The study would determine the present population status of the introduced species (Hypseleotris agilis and Glossogobius giurus) believed to have proliferated to such an extent that they affect the population of the endemic species, as wells as the remaining endemic species (only two, Puntius tumba and P. lindog are believed to be extant). Morphological characterization of these species would also be accomplished. The study would also do spawning and fecundity measurements. 

Present studies have shown populations of endemic species in Lake Lanao are declining (Escudero, 1984). Ismael (2011) in her survey of endemic species listed only two: Puntius tumba and P. lindog, of the 18 endemic described listed by Herre in 1924. Both these fishes are listed as endangered (Fishbase, 2004). 

These surveys were focused on the fish catch by fishermen which usually go fishing in established fishing areas within the Lake itself. The collection/sampling sites in this present study would focus on the streams and rivers that drain into the Lake, using fish traps and fishing nets. Fish landing surveys will also be accomplished in several fish landing zones to gather the total weight of each kind of fish landed.