126 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



used, which, while slowly acted upon b}- salt water, lasted a sufficient 

 length of time to permit the sponge to permanently heal. 



During the winter months the growth of the cuttings was rather 

 slow, so far as increase in l)ulk was concerned, although eyes, or oscula, 

 were promptly put out and the circulator}' s} stem quickly reorganized 

 and completed. During the spring when the water, especially in the 

 more southern part of the State, was })ecoming warmer, there were 

 indications of more rapid growth. About six thousand cuttings were 

 planted in Biscayne Bay, Sugar Loaf Key, and in the vicinit^^ of 

 Anclote Keys, and in the latter part of April, after they had })een 

 planted for periods varying from two to five months, most of them 

 were growing and in an apparentl}" healthy condition. 



Between the lower end of Biscayne Bay and Matecumbe Kc}' there 

 is a long stretch of water where sponges do not grow naturally. An 

 investigation of this region was made to determine the reason for 

 their absence, and an experimental plant of about a thousand cuttings 

 w'as made in a small sound ])ack of Key Largo, with a view to deter- 

 mining whether they could be artilicially introduced there. At the 

 end of six weeks practically all of thes^e cuttings wen* dead, although 

 others planted at about the same time in more favorable localities 

 were alive and growing. A series of observations developed the fact 

 that the water in this region is of a nuich lower salinity than in places 

 where the sponge grows natural^, and it is probal)le that this is the 

 cause of their absence naturall}^ and of the mortality of the cuttings. 



Practically nothing is known of the rate of growth of sponges under 

 natural conditions, or of the rapidity with which they will develop 

 from fragments and cuttings, and it will probably require several years' 

 investigation to determine these points and to jdevelop, if it can be 

 developed, a system of sponge-culture wdiich will l)e of value to the 

 State of Florida. At the present time the i)i-odiiction of sponges in 

 this State, which is the only one in the country producing them, is 

 about $500,000 per annum. An equal or perhaps greater value of 

 sponges is imported from abroad, and it is hopinl eventually to supply 

 this excess of demand over production by sponges raised artificially. 

 Many of the sponge-dealers arc showing consideral^le interest in the 

 experiments, and it is believed that they will promptly undertake 

 sponge-culture if a reasonably practical method can be developed. 



SURVEY OF THE FLORIDA SPONGE-GROUNDS. 



The steamer Fiah Hawk, working under the direction of this divi- 

 sion, in October, 1001, resumed the survc}- of the sponge-grounds of 

 the western coast of Florida, and in ^March, 1902, completed the exam- 

 ination of the waters lying north of Tampa Bay, comprising all those 

 grounds designated under the names "'(iulf," "Bay," "Rock Island," 

 and "Anclote.'' The location of the sponge-grounds has been plotted 



