FISHERIES OF THE COASTAL WATERS OF FLORIDA. 7 



sponge is brought up on the hook, a crab is found occupying a cavity 

 in the base of the sponge, and it is generally believed that the crus- 

 tacean has eaten the sponge tissue away, thus forming the cavity which 

 it may afterwards occupy; others think that the crab finds the cavity 

 already existing and simply uses it as a place of retreat, and this would 

 seem to be the more reasonable view. 



The greatest injury to the sponges, according to the spongers, is that 

 caused by the so-called "black water" or "poison water." Just what 

 this is does not seem to be definitely known, although knowledge of 

 the occurrence of the phenomenon dates back many years. The more 

 prevalent opinion is that heavy rains cause a strong flow of fresh 

 water from off the land into the sea, and this water, being heavily 

 impregnated with decaying vegetable matter and spreading out over 

 the sponge-grounds, poisons the sea water and kills the sponges. It is 

 claimed that the poison water always follows immediately after unusu- 

 ally heavy and continued rains. Au objection urged against this belief 

 is that this water, being fresh, merely spreads out over the surface and 

 does not reach the sponges except in very shallow water. Those who 

 hold this view maintain that the failure of the sponging vessels to 

 bring in good fares at the time of the prevalence of the black water is 

 not because tlie sponges have been killed, but because the spongers are 

 unable to see them through the colored water. Attempts have even 

 beenmade to devise a water glass which would enable the sponger to 

 see the sponges below the black water. Some are inclined to the 

 belief that the poison water comes not from the land, but rather from 

 subterranean eruptions. It is claimed that sponges have been really 

 killed in this way only once in the last twenty-five years. 



A peculiar malady among the sponges between Knight Key and 

 Cape Sable occurred in 1895. It is said that the sponges appeared all 

 right until brought to the surface of the water, when the whole inside 

 would drop out, leaving nothing but a mere shell. What could have 

 caused the decay of the inside no one has yet been able to explain. 

 According to one witness, these sponges were hollowed out when 

 brought up, and usually a crab was found occupying the cavity. 



Whatever the black water may be and whatever may be its effect, it 

 is certain that the sheepswool sponge is decreasing in numbers very 

 rapidly. All are agreed upon this point, and the cause of the decrease 

 is not difficult to understand. While 500 bunches are now considered 

 a good cargo, a few years ago 1,000 to 1,500 or even 1,800 bunches were 

 often brought in at a single trip. The decrease continues from year 

 to year, the bulk of the fishing is done in deeper and deeper water, 

 and the sponges are harder to get each succeeding year. Grounds 

 which are fished out one year are visited and raked over again the next 

 year, without giving them sufficient time to recuperate. 



The present law of the State of Florida governing the matter makes 

 it unlawful to take any sponge under 1 inches in diameter. It is 



