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Many populations of Lepidoptera (butterflies or moths) migrate, sometimes long distances, to and from areas which are only suitable for part of the year. Lepidopterans migrate on all continents except Antarctica, including from or within subtropical and tropical areas. By migrating, these species can avoid unfavorable circumstances, including weather, food shortage, or over-population. In some lepidopteran species, all individuals migrate; in others, only some migrate. The best-known Lepidopteran migration is that of the eastern population of the Monarch butterfly which migrates from southern Canada to wintering sites in central Mexico. In late winter/early spring, the adult monarchs leave the Transvolcanic mountain range in Mexico for a more northern climate. Mating occurs and the females begin seeking out milkweed to lay their eggs, usually first in northern Mexico and southern Texas. The caterpillars hatch and develop into adults that move north, where more offspring can go as far as Central Canada until next migratory cycle. The Danaids in South India are prominent migrants, between Eastern Ghats and Western Ghats. Three species will be involved in this, namely ''Tirumala septentrionis'', ''Euploea core'', and ''Euploea sylvester''. Sometimes they are joined by Lemon Pansy (''Junonia lemonias''), Common Emigrant (''Catopsilia pomona''), Tawny coster (''Acraea terpsicore'') and Blue Tiger (''Tirumala limniace''). == Definition == Migration in Lepidoptera means a regular, predictable movement of a population from one place to another, determined by the seasons.〔Scoble, MJ. (1995) "Migration" in ''The Lepidoptera: form, function and diversity''. 68-71. Previewed in Google Books () on 09 Oct 2009.〕 There is no unambiguous definition of ''migratory butterfly'' or ''migratory moth'', and this also applies to proposals to divide them into classes.〔Meerman, J.C. (1987) "(Dutch Sphingidae )" ''Wet. meded. KNNV'' 180.〕 Migration means different things to behavioral scientists and ecologists. The former emphasize the act of moving whereas the latter discriminate between whether the movement has been ecologically significant or not. Migration may be viewed as "a behavioural process with ecological consequences".〔 Migration in Lepidoptera takes place in two of the three modes of migration identified by Johnson (Johnson, 1969). In the first mode (also Johnson's first), the Lepidoptera move in one direction in their short life-span and do not return. An example is the pierid butterfly, ''Ascia monuste'', which breeds in Florida but sometimes migrates along the coast up to 160 kilometers to breed in more suitable areas.〔 In the second mode (Johnson's third), migration takes place to a place of hibernation or aestivation where they undergo diapause and the same generation survives to return. The classic example is that of the nymphalid Monarch butterfly (''Danuas plexippus'').〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Lepidoptera migration」の詳細全文を読む スポンサード リンク
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