Monarch Butterfly Populations Are Dwindling, But There's Still Reason For Hope, Says Butterfly Advocate

Twenty-four years ago, Monika Maeckle bought a small property on the Llano River in Central Texas as an escape from fast-paced San Antonio. A journalist and marketing professional by trade, she didn’t at first realize the value of the location on which she and her husband would later build their ranch. She also had no idea how this decision would eventually transform her life.

One October evening a few years later, a friend invited Maeckle to their nearby house, which sat on a watershed with several large cypresses. “All these butterflies dropped from the sky and started to gravitate toward the trees,” she recalls. “Stronger people who could swing a big 12-foot-long pole began trying to capture them, and we waited. By the end of the evening, we’d tagged a couple hundred butterflies, and I left there enchanted."

Maeckle recognized some of the potential geographic similarities between her ranch and her friend’s and wondered if her waterside land might also serve as a stop on the “Texas Funnel,” a wide flyway that monarchs follow as they wing south from Canada and the northern U.S. states. The rugged groups of these black-and-orange insects take off in late summer and early fall, following this path of up to 2,800 miles that will ultimately lead them to forest colonies in Mexico. The journey is a treacherous one, with many butterflies never arriving at their intended destination. Still, these majestic creatures flit and float their way through it every year—and then fly back come spring.

The butterflies had, in fact, been around Maeckle’s home the whole time, but she had never noticed them before. “We went kayaking at our usual spots, along a grove of pecan trees. I looked up, and the butterflies erupted,” she recalls. That night, she tagged 50 of them. Maeckle went on to launch Texas Butterfly Ranch, her attempt to raise awareness about monarchs; encourage conservation efforts; and have conversations with fellow advocates to track, study, and ultimately help these butterflies survive the shifting sands of their environment.

Last fall, however, researchers recorded the second-smallest roost since measurements started in 1993. Masses of these tiny animals covered just 2.2 acres of the Monarch Butterfly Biosphere Reserve in Michoacán, Mexico, a 59% decrease over the previous year’s low number and only slightly above the 1.7 acres from the 2013 season.

This downward trend is nothing new for those who carefully monitor the annual voyages. But Maeckle, whose book, The Monarch Butterfly Migration, was released in August, argues that insect populations are quite volatile, “bouncy” even. Some years are better than others, but in the more than three decades of data, the numbers have been on a steady decline.

The effects of climate change have had tremendous implications for butterfly populations, as monarchs lay their eggs exclusively on milkweed plants. Droughts, floods, and other extreme weather conditions have destroyed these roosting and breeding grounds. Use of herbicides has had similar impacts, and forest destruction in Mexico is shrinking the size of their wintering sites.

All of this bad news drowns out some of the good: Scientists in South Carolina have identified a group of monarchs that live year-round in the state’s swamps and Sea Islands. These butterflies, like the ones in Texas, rely on native species of milkweed plants, but they don’t leave. Their “migration” spans a relatively small area in comparison to the transcontinental trek of their peers. In California, there were only a couple thousand monarchs recorded in 2020, but the most recent data shows a dramatic increase to about 330,000.

Those stories, Maeckle notes, offer reason for hope. After nearly two decades of research and observation since her first sighting in those cypress trees, she firmly believes these insects are changing and evolving but not disappearing. “Whatever this next chapter holds for monarchs, they’re going to be around. They will still be with us,” Maeckle says. “They’re just morphing to the next stage.”