Tiny Blue Migratory Butterfly Establishes Itself in Israel
The blue pansy, a small tropical butterfly, has become an increasingly familiar migrant in Israel in recent years. Though it is striking in appearance, the species is notable mainly for its long-distance migration, which brings it across deserts and into temporary colonies in southern Israel and around the Sea of Galilee. Dov Benyamini, chairman of the Israel Butterflies Association and author of butterfly guidebooks, says the insect offers insight into migration, survival and climate change.
Benyamini said the blue pansy is common in tropical and subtropical regions of Africa, Asia and Australia, but reaches Israel only through migration. In the past, it formed temporary colonies in Arad and later at Nahal Zin, while today there is a relatively stable population near Ein Gev, by the Sea of Galilee. He noted that the butterfly settles where its host plant, mainly trailing lantana, grows.
What fascinates him most is the route it takes. He said the butterfly does not arrive from Africa, as is often assumed, but moves north along the western coast of Saudi Arabia. From Eilat, it continues on two paths, one following a magnetic meridian through the Arava, the Jordan Valley, east of the Sea of Galilee and Mount Hermon, and another along a geographic meridian through the central Negev to the Mediterranean Sea. Benyamini called the second route especially remarkable because it ignores obvious terrain features and appears to follow Earth’s lines of longitude.
He described the species as territorial, fast-flying and low to the ground, with males defending their area from rivals. Its upper wings are blue, black and white with orange eye-like markings used to deter predators, while the underside is gray and camouflaged. The larvae feed on the host plant, adults on flower nectar, and the butterfly itself becomes food for birds, lizards, spiders and parasitic insects.
Climate change, Benyamini said, has so far helped the butterfly remain in Israel, along with southerly airflow from Red Sea lows. But small isolated populations can suffer genetic decline, and he said it is still unclear whether the former Nahal Zin population disappeared because of spraying and habitat damage or because of inbreeding. He urged protection of native vegetation, planting host plants, preserving open spaces and ecological corridors, reducing night lighting, and supporting citizen-science monitoring through Israel’s national butterfly survey.
