We studied the polyphagous predators,Typhlodromus pyri (Tp)Schunten andAmblyseius andersoni (Aa)Chant, to test if either had shorter residency times on leaves with abundant prey or had greater tendencies for interleaf movement than the oligophagous mites,Metaseiulus occidentalis (Mo)(Nesbitt) andNeoseiulus fallacis (Nf)(Garman), or if the opposite trends among species occurred when these mites were held without prey. Tests were nm on single apple,Malus pumilaMiller, leaves or apple seedlings. Residencey times for immatures on leaves with no prey were much shorter forM. occidentalis, but with prey they were shorter forT. pyriand much shorter forA. andersoni. Residency times for female adults with no prey were similar among species, but with prey they were longest forM. occidentalisand shortest forA. andersoni. Patterns of interleaf movement of immatures were similar to residency data. On seedlings with abundant prey, larvae of all species moved little, but nymphs ofA. andersoniandN. fallacismoved more than nymphs ofT. pyriandM. occidentalis. Larvae ofM. occidentalisheld without prey moved most but its nymphs died and nymphs ofT. pyriandN. fallacismoved more than nymphs ofA. andersoni. Larvae with moderate levels of prey moved little butT. pyrinymphs moved less far than others. Immature losses were related to movement levels. Overall, data agreed with our hypotheses and helped explain whyM. occidentalisandN. fallacisare better adapted to respond numerically to outbreaks of spider mites whereasA. andersoniandT. pyriare better adapted to keep them at low levels. Movement patterns are discussed in relation to competition and species displacement among these 4 mites.