WASHINGTON, Maine -- 08/21/19 -- Two monarch chrysalis hang from the metal side of a dumpster at Slater Farm in Washington, Maine. The orange and black wings of the butterfly can be seen through the side of the darker chrysalis, which is just about ready to open. (Aislinn Sarnacki | BDN) Credit: Aislinn Sarnacki | BDN | BDN

“Watch your step,” said Heather Halsey, standing on her overgrown lawn. “They’re all over the place.”

This summer, monarch caterpillars and butterflies have enveloped Slater Farm in Washington, Maine. Halsey, who purchased the property in 2015, is overjoyed at the phenomenon.

“There must be thousands,” she said on Aug. 21, her head thrown back as she surveyed the side of the farmhouse. Monarch chrysalises covered the building. The pale green sachets, flecked with gold, dangled from window frames and wood siding. Caterpillars transforming into butterflies.

“They look like jewelry they’re so beautiful,” she said.

Credit: Aislinn Sarnacki

Covering about 100 acres, the historic farm features a huge field of milkweed, the only type of plant that a monarch caterpillar will eat. In addition, the farm is home to an abundance of wildflowers such as goldenrod and echinacea, which provide food to monarchs after they’ve transformed into butterflies.

Yet this is the first year that Halsey has noticed more than one or two monarchs on the property.

“I don’t know if it took several years of not mowing [the milkweed]? I think that probably has helped,” Halsey said.

The event may also be the result of a larger trend. After years of decline, the monarch population appears to be bouncing back nationwide, according to Monarch Watch, an education, conservation and research program based at the University of Kansas that tags monarch butterflies.

Credit: Aislinn Sarnacki | BDN

Saving the monarch butterfly

When Halsey purchased Slater Farm in 2015, the monarch population had just hit an all-time low.

Each winter, all of the monarch butterflies living in North America migrate south to congregate in a specific forest in Mexico. There they cling to the trees and slip into a stupor that lasts for months. This annual event has allowed scientists to easily monitor the monarch population since the mid-1990s.

At the highpoint of their population, during the winter of 1996 to 1997, monarchs occupied the trees of about 50 acres in Mexico. In the winter of 2013 to 2014, they inhabited just 1.5 acres — the smallest population ever documented.

[The butterfly effect: Monarchs continue to vanish from Maine fields]

“A lot of it is due to a loss of habitat,” said Ba Rae, a conservation specialist for Monarch Watch. “When they started putting Roundup on fields in the Midwest, the habitat just plummeted, which is a real problem. There was also some logging in the reserves [where they winter in Mexico], which is somewhat of a problem as well.”

Credit: Aislinn Sarnacki

Founded in 1992, Monarch Watch is an education, conservation and research program based at the University of Kansas that focuses on the monarch butterfly. Working with other conservation groups, the program tracks monarch migration and has established “Monarch Waystations” — habitats where these butterflies can thrive — throughout the U.S., Canada and Mexico.

While Slater Farm isn’t officially a Monarch Waystation, it has all the requirements: milkweed, sun, nectar sources and shelter.

“[When I purchased the property] I thought, ‘Well, I’m going to leave these big areas of milkweed because I know that monarchs are having a hard time,’” Halsey said.

In the past few years, the monarch population has experienced a bit of a rebound. Last winter, Monarch Watch reported that the overwintering monarch population covered nearly 15 acres.

“We’re still pretty low,” Rae said. “We had a very good year last year, but it wasn’t anywhere near as good as back in the 90s.”

A ‘magical’ experience

A nature lover, Halsey has loved monarchs since she was a little girl growing up in Fairfield, Maine.

“When I was little, I remember very clearly putting a chrysalis in a jar with my mom and my dad and watching it transform, and then letting it out and watching it fly away,” said Halsey. “It made it feel so personal and so magical, and it made them special after that. I hear a lot of people say they remember doing that.”

Halsey currently lives next door to Slater Farm, which features a beautiful but rundown farmhouse and adjoining barn, both built in the early 1800s. All along, her intentions have been to renovate the farmhouse and move in, but it wasn’t until this year that she dove into the project full force.

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While working on the house in July, she started to see the first monarch caterpillars, identifiable by their yellow, black and white stripes. They were eating the tall milkweed plants right down to the ground.

“She has been seriously blessed,” said Rae. “If she’s got a good supply of milkweed, that’s what they’re coming for, and on top of that, the adults need nectar flowers.”

Credit: Aislinn Sarnacki

One monarch can lay up to 400 eggs, Rae explained. Therefore, it would only take a handful of butterflies to produce such a large population at Slater Farm.

Once large enough, monarch caterpillars leave the milkweed to search for hard, sheltered surfaces to morph into chrysalises. At Slater Farm, many chose the house and barn. Others found the picnic table, the underside of the dumpster and the tire rims of the lawn mower. Hanging upside down, they shed their skin and in the course of 10 days, transformed into butterflies.

“It’s so symbolic of everything I’m doing here,” Halsey said. “I mean, I know it’s not personal of course, but it feels very personal.”

As the summer winds down, these large orange and black butterflies will migrate south to roost in Mexico. Halsey is curious if they’ll return to her farm next year. Only time will tell.

Credit: Aislinn Sarnacki

Aislinn Sarnacki

Aislinn Sarnacki is a Maine outdoors writer and the author of three Maine hiking guidebooks including “Family Friendly Hikes in Maine.” Find her on Twitter and Facebook @1minhikegirl. You can also...