Butterflies are a bit like migratory birds – and retirees. They are in the north in the summer, and migrate to warmer regions in the winter. But in recent years, researchers and those who observe the butterflies have seen that there have been both more individuals and more species. – The butterflies have always migrated north every year, but it is especially in recent years that they have become more numerous, says Stig Lundmo. He has observed butterflies in Rana municipality in Nordland for many years and works as a preparer, one who “stops out” butterflies for Rana Museum’s butterfly exhibition. A spring blue wing is among the country’s new species that have migrated all the way up to Nordland. Photo: Stig Lundmo There are two types of butterflies in particular that have increased in the north in recent years: Admiral and thistle butterfly. Admiral is a well-known creature that many people probably know. The butterfly first lays eggs on stinging nettles on the Mediterranean coast and in the Middle East. Then the new butterflies fly north, and can get all the way from the Mediterranean to Norway in one week. This is an admiral butterfly. The first discovery was in 1980. After that, many years passed until the next discovery. In the last 10-15 years, they have become a common sight. It weighs less than a feather. A narrow-edged hop swarm is one of the country’s new butterfly additions. It looks like a hop, but the behavior is quite different. This beautiful creature is a spring bluebird. Spring bluewing is found in Denmark, and southeastern Sweden and Finland. In southern Norway along the coast to Rogaland. Has been found with a few finds in Central Norway, and now in Nordland. Gamma fly is a night butterfly that migrates north. White C is a new butterfly species in Nordland. Can spend several generations on the journey Since the Admiral Butterflies only live for a few weeks, some generations spend on getting to their northern destination. – They can spend both generations or a couple of weeks on the journey. There is a question about the winds, Leif Aarvik explains. He is an entomologist at the Natural History Museum in Oslo and has been researching butterflies since the 70s. – Some settle down between Europe, lay eggs, and then it is the new generation that flies further north. Some facts about butterflies Photo: Stig Lundmo Most butterflies are moths and moths. We have over 2000 night butterfly species, but only 100 day butterflies. The Admiral butterfly flies at a speed of approx. 14 km / h. They can fly from the Mediterranean to Norway in a week with the right winds. So far, 734 species are known in Nordland alone. This is about one third of Norway’s entire butterfly population. In the last 30 years, 150-200 new butterfly species have come to Norway. 20-30 of these are permanent residents in the north, such as the spring bluewing. The rest are visiting and flying back to warmer countries in the winter, just like the migratory birds. Source: Stig Lundmo at Rana Museum and Leif Aarvik at the Natural History Museum in Oslo. And if the wind from the south is strong, they can handle it in one life. – When there have been periods of strong southerly winds, we see many admirals in Norway. Then they hatch here in the summer. Admirals do not usually overwinter, but Stig Lundmo in Rana says he observes more who manage to overwinter, also further north than before. Nevertheless, most fly back to the “South” when autumn comes. Warmer climate sends them north The climate is emerging as the main reason for insects migrating north. The theory is supported by Aarvik and Lundmo, among others. Among others, Science Daily writes that both animals, insects and plants move north as it gets warmer in the south, but at the same time milder in the north. – We get new butterfly species every year. Sometimes a new species is established in one place, but then it disappears again due to a wet and cold summer. But then they can come back, re-establish themselves, survive, and settle down, Aarvik explains. Ecosystems are not affected Neither Lundmo nor Aarvik believe more and new butterfly species are messing up the ecosystem that already exists among the insects. – The butterflies establish themselves on, for example, a local tree species that belongs here. They become a natural part of the fauna. There is a bigger problem with plants that displace their own species. He has found no evidence that butterflies displace other butterflies. – We have butterflies on the red list, but that is because their natural habitat disappears. The species database shows a marked increase in the number of butterflies since 1808. On the website artsobservasjoner.no, anyone can enter their findings.
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Warmer climate gives more butterflies – news Nordland
