The ecological impact of tilapia cage culture in Sampaloc Lake, Philippines

Abstract

Sampaloc lake showed imminent biological death as a consequence of intensive tilapia farming in floating net cages. The progressive disappearance of dissolved oxygen in the entire water column may be an irreversible trend due to continuous feeding. The high amount of BOD₅ and the near toxic concentration of total ammonia and total sulphides are ominous signs. Other ecological changes in the lake are the non-appearance of Microcystis bloom, change in phytoplankton composition, number, and species diversity.