In the early days of the pandemic, when most people couldn't travel anywhere, Lucas Foglia became obsessed with the butterflies that go almost everywhere. 

Painted lady butterflies, found on almost every continent, are among the planet's most prolific travellers. One population, in particular, makes an epic, multigenerational journey every year from Europe to Africa and back.

So in 2021, as soon as Foglia was able to board a plane, the San Francisco Bay Area photographer set off for Italy to find the butterflies that had captured his imagination, and work with the scientists tracking what's believed to be the world's longest butterfly migration route.

But the result of that journey, the photography book Constant Bloom, is as much about humans as it is about butterflies, says Foglia. 

"In the beginning of the project, I thought I was going to just photograph butterflies and follow them wherever they went," Foglia told As It Happens host Nil Köksal.  "But pretty soon I realized that the longest butterfly migration now depends on people."

In his book, Foglia explores not only how human activity impacts the painted lady's migration route, but also the parallels between the butterflies' movements and the vast and perilous journeys that people make across borders every day in search of security and sustenance.

"When I look at the photographs, I think about both what they are and what they teach me," he said. "It's been a transformative journey, to say the least."

Painted lady butterflies 'incredible to see' 

Painted lady butterflies migrate with the changing seasons, chasing the warm weather so they can have a constant supply of nectar upon which to feast, and favourable conditions to mate and reproduce — hence the book's title, Constant Bloom.

In North America, they travel between Canada and Central America. In Asia, they cross the Himalayas. And in Europe, they make a nearly 14,000-kilometre round trip between Scandanavia and sub-Saharan Africa, crossing both desert and ocean, in a journey that spans between eight and 10 generations. 

"Painted lady butterflies are really special in how far they migrate, and that they have these really large populations," biologist Megan Reich, a post-doctoral researcher at the University of Ottawa who studies their European-African migration, said Foglia.

"They go through these outbreak cycles, and they'll make the news because there's so many butterflies passing through a city and it's really incredible to see."

The species even once made a 4,200-kilometre transatlantic journey across the ocean from West Africa to French Guiana in South America, likely blown off course by wind currents to one of the few places on the planet they're not supposed to be. 

Reich was part of the international team who mapped that journey by analyzing wind patterns, sequencing DNA of the pollen grains they carried, and analyzing the isotopic compositions, or chemical signatures, of their wings. 

"It's quite incredible that the butterfly was able to survive this journey," she said. "We figured it spent five to eight days flying over the open ocean."

Looking for butterflies, and finding human stories

That resilience is something Foglia came to admire deeply about the painted lady as he spent nearly four years traversing 17 countries to capture images of the butterflies and the people and places they intersect with.  

"I don't look for butterflies. I look for what butterflies are looking for," he said. "So I would first look for flowers."

But climate change and human encroachment into wild habitats means wildflowers aren't always blooming when and where they're supposed to.

"As droughts and other weather has become unpredictable, sometimes it's been harder to find them along the route that their migration has travelled for millions of years," he said.

But the butterflies have adapted. Foglia, therefore, frequently found himself in parks and gardens, and other places where people are, striking up conversations.

"People like butterflies," he said. "And when they learn that the butterflies they're seeing outside are travelling across the world to get there, it was meaningful for people to hear and learn about, and then think of themselves as connected to other places across borders."

Crossing borders

While photographing butterflies in the Roman ruins of northern Jordan, Foglia met a group of Palestinian and Syrian refugees making their own migration.  

"I saw flowers blooming in between the stones of these Roman ruins and thought that the butterflies had been flying to those flowers for millions of years before the Roman Empire had risen and fallen," he said. 

"And the layers of politics and power and history in that place stuck with me."

His journey eventually took him to Tunisia on the coastline of the most northern tip of Africa.

"I saw butterflies on these beautiful purple flowers in between charred trunks of trees that had burned in a wildfire," he said. "And the butterflies would drink nectar from those purple flowers, and fly across the Mediterranean Sea."

That Mediterranean crossing the butterflies make so freely is now the deadliest human migration route in the world. More than 28,000 people have died making the journey since 2014, according to the International Organization of Migration, including 2,452 last year alone.

While in Tunisia, Foglia met met a group of teenagers who spent the afternoon with him looking for butterflies. He photographed the youths with Mediterranean as a backdrop.

Later, one of those boys set out on a journey of his own along that deadly route, following in the butterflies' path.

"[He] called me on WhatsApp a few months later, telling me that he had gotten to Italy on a boat and asked for help — and also asked if the butterflies had gotten there safely," Foglia said.

"That transformed the project for me. I felt like I had to interweave those photographs of people migrating alongside ... the photographs of butterflies migrating across the sea."

The images from Constant Bloom are currently on display at the Fredericks & Freiser Gallery in New York City.

Foglia, meanwhile, says his time chasing butterflies across borders has compelled him to action. He now volunteers for refugee resettlement organizations, and donates his photographs for them to use in their advocacy.

"If I was talking to my grandchild, I might say that I did a project at a point in history when a lot of people and countries were isolating themselves and borders were strong and militarized," Foglia said.

"The lesson I got from following painted lady butterflies across countries and continents was that both people and nature are connected across borders. And because we're connected, we all share a responsibility to care for nature and each other."