Two experiments examined the responses of red spitting cobras ( Naja mossambica pallida) to stimulus properties of rodent prey. In experiment 1 cobras exhibited elevated rates of tongue flicking (RTF) and trail-following behaviour after striking mice and after 15-s presentations of visual-chemical-thermal cues arising from mice held just out of striking range. Disturbance with a clean snake hook did not produce similar effects. In experiment 2 these cobras were compared with prairie rattlesnakes ( Crotalus v. viridis). All snakes were exposed to five stimulus conditions in their home cages: (1) 3 s of disturbance (D) with a clean snake hook; (2) 15 s of D; (3) 3 s inspection of a live mouse held out of striking range (NS); (4) 15 s of NS; and (5) a presentation of a live mouse inside striking range (S). The snakes always struck in the latter condition, usually within 3 s. Rattlesnakes exhibited elevated RTF only after S, whereas cobras did so after 15 s of both NS and S. The performance of rattlesnakes was consistent with the assumption that these animals are ambushers; that of cobras was consistent with the assumption that these animals are active hunters which will chase and catch visually detected prey.