Chasing the High Fliers: Recent Advances in the Study of Insect Migration
Dr Jason Chapman, Insect Migration & Spatial Ecology group, Rothamsted Research, UK
Monday 17 June 2013, 1600-1700
Lecture Theatre 10, Management School Building
Billions of insects migrate between winter and summer ranges to take advantage of seasonally-available breeding resources. To cover the distances required (100s km), many insects rely on wind assistance, and routinely ascend 100s m above the ground to migrate in fast-moving airstreams. Given that wind speeds are typically three to five times faster than the insects' airspeeds, it was not clear what influence high-flying migrants could exert on their migration direction or whether substantial 'return' migrations to lower-latitude winter-breeding areas were possible. To answer these questions, Dr Chapman has studied the flight behavior and migration patterns of the Silver Y moth (Autographa gamma) and the Painted Lady butterfly (Vanessa cardui) with specialized entomological radars. Radar observations demonstrate that an ability to select favorable fast-moving airstreams is widespread among high-flying migrant Lepidoptera, and thus migrants gain considerable wind assistance for their seasonal migrations. Comparison of moth migration parameters with those of nocturnal songbirds demonstrates that the moths' highly efficient strategies result in them achieving the same travel speeds and directions as birds capable of flying three times faster.
Chapman JW et al (2012). Seasonal migration to high latitudes results in major reproductive benefits in an insect. PNAS 109: 14924-14929.
Alerstam T & Chapman JW et al (2011). Convergent patterns of long-distance nocturnal migration in noctuid moths and passerine birds. Proceedings of the Royal Society B 278: 3074-3080.
Chapman JW, Nesbit RL, Burgin LE, Reynolds DR, Smith AD, Middleton DR and Hill JK (2010). Flight orientation behaviours promote optimal migration trajectories in high-flying insects. Science 327: 682-685.