(Radio Iowa)- The number of monarch butterflies wintering in Mexico dropped this year. Nicole Shimp with Iowa State’s Monarch Conservation Consortium says they can tell the population by the number of monarchs in the tree canopy. “The space that they occupied in Mexico in the forest in their wintering grounds decreased by about 22 percent,” she says. “Last year, we were around seven acres. This year, we’re a little under five and a half acres.” Shimp says “You always had a little sadness with it, because last year, we saw just, you know, the population kind of held steady, which we thought was a pretty good sign. And so we were hopeful this year that it would maybe hold steady again, or increase a little.”

She says scientists estimate there needs to be a long-term average of about 15 acres to sustain the monarch population. Shimp says the monarch populations have dropped because of a loss of habitat down in Mexico, and loss of habitat in the Midwest where they spend their summer. She says this report shows the urgency to create more habitat continues. “This means that we need to continue to reinforce that the monarchs still need our help, and they’re still around, we just need to help them out a little bit to get the population back up,” she says. Iowa has been part of the effort to restore habitat, including the milkweed, which is the plant the monarch caterpillars eat and lay their eggs on.

Shimp says the Iowa Monarch Conservation Consortium report shows good things are happening here. “It showed between 2018 and 2020, that Iowans added 430-thousand acres of habitat in the state. And we even have a dashboard that you can go to that can show you it by county to county to kind of break it down if it’s agriculture, urban. So we have it broken down by different areas, and just seeing how many of those acres have gone in,” she explains. Shimp encourages everyone to register their monarch habitat. “If you have already put in habitat, but to make sure that your habitat is being recorded. So you can do that by we have an app called Habi-Tally,” she says. You don’t even have to be in the state of Iowa. You can put in your habitat into there and it walks you through how to do it.”

You can find out how to create a monarch habitat at: monarch.ent.iastate.edu.