Lake Lanao is the largest lake in Mindanao and the second largest in the Philippines, located in Lanao del Sur in the southern island of Mindanao with a surface area of 340 square kilometers). The lake is home to 18 endemic species of cyprinid fish in the genus Barbodes (most were formerly in Puntius) Ismail et al, 2014. 

Mollusks and crustaceans are invertebrates which have a big role in the ecosystem, they are important in the food chain, they serve as a food, medicine and source of income. However some mollusks like the gastropod species are necessary important hosts for parasitic flatworms such as the species that cause schistosomiasis in human.  To date, they have caused millions of dollars in commercial damage by clogging the water pipes of power plants and cooling systems. They are driving many native freshwater bivalve species to extinction (Salvini-Plawen, 2014). Mollusks provide a sensitive tool for monitoring environmental health. They are sensitive to changes in their environment and therefore could provide an early warning of habitat deterioration (Wells, S.M., and J.E. Chatfiled (1992). Direct habitat destruction by human activities, such as forest clearing, dam construction, pollution and introduction of non-native or exotic species, intention or not are the two main reasons of declining the native mollusks (Parent, 2018).  

The same with mollusks, crustaceans are of great direct and indirect importance to human beings. Literature showed that there were 42 crabs in the lake identified before. But these days, elders observed that there were much lesser crabs and shrimps available in the local markets of Lanao del Sur than before. Crustaceans also play many roles in aquatic ecosystem. The planktonic forms, such as the copepod and the krill, feed on the microscopic plants floating in the water and in turn eaten by the fishes. The crabs for example are also important predators. So, depletion or an increase of any of the crustacean species in the lake can disrupt its ecosystem. 

Among plant species, the very famous water hyacinth (Eichhorniacrassipes) is also introduced and became invasive aquatic plant (Joshi 2011) and its massive growths are evident not just in the Lake Lanao but in any freshwater habitats here in Mindanao. Water hyacinth, being labeled as the “ecosystem engineer” or “invasive habitat modifier” recently alarms the government since it clogs waterways causing destructing floods in Cotabato in 2011; it makes boat transport and fishing activities difficult, and obviously affecting fisheries productivity (MacKinnon, 2002).

 The main purpose of this study is to assess the indigenous, endemic mollusks and crustaceans; investigate the presence of introduced exotic (invasive) species in Lake Lanao and to evaluate their abundance, productivity and distribution. Importantly the study will try to assess the impacts of the introduce species (crustaceans and mollusks) in Lake ecosystem. 

The targeted mollusks to be studies are gastropods, bivalves and other classes of mollusks such as cephalopods. Though cephalopods are mainly found in the marine ecosystem, the researcher will find any of its presence in the lake. The targeted crustaceans to be studied are shrimps, crabs and others crustaceans that can be seen in Lake Lanao.

The study hopes to furnish basic information regarding introduced species in the lake and to provide basis for policy formulation and appropriate actions to be implemented in order to protect the endemic/indigenous species of Lake Lanao.