PREDATORY AND SCAVENGING BEHAVIOR OF MICROVELIA-MACGREGORI (HEMIPTERA, VELIIDAE), A WATER-SURFACE BUG FROM NEW-ZEALAND

Microvelia macgregori (Hemiptera, Gerromorpha, Veliidae), a common wat er-surface insect in New Zealand, often lives in aggregations and feed s communally by predation and scavenging. Prey-location, prey-capture, feeding, and group-member interactions are examined. Experimental inv estigation of prey-location cues indicate that vibratory cues from bot h the struggling prey and from conspecifics are important. Optical cue s are also used, but there is no evidence that chemical cues have a ro le. Findings are considered in relation to other studies on gerromorph ans.