In this episode, we talk with Mr. Michael Jeriel Bersaldo, a marine biology instructor at SPAMAST, about his study on the fishery status of imbao, the mangrove clam that's one of the most sought-after shellfish in Davao region. A 2010 assessment had found the fishery over-exploited, leading to a policy regulating the size of clams that gleaners are allowed to harvest. Using transect and quadrat sampling designed with the help of local gleaners across Davao Oriental, Davao Occidental, and Davao del Sur, the study re-assessed the fishery status and found imbao still abundant enough for gleaners to sustain their livelihood in all three areas. But in Davao del Sur, the clams being caught averaged just 3.2 cm which is smaller than those in Davao Oriental (4.0 cm) and Davao Occidental (4.2 cm). The small size in Davao del Sur points to overharvesting and if left unchecked, harvesting immature clams could drive a severe local decline.
Research highlight: Bersaldo MJI, Llameg MB, Avenido PM. 2021. Mangrove clam (Pegophysema philippiana) fishery status in Davao region. Davao Res J. 12(5):6-9.