Seasonally adaptive migratory headings mediated by a sun compass in the painted lady butterfly, Vanessa cardui

TY - JOUR

T1 - Seasonally adaptive migratory headings mediated by a sun compass in the painted lady butterfly, Vanessa cardui

AU - Nesbit, R. L.

AU - Hill, J. K.

AU - Woiwod, I. P.

AU - Sivell, D.

AU - Bensusan, K. J.

AU - Chapman, J. W.

PY - 2009/11

Y1 - 2009/11

N2 - Many insects undertake long-distance migrations to exploit seasonally variable conditions at high latitudes, but the mechanisms used by migrants to select and maintain beneficial flight headings are poorly understood. Using computerized flight simulators, we performed controlled experiments to test the ability of an obligate migrant butterfly (Vanessa cardui) to orient in seasonally advantageous directions (i.e. northwards in spring and southwards in autumn). We also investigated the compass mechanism used to select and maintain these headings. Laboratory-reared autumn-generation butter. flies flown in the U. K. displayed a highly significant mean orientation towards the south-southwest, consistent with return migration to winter breeding sites. However, seasonally adaptive flight headings were not observed in wild-caught adults. own at the same time. Spring-generation adults caught in Gibraltar (presumed to be migrating from winter breeding sites in North Africa into Europe) showed no evidence of northward flight headings, but produced a wide scatter of flight headings with a mean direction towards the west. Butterflies. own in the simulators when the sky was not visible produced a random scatter of flight headings and less-directed flight tracks, providing evidence that migrating V. cardui use a sun compass to select and maintain their flight headings. However, when butterflies were subjected to a 6 h clock shift, no change in orientation was observed relative to the control group. Field evidence for a return migration in autumn by V. cardui is surprisingly scarce in the literature, but we conclude that the species does attempt such southward movements and that individuals use a sun compass to select their migratory heading. (C) 2009 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.

AB - Many insects undertake long-distance migrations to exploit seasonally variable conditions at high latitudes, but the mechanisms used by migrants to select and maintain beneficial flight headings are poorly understood. Using computerized flight simulators, we performed controlled experiments to test the ability of an obligate migrant butterfly (Vanessa cardui) to orient in seasonally advantageous directions (i.e. northwards in spring and southwards in autumn). We also investigated the compass mechanism used to select and maintain these headings. Laboratory-reared autumn-generation butter. flies flown in the U. K. displayed a highly significant mean orientation towards the south-southwest, consistent with return migration to winter breeding sites. However, seasonally adaptive flight headings were not observed in wild-caught adults. own at the same time. Spring-generation adults caught in Gibraltar (presumed to be migrating from winter breeding sites in North Africa into Europe) showed no evidence of northward flight headings, but produced a wide scatter of flight headings with a mean direction towards the west. Butterflies. own in the simulators when the sky was not visible produced a random scatter of flight headings and less-directed flight tracks, providing evidence that migrating V. cardui use a sun compass to select and maintain their flight headings. However, when butterflies were subjected to a 6 h clock shift, no change in orientation was observed relative to the control group. Field evidence for a return migration in autumn by V. cardui is surprisingly scarce in the literature, but we conclude that the species does attempt such southward movements and that individuals use a sun compass to select their migratory heading. (C) 2009 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.

KW - butterfly

KW - flight simulator

KW - migration

KW - orientation

KW - painted lady

KW - Vanessa cardui

KW - POLARIZED SKYLIGHT

KW - DRIFT COMPENSATION

KW - PIERIS-BRASSICAE

KW - BOUNDARY-LAYER

KW - LEPIDOPTERA

KW - ORIENTATION

KW - ATALANTA

KW - MOTH

KW - MIGRANT

KW - NYMPHALIDAE

UR - http://www.scopus.com/inward/record.url?scp=70350077291&partnerID=8YFLogxK

U2 - 10.1016/j.anbehav.2009.07.039

DO - 10.1016/j.anbehav.2009.07.039

M3 - Article

SN - 0003-3472

VL - 78

SP - 1119

EP - 1125

JO - ANIMAL BEHAVIOUR

JF - ANIMAL BEHAVIOUR

IS - 5

ER -