290 American Fisheries Society 



by 1,200 feet, with a strong earthen retaining wall and was 

 subdivided as follows : 480 feet from the upper end had 

 been built a low cross-embankment with a sluice gate near 

 one end; 600 feet farther down was a similar wall and gate; 

 the narrow strip at the lower end was subdivided into two 

 unequal ponds, the larger opening into the adjacent large 

 pond and also into the small one, the latter also into the large 

 pond and by an outlet into the neighboring river. The two 

 large ponds serve as the main stock ponds; they may be used 

 in conjunction or separately. The third is used mainly for 

 holding the young fry until they have reached sufficient 

 size to admit of their introduction into the main ponds; the 

 smallest serves as a control and as a place for catching the 

 fish. The water level is controlled by wooden gates fitting 

 into masonry and is normally kept from three to five feet 

 deep. Whenever desired, much of the water is drained oft at 

 low tide and the pond refilled by the incoming tide. Screens 

 of closely woven hemp fibre (sinamay), closely woven bam- 

 boo mats and the like are used to prevent the fish from es- 

 caping. 



The ponds require but little care. If they are in need 

 of cleaning the water is drawn off and natives armed with 

 pieces of boards scrape down the soft mud and force it out 

 with the outgoing current into the river. 



Attempts at artificial propagation of fishes have proved 

 unsuccessful; instead the ponds are stocked each year with 

 young fish taken from the sea. The milkfish, Chanos chanos 

 ( Forskal ), possesses to an exceptional degree the character- 

 istics needed in artificial cultural methods and is practically 

 the only species planted. Many others (mullets, gobies. 

 eels, species of Ambassis, Elops, Megalops, etc., and a 

 shrimp) find their way into the ponds and add to the total 

 output. 



The milkfish is a pelagic form. \i spawns in the shallow 

 water near sandy beaches. From April to August, the 

 young may be caught in the surf near these localities. They 

 are most abundant in May. A strip of coarsely woven 



