Monarchs on the rise

Walk into Westminster’s Butterfly Pavilion and head into Wings of the Tropics, where about 2,000 butterflies flutter in a tropical garden filled with plants, trees and humidity. 

Near the entrance there is a hatching exhibit where cocoons transform into butterflies. Peer in the window next to the display, and Shiran Hershcovich may be working in the lab with others to make community science come alive. 

Hershcovich is a lepidopterist, a person who studies butterflies and moths, and most recently, she discovered monarch butterflies may be making a comeback in Colorado.

“We are enthused to find that monarchs in Colorado showed an approximate 180% increase from the mean over the past seven years of our monitoring efforts,” Hershcovich said. 

This rise in monarch numbers in the state is the most significant increase in the past 30 years, according to the 2021 Colorado Butterfly Monitoring Network report. The network — which Hershcovich describes as “people-powered” — sends community scientists out into designated areas and trails to count butterflies across Colorado. Butterfly-monitoring programs also operate across the country, including California, Florida, Illinois, Michigan and Texas. 

This is the ninth annual report from the network, and 2021 stood out as having the highest number of volunteer hours recorded since the program’s inception.

Important invertebrates 

As pollinators, butterflies help keep ecosystems alive, Hershcovich explained. By pollinating native plants, they are propagating biological systems, and they serve as important food sources at every step in their life cycle. 

They also indicate healthy ecosystems because butterflies are picky eaters. The monarch’s host plant is milkweed, and it will only reproduce on milkweed. Therefore, if its host plant is decimated, the butterfly will be the first to disappear. 

In addition, butterflies help connect people to species of insects.  

“They are great ambassador animals,” Herschcovich said. “They can be a great gateway point into loving insects. If we started with roaches, it would be pretty hard to get people on board.” 

The monarch’s steady decline

According to Herschcovich, there are two populations of monarch butterflies: Eastern monarchs and Western monarchs, with the Rockies sitting in between the two.

And while the recent increase in monarchs is promising news, Herschcovich noted the species has been in a steady decline for decades. Since the 1980s, the Western monarch saw its population decline by 99%, and the Eastern monarch population has decreased by around 80% since the 1990s, Hershcovich said. 

Even so, the species continues to be denied federal protection from the Endangered Species Act. 

“Monarchs are one of them too, but they just didn’t make it to the priority, and they didn’t meet all the criteria, I guess,” she said. 

Without government protection, Hershcovich said, conservation becomes vitally important, and that’s where community science can make a difference. 

Volunteer conservationists 

Community scientists can be anyone — a neighbor, a teacher, the average Joe. All it takes is some time to train and explore. 

Steve Chady, the Pavilion’s longest serving volunteer at eight years and a wannabe lepidopterist since age 12, is one of those community scientists. Between May 15 and Sept. 15, he heads out to Broomfield County Commons Park six times to complete the same walk while counting as many butterflies as he sees. 

“If you enjoy outdoors and you’re passionate about the environment, it’s a way to contribute to conservation,” Chady said.

“Everyone comes with a built-in scientist,” Hershcovich said. “Science is just being curious and having that sense of exploration and looking for answers.” 

Without 61 volunteers counting butterflies across Colorado, the monitoring study would not be possible, and the effort is always looking for more volunteers. In total, the group counted 124 Eastern monarchs in Adams, Arapahoe, Boulder, Broomfield, Douglas, El Paso, Gilpin, Jefferson, Larimer, Ouray, Routt and Weld counties. 

“We only know those numbers because of community scientists, so it’s people dedicated to the cause, who are going out and donating their time to count monarch populations,” Herschcovich said. 

She said the percentage increase in monarchs recorded this year took into account volunteer hours to provide a more accurate number. Because the report relies on volunteers, some years see more hours counting butterflies than others.

Counting butterflies aids conservation efforts. Herschcovich noted that conservation can seem like a major problem with only major solutions, and she sees that line of thinking applied to climate change as well. Yet, she believes some answers can be simpler than most folks may think. 

“Community scientists really take matters into their own hands and revolutionize what we can do for conservation,” she said. 

Climate change, wildfires, droughts, urbanization, herbicides and many other factors contribute to the decline of butterflies, and Hershcovich said it all comes down to habitat. 

“When there are big droughts and water sources disappear or diminish, the host plant (ex. Milkweed) habitat also diminishes, and when we expand urban zones, we also essentially erase healthy habitat for monarchs, and when we plant gardens instead of planting native plants — we put grassy lawns — that’s also removing additional habitat,” she said.

She said the 2019 and 2020 fire seasons were probably linked to the large declines during those years.

On the flip side, she explained the increase in monarchs — both nationally and across the state — is likely due to more favorable climate conditions such as milder temperatures during the breeding season and better rainfall.

She also noted decreased use of pesticides and more monarch conservationists planting milkweeds and native flowering plants to support the species as other factors contributing to the rise in monarch numbers.

“While it’s difficult to point to a single cause of increase, it’s likely an aggregation of behaviors and conditions that have boosted monarch numbers around the country,” she said.

Colorado residents can help restore monarchs and other butterflies by planting native plant species in their own yards, and the Pavilion has those plants for sale in the spring.  

“Everyone gets to participate in creating a safer world for monarchs and invertebrates in general, and really ecosystems,” Herschcovich said.