FISHERY RESOURCES OF THE PHILIPPINE ISLANDS. Ul 



very abundant. Such a bank was found just south of Basilan Island; 

 another near the Tapu Islands, and another in Tataan I'ass of Tawi-Tiiwi 

 Island. A large j'ield of shell has been sccui^mI neai' the Saniales group. 

 Shell has been re})or(e(l from Illana Bay, and during the past year an 

 extremely valuable bank was located in the (iulf of I)a\ao in Pakipiitau 

 Strait between Sanial Island and the mainland. The most prolific por- 

 tion of the bank was in the narrow part of the passage directly between 

 Point Lanatig and Point Linao. The depth of water is from 20 to '3-") 

 fathoms. The bank is well protected above by the large reef known as 

 Arboles Island. Usually, there is a very strong current pouring through 

 this strait, but at the point where the pearl bank occurs the tides and 

 curi'ents form a strong eddy which has doubtless contributed to the 

 formation of the liank by giving an opportunity for the spat to settle and 

 attach. The bottom is of coral, sand, and gravel, and is comparatively 

 smooth. The width of the sirait at this place is less than 1.6 kilometer 

 (1 luile) ; the Ijeach on one side slopes steeply dow^n, and on the other 

 drops abruptly into several fathoms of water from a live coral reef. The 

 water is quite clear, its temperature about 21° ('., and its specific gravity 

 1.0-?2. At the time of my visit (May, 1908), there were only four 

 pearling boats operating on this bank; two others were priisjiectiug in 

 adjacent wateis. 



The currents wcic so swift that diving could be carrieil on only between 

 the hours of 6 and ", o'clock in the morning. The diver, a Filipino, 

 during this hour made three trips to the bottom; on the first lie secured 

 three shells; on the second, eight; and on the third, two. These were 

 all large, first-class shells, each weighing about 3.2 kilos (1 pounds). 

 One contained a small pearl. 



The diver hi ought up some young -liells for our inspection, and reported 

 that they were abundant on the lied. All the large oysters were in a 

 breeding condition, so probably this bank will be able to keep up a 

 moderate yield, unless overfished at the beginning. So far, the Davao 

 pearl bank has yielded about 56 tons of first-class shell. 



I'carl shells in considerable numbeis are found in Tanon Stiail, between 

 C'cbu and Xegros Islands; in the vicinity of Guimaras; and also along 

 the west and the north coast of Samar. Shell has also been reported 

 from Palawan and Cagayan Sulu. It is more probable that as the 

 Islands become better known, many new pearling banks will be found, 

 and those now known will lie mapped and better defined. 



The most desirable bottom for a pearl bank is coarse sand, with dead 

 coral and rock to which the young may attach. Tlie\- can not grow on 

 live coral, and they are very apt to be covered up and smothered on fine 

 sand. 



