PHILIPPINE LAKES 



By Wallace E. Pratt 

 {From the Division of Mines, Bureau of Science, Manila, P. I.) 



ONE PLATE AND 2 TEXT FIGURES 

 INTRODUCTION 



An incomplete list of Philippine lakes appeared in 1900,^ and 

 brief notes on different lakes have been recorded in various 

 geographic and geologic studies of the Philippines, but these 

 observations have not been assembled in collected form. The 

 Bureau of Science recently received a request from a European 

 geographic journal, compliance with which necessitated a com- 

 pilation of the existing data with regard to lakes in the Philip- 

 pine Islands. In order that the information brought together 

 for this purpose might be made more widely available locally, 

 it was prepared for publication in this Journal. 



The origin of most of the lakes in the Philippines is closely 

 related to volcanic and seismic activity. A number of smaller 

 lakes occupy the craters of extinct volcanoes; others owe their 

 existence to subsidence and differential vertical movement re- 

 sultant upon volcanic activity or to the obstruction of drainage 

 courses by lava flows and by fragmental volcanic ejecta. In the 

 central valley of Luzon, along Cotabato and Agusan Rivers in 

 Mindanao, and in other low-lying areas in the Archipelago, more 

 or less permanent bodies of water are encountered which prob- 

 ably occupy abandoned portions of the courses of shifting rivers 

 and low areas between the alluvial flood plains of adjacent, 

 parallel streams. 



Among the forty or more lakes which are known in the Philip- 

 pines only three, namely, Laguna de Bay or Lake Bay in Luzon, 

 Lake Bombon or Taal in Luzon, and Lake Lanao in Mindanao, 

 stand out prominently because of their size or economic impor- 

 tance. On the other hand, because of the importance of fish 

 in the diet of the average Filipino, districts in which lakes occur, 

 even in the cases of small lakes in isolated regions, have always 

 been better known to the people than the surrounding inland 

 country. 



'El Archipielago Filipino. Washington (1909), 2, 439. 



223 



