A Wilder View: New study details monarch butterfly populations

monarch butterfly
Posted at 11:14 AM, Jun 15, 2022

MISSOULA - Famous for its seasonal migration in the millions, the brilliantly colored monarch butterfly is one of the most recognizable and well-studied insects on the planet.

Missoula Butterfly House and Insectarium Development Director Glenn Marangelo explains that people have gravitated toward monarch butterflies because of their population decline.

“It's kind of the poster child for insects in a lot of ways because people like butterflies in general. The monarch is a beautiful butterfly. It's got an amazing life story -- a huge incredible migration -- and so it's a great ambassador to get people to pay attention to insects,” Marangelo said.

Over the past few decades, the monarch butterfly populations have steeply declined with some populations decreasing by 99%. This steep decline has prompted conservationists to advocate for them to be on the Endangered Species List.

“There's efforts stating that they should be listed. Some people [are] saying that their populations aren't doing as bad, some people saying that they're in really bad shape, some people saying that they're hanging on,” Marangelo said.

“In general, a downward trend over the last couple decades. The numbers are way, way down from what they were 20 to 30 years ago. I think it's safe to say they're not doing well for a variety of reasons. Again, they're kind of that poster child for what's happening with a lot of insects,” continued Marangelo.

But a new study is suggesting that monarchs may not be in as detrimental shape as we once thought. The study published in global change biology found monarch numbers are showing an increase in numbers at their summer ranges even when their wintering grounds show a decline.

“I was very excited to read a report that did say they're doing better than most people thought. Because I'm usually reading reports that say the opposite,” Marangelo noted. “I'm definitely skeptical and not saying that we should pop the champagne just yet because one year -- or a slight trend of improvement -- doesn't mean that they're doing good for the long haul.”

Marangelo advocates that the increase is most likely due to heightened conservation efforts. “If they are doing a little bit better it probably speaks to what people have been trying to do to improve their habitat or decrease the threats that are against them which is a really good thing.”

Milkweed is a great source for monarch caterpillars but there’s more you can do than just planting milkweed.

“Planting wildflowers in general because they're going to lay their eggs, and the caterpillars only eat milkweed. But, nectar [comes] from a whole variety of different flowers,” Marangelo said. “So having a lot of blooms available when monarchs are in your area is a good thing.”

Community involvement is a major driving factor in helping wildlife out and even more so for such tiny animals.

“I think the more people that work together and understand the need and education behind what we need to do for insects the better because then more people will have better backyard habitats which really do make a difference for insects,” Marangelo said.

Monarch butterflies may be in the spotlight, but many insects are in clear decline. And no matter how large or small they all play a part in our world. “They all have a role to play. They might be a really important pollinator,” Marangelo noted.

"Monarchs have opened people’s eyes to something even as common as insects. "There's no guarantee that they're doing well or if they're going to be here forever. So, the monarch has really shed light on that,” Marangelo concluded.