Tests were carried out on Mavpan and Malayan Dwarf coconut varieties in two ecological zones, lo assess the yield loss of copra due lo the mite. Eriophves guerreronis Keifer (Acarina: Eriophyidae). The results show a significant decline in copra output with increased mite damage (p<0.001). Total copra losses ranged from 4-5% but may be higher than 80% in the most severely damaged fruit.