Cool winds and heavy rain brought a massive swarm of butterflies to Lebanon this past month, an exceptional event which has delighted nature lovers. "This is the first time in decades that Lebanon witnesses such a high number of butterflies," Nabil Nemer, Professor of Entomology at the Holy Spirit University of Kaslik, near Beirut, told <em>The National</em>. The vanessa cardui or “painted lady” butterflies – an orange and black variety speckled with white dots – are among the most common species worldwide. The first arrivals were spotted first over a month ago in south Lebanon before the swarm spread to the whole country, causing excitement among nature lovers and city-dwellers alike. “It was beautiful seeing millions of butterflies, like confetti in the sky,” said Yasmina El Amine, a researcher on climate change and the environment at the American University of Beirut. “Everyone on campus enjoyed the beginning of spring with this migration.” Cold winds from eastern Europe and unusually temperate weather for this time of year have encouraged the butterflies to extend their stay in Lebanon as they migrate from Africa to Europe for the summer. An entire generation of butterflies, whose average life-span is 25 days, will be spending the spring in Lebanon. They will then move on to Europe before returning to Africa for the winter, travelling up to 12,000 kilometres in a year. Climate change may be partly responsible for the painted lady’s extended stay in Lebanon this spring. A rain gauge at Kefraya ski resort recorded 1,300 mm of precipitation since January, said Mr Nemer, compared to a season average of 900 mm. “This is a consequence of climate change,” said Mr Nemer. “Rain patterns are disrupted. One year might witness heavy rains, and the next could be dry.” Despite their impressive numbers, their presence will not damage the environment. “Unlike swarms of locusts, the butterflies do not harm agricultural crops,” Mr Nemer said. “They also represent an increase in food material for birds who eat them, and by pollinating more flowers, they will increase biodiversity.” Environmentalists hope the butterflies will continue returning to Lebanon by the millions. Nizar Hani, manager of the Chouf reserve, Lebanon's largest nature preserve, said they reminded him of the butterfly valley in Rhodes, Greece, where huge numbers of butterflies congregate every May, attracted by the scent of a local tree, the oriental sweetgum. “Hopefully, in the future, butterflies in Lebanon can also become an attraction and remind people of the importance of protecting butterflies and insects,” he said.