Simple rules guide dragonfly migration

摘要: Every year billions of butterflies, dragonflies, moths and other insects migrate across continents, considerable progress has been made in understanding population-level migratory phenomena. However, little is known about destinations strategies individual insects. We attached miniaturized radio transmitters (ca 300 mg) to the thoraxes 14 dragonflies (common green darners, Anax junius) followed them during their autumn migration for up 12 days, using receiver-equipped Cessna airplanes ground teams. Green darners exhibited distinct stopover days. On average, they migrated every 2.9+/-0.3 average net advance was 58+/-11 km 6.1+/-0.9 days (11.9+/-2.8 d-1) a generally southward direction (186+/-52 degrees). They exclusively daytime, when wind speeds were less than 25 h-1, regardless direction, but only after two nights successively lower temperatures (decrease 2.1+/-0.6 degrees C minimum temperature). The patterns apparent decision rules are strikingly similar those proposed songbirds, may represent general strategy long-distance organisms with high self-propelled flight speeds.