Sum Phearun joined BirdLife Cambodia Program in June 2010 as Ibis Research & Conservation Project Assistant for BirdLife and PRCF-CEPF Ibis project officer based in Lomphat. He is working to serve the purpose of conserving the Giant and White shouldered Ibises in Lomphat Wildlife Sanctuary, Ratanakiri province.

With a BSC in Agriculture, majoiring in Natural Resource Management from Maharishi Vedic University, Phearun used to work as Project Assistant fpr CRDT Organization and volunteered for Association of Farmer Development (AFD) organization, and Center d’Etule et de Development Agricole Cambodgien (CEDAC). He is also working part-time as a Computer Teacher at the university.