THE NATURAL FLIGHT OF THE MIGRATORY LOCUST, LOCUSTA-MIGRATORIA L .3. WING-BEAT FREQUENCY, FLIGHT SPEED AND ATTITUDE

High speed cine film of L. migratoria swarms was analyzed. Variables were studied and compared where possible with laboratory data. Wing-beat frequencies of locusts of Australian and New Guinea swarms (mean 22.9 Hz) were higher than laboratory figures (19.8 Hz). Mean flight speed was 4.6 m/s, which was higher than laboratory figures (3.3 m/s). Mean body angle to horizontal was 7.4.degree., and to flight path (in the vertical plane) was 5.2.degree.. Flight speed was correlated with wing-beat frequency with a similar regression line to that found in laboratory work. Ascent angle was positively correlated with body angle to horizontal, but not correlated with body angle to flight path.