certainty how long the larva lives after 

 being released. It may be presumed that 

 during part of the life span the larva 

 floats at or near the surface as other 

 larvae do, then towards the end of its 

 life span it sinks to the bottom for at- 

 tachment. Underwater observation of 

 noncommercial sponges closely related 

 to the commercial sponges suggests that 

 larvae are released at various stages 

 after maturation, depending on how deeply 

 they are buried in the matrix of the 

 sponge. A number of these larvae may be 

 released so late in their short life span 

 that they immediately sink to the bottom 

 and attach. What percentage, if any, follow 

 this pattern of behavior would be im- 

 portant to a better understanding of how 

 sponge concentrations are increased. 



3. The effect of various concentrations of 

 sponges on rate of reproduction per 

 sponge needs to be studied in more de- 

 tail. 



4. All five stations established for the study 

 of growth have been left intact. I recom- 

 mend that the necessary arrangements be 

 made to have the spongers not disturb 

 these areas and that they be marked so 

 that the sponges could be remeasured for 

 information on their growth rate. 



5. Much more needs to be known about suit- 

 able habitats for sponges. Reports from 

 the Key West spongers state that some 

 wool sponges grow beneath the limey 

 mud or are at least covered with mud. 

 Certainly a number of wool sponges will 

 continue to grow even though half buried 

 in limey mud or even fine sand. 



The industry is at a critical turning point. 

 There is considerable pressure to expand the 

 sponging fleet, yet the present catch of the 

 best and most efficient diving crew is less 

 than two-thirds the lowest level of take per 

 unit of effort in the 1917-36 period. Increased 

 fishing without a 6-inch size limit will only 

 impede recovery, which at the present time 

 is progressing as fast as one could hope to 

 expect of any biological process. 



The adoption of a 6-inch size limit will not 

 solve all the problems besetting the industry by 

 any means but it is the first step in assuring 

 that no area will be overfished and that concen- 

 trations of sponges will become greater even 

 with increased fishing effort. 



It can be only through the close cooperation 

 between the sponge fishermen, the Tarpon 

 Springs Sponge Exchange, the sponge packers 

 of Tarpon Springs, the large sponge dealers in 

 the north, and the Conservation Department 

 of the State of Florida that a 6-inch size limit 

 could be set and maintained. Unfortunately, 

 everyone concerned must be convinced of the 

 necessity and value of a 6- inch limit before 

 adoption of this law is possible. 



ACKNOWLEDGMENTS 



A considerable amount of help and encour- 

 agement has been received throughout this 

 investigation of the commercial sponges. In 

 particular, mention should be made of Robert 

 Work, who was the assistant during the first 

 year of the investigation. M. Gianaris assisted 

 on two of the field trips. John Maillis of the 

 sponging boat Elini did an excellent job during 

 the deep-water field trip in the summer of 

 1956 and was responsible for collecting sponges 

 for larval examination during the 1956-57 

 period. A number of other diving boats also 

 collected sponge material during the first year 

 of the investigation. L. Smitzes, President of 

 the Tarpon Springs Sponge Exchange, and M. 

 Dritsos, Secretary of the Sponge Improvement 

 Committee, were both most helpful throughout. 

 R. M. Ingle and other personnel of the Florida 

 State Board of Conservation were generous 

 with both advice and assistance whenever the 

 need arose. 



Bud Taylor of Steinhatchee, whose boat. 

 Rose Bros. II, was used for all the ecological 

 studies in the field in the northern Gulf, sup- 

 plied a keen interest, unstinting help, and 

 encouragement in carrying out this phase of the 

 work. Many members of the University of 

 Miami Marine Laboratory (and my wife) as- 

 sisted in discussing the various aspects of the 

 problem, critical reading of the report, and 

 identification of collected material. 



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