Michoacan, Mexico - July 01, 2024

Painted lady butterflies venture far and wide with their impressive migratory patterns that stretch for thousands of kilometres, but they often travel across land so they can stop to rest.

Scientists have now found evidence that a group of winged travellers flew more than 4,200 kilometres (about 2,600 miles) across the Atlantic Ocean without stopping, according to a new study published on 25 June in the journal Nature Communications.

The finding puts to rest a decade-long mystery that began when entomologist and lead author of the study, Dr Gerard Talavera, encountered about 10 American painted lady butterflies, known by the scientific name Vanessa cardui, on a beach in French Guiana in October 2013. The insects, which are not usually found in South America, were worn out and had holes and tears in their wings.

"They looked exhausted. They couldn't even fly much; instead of flying, they were jumping," said Talavera, a senior researcher at the Consejo Superior de Investigaciones Cientificas at the Botanical Institute in Barcelona. "The only explanation I could come up with was that they were long-distance migrants."

But crossing an entire ocean was unheard of for butterflies, even ones as mundane as painted ladies. Talavera, along with his colleagues, had to rule out a few factors before concluding that these butterflies achieved what was previously thought impossible.
An October 2016 study co-authored by Talavera found that painted ladies from Europe migrate long distances of around 4000 kilometres (about 2500 miles) to sub-Saharan Africa, and face obstacles such as the Mediterranean Sea and the Sahara Desert. But even so, the butterflies remain mainly over land where they can "stop and refuel, feed on flowers and then get energy to move on," Talavera said.

SHOTLIST:
1. various of the 'painted lady' butterflies.