THE COMMERCIAL SPONGES AND THE SPONGE FISHERIES. 495 
fishery are such that it is difficult to obtain statistics which will show the actual 
product of the beds in those waters. 
On the African coast the yield of the beds during the past fifteen or twenty 
years has been fairly maintained, though most writers on the subject have 
expressed the opinion that the productiveness of the beds is waning, and that 
the average size of the sponges is growing smaller. Such statistics as I have 
been able to obtain show a rather remarkable uniformity in the total catch. In 
the fishery tributary to the Benghazi market the only material variation in.the 
catch between 1889 and 1895 can be traced to a difference in the intensity of 
the fishery, especially in the number of scaphanders employed. In Tunis during 
the twenty years between 1885 and 1904 the maximum yield has exceeded the 
minimum by about 25 per cent, and the catch of 1904 was greater than for 
any year previously recorded, excepting 1890 and 1894. ‘The average catch of 
three years prior to 1892 was 216,000 pounds and for five years since that date 
224,000 pounds. In this connection it must be noted, however, that between 1890 
and 1892, principally in the latter year, there was a rapid increase in the number of 
fishermen from about 3,000 to about 4,500 with a corresponding increase in the 
number of boats employed. In other words, if the statistics be reliable, an 
increase of 4 per cent in the average yield of the fishery has been produced by 
an increase of about 50 per cent in the number of fishermen. This, possibly, 
may be accounted for to some extent by changes in regulations or methods of 
which I am ignorant, but the facts substantiate the statement that the dealers 
of Sfax and the spongers themselves are of the opinion that the fishery is being 
depleted, as indicated by the smaller catch per man employed and the increasing 
proportion of small sponges. 
The total product of the banks of Lampedusa has decreased materially 
since 1888-1899, when the fishery reached a maximum in both yield and inten- 
sity. Considered by five-year periods, the available statistics appear to indicate . 
some depletion of the beds during recent years. During five years from 1890 
to 1894, inclusive, the average catch per sponger was about 151 pounds, the 
average of five years from 1895 to 1899, inclusive, was the same, while the average 
of the four years from 1go1 to 1904, inclusive, was but 120 pounds, a decrease 
of 20 percent. Owing to the fluctuating proportions of seaphanders and dredges 
from year to year and other variations in the fishery, it may be that this decrease 
has no great significance, but those familiar with the beds are of the opinion 
that their productiveness has decreased. It is noteworthy also that the smallest 
catches made since 1889 were in the years immediately following the intense 
fisheries between 1895 and 1900, when the largest number of men and boats 
were employed and the beds most thoroughly scoured. In the Mediterranean 
the dredge and the scaphander are both blamed for the depletion of the beds, 
the former because it tears everything from the bottom and the latter because 
