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Flight behaviour

Migratory Lepidoptera are, in most cases, excellent flyers. Species like the Vanessa atalanta are capable of managing a fierce headwind. In case of headwind, they usually fly low and are more goal-oriented. During migration, some species can be found on high altitudes, ranging to up to two kilometers This is especially noteworthy for day-flying species like Vanessa atalanta, since the temperatures on these altitudes are low and day-flying species depend on the outside temperature to stay warm. It is thought that Vanessa atalanta produces enough body warmth during flight since it has also been recorded migrating at night.

Most migratory Lepidoptera prefer flying with a favourable wing, as is the case with the migration of Vanessa carduiVanessa carduiThe Painted Lady is a well-known colourful butterfly, sometimes known in North America as the Cosmopolitan. This butterfly has a strange pattern of flying in a sort of screw shape.-Distribution:...
from AfricaAfricaAfrica is the world's second-largest and second most-populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area. With a billion people in 61 territories, it accounts for about 14.8% of the...
to SpainSpainSpain , officially the Kingdom of Spain , is a country located in southwestern Europe on the Iberian Peninsula.The Spanish constitution does not establish any official denomination of the country, even though España , Estado español and Nación española are used interchangeably...
.

That the migratory species are good flyers, is not the same as saying they are robust flyers. The small Diamondback mothDiamondback mothThe Diamondback moth , sometimes called cabbage moth, is a European moth believed to originate in the Mediterranean region that has since spread worldwide. The moth has a short life cycle , highly fecund and capable of migrating long distances....
is also a migratory species that migrates 3,000 kilometers and can be found up to altitudes of 100 meters or more..

Navigation

To be able to migrate over long distances, species must be able to navigate. There are several ways they do this.

Landscape: Lepidoptera use coastal lines, mountainMountainA mountain is a large landform that stretches above the surrounding land in a limited area usually in the form of a peak. A mountain is generally steeper than a hill. The adjective montane is used to describe mountainous areas and things associated with them...
s, but also man-made roads to orient themselves. Above sea it has been observed that the flight direction is much more acurate if the landscape on the coast is still visible.

Celestial navigation: Butterflies are known to be capable of navigation with the help of the sun. They can also navigate by using polarized lightPolarizationPolarization is a property of waves that describes the orientation of their oscillations. This article primarily covers the polarization of electromagnetic waves such as light, although other types of wave also exhibit polarization....
. The polarization of the sun's light changes with the angle of the rays, hence they can also navigate with cloudy weather. There are indications that they can even make corrections depending on the time on a day. Diamondback moths are known to fly in a straight trajectory which is not dependent on the angle of the suns rays. Tests have been performed to interfere with the biological clock of certain species by keeping them in the dark and then observing if they would choose for other flight paths. The conclusion was that some species did, and others did not. Night flyers cannot use sun light for navigation. Most of these species rely on the moon and stars instead.

Earth’s magnetic field: A number of moths use the Earth's magnetic fieldEarth's magnetic fieldEarth's magnetic field is approximately a magnetic dipole, with the magnetic field S pole near the Earth's geographic north pole and the other magnetic field N pole near the Earth's geographic south pole...
to navigate, as a study of the stray Heart and DartHeart and DartThe Heart and Dart is a moth of the family Noctuidae. A familiar moth to many, it is considered one of the most common of the European region....
suggests. Another study, this time of the migratory behaviour of the Silver YSilver YThe Silver Y is a migratory moth of the family Noctuidae which is named for the silvery Y-shaped mark on each of its forewings.-Description:...
, showed that this species, even at high altitutes, can correct its course with changing winds, and prefers flying with favourable winds, which suggests a great sense of direction. Aphrissa statira in PanamaPanamaPanama, officially the Republic of Panama , is the southernmost country of both Central America and, in turn, North America. Situated on the isthmus connecting North and South America, it is bordered by Costa Rica to the northwest, Colombia to the southeast, the Caribbean Sea to the north and the...
loses its navigational capacity when exposed to a magnetic field, suggesting it uses the Earth’s magnetic field.