that the 

 Florida spiny lobster population 

 depends upon recruitment from Carri- 

 bean stocks (Sims and Ingle 1966). 

 Larvae are believed to be carried by 

 the prevailing currents (Gulf Stream 

 and Florida Current) north to suit- 

 able habitats along the southern 

 Florida coast. Indirect evidence 



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