On a poster on the living room wall in her Bangor apartment, Sarah Fletcher has written a quote from “Hope for the Flowers,” by Trina Paulus, a children’s book first published in 1973:

“How does one become a butterfly?” she asked pensively. “You must want to fly so much that you are willing to give up being a caterpillar.”

The wriggling, yellow-and-black caterpillars in the homemade net hanging from the ceiling just a few feet away embody that sentiment exactly. And it obviously rings true for Fletcher, who is a serious monarch butterfly enthusiast. In fact, enthusiast is probably too weak a word. She’s an expert – an amateur lepidopterist.

“Butterfly season is the best time of year. I look forward to it all winter. There’s that flash of orange in the summer. I live for it,” said Fletcher, who is 26, and works as a nanny for a Bangor family. “If I drive around with friends, I’ll yell at them to stop when I see milkweed.”

Monarch butterflies feed almost exclusively on milkweed, the pink-and-white clusters of flowers found in sunny, sandy areas all over eastern North America. Fletcher tramps around in the sickly sweet blossoms, investigating every petal in search of tiny monarch caterpillars. She’s deeply tanned from hours spent in the sun, collecting the bugs.

Fletcher has an easy laugh, and a patient, affable nature that comes in handy when she’s with the little girls for whom she is a nanny.

She lives a fairly normal life for someone her age. She goes out with her friends. She likes to read and to make jewelry. She lives in an apartment, which she shares with her roommate, Mike, a cat, a bunny and, at last count, more than 50 caterpillars.

And that’s what sets her apart – most people don’t spend their spare hours picking through weeds, looking for bugs to take home.

“I’ve always done it. People ask me, ‘How can you take care of something as gross as a caterpillar?'” she said. “But I don’t think it’s gross. In a few weeks, they’ll be butterflies. How can you not want to take care of something so beautiful?”

Fletcher mainly stays within the Bangor city limits, in Cascade Park, along Valley Avenue, and sometimes near Pushaw Lake. Occasionally she’ll go out to her hometown of Charleston. When she finds a caterpillar, she places it in a plastic cup with a few leaves inside for it to munch on. She covers the cup with a coffee filter held on by a rubber band and sets it on her windowsill, to wait for the creatures to grow.

When the caterpillars reach a certain size, she transfers them to the net that hangs in her living room. They eventually make their way to the top of the net, where they start the process of making a chrysalis.

“They turn into a kind of question-mark shape, and they start to shake a little bit,” said Fletcher. “You can actually watch it happen.”

Two weeks later, the butterfly emerges.

“When they come out from the chrysalis, they are all crumpled up like tissue paper, and covered in fluid,” she said. “It’ll take four or five hours for them to dry out and be ready to fly.”

The caterpillar-to-butterfly metamorphosis is a process that still mystifies and amazes Fletcher, even after more than 10 years of butterfly chasing.

“How do they go from wiggling, fat caterpillars to beautiful, gliding, flying creatures?” she pondered. “It’s phenomenal. I still don’t completely understand it.”

After the butterfly has emerged from its cocoon, Fletcher places it gently in another net, and takes it out to one of her favorite spots and releases it, like a mother bird teaching her chicks to fly. And then they’re gone, off to snack on nectar until it’s time to fly south.

The annual southward migration of monarch butterflies is one of biology’s unsolved mysteries. Year after year, flocks made up of thousands of monarchs make the journey to the same handful of wintering spots in Mexico and California. No one knows exactly how they know when and where to go – is it the position of the sun in the sky? Circadian rhythms?

“I think they are following the food. When there’s nothing left here, they go south,” said Fletcher. She hopes to make a pilgrimage someday to those winter spots to witness the throngs of butterflies.

“There are these trees that are just covered in monarchs,” she said. “I would be in absolute heaven.”

Fletcher will continue to collect caterpillars through the middle of September. By the second week in August, she had released 151 butterflies over the course of the summer.

“My biggest release so far was 16 in one day,” she said. “They just kept hatching and hatching and hatching.”

Fletcher’s love of butterflies and love of art go hand in hand – in a sense, butterflies are her creative outlet.

“There is art in nature. And I think there’s a lost appreciation for nature. I don’t think enough people even notice it. It makes me sad,” she said. “I love to be out in a field, or in the woods. Nothing makes me happier.”