October 05, 2024

Early mowing contributes to monarch butterfly decline

To the editor,

City staff has done it again at Agnes Patterson Park. They prematurely mowed down habitat. Their current annual method contributes to the decline of various species, specifically the Monarch butterfly. That natural habitat recently mowed contains hundreds of milkweeds, the only survival food for which monarch butterflies lay their eggs on. In turn for the monarch caterpillar to consume and later transform into a chrysalis and then become a butterfly.

Walking around Agnes Patterson Park we were very excited to see so many milkweeds that had thriving monarch caterpillars. Each year is getting harder and harder to locate. Another walk a few days later was disappointing. A mower had ruined the chance of survival for hundreds.

According to the Nov. 22, 2013, New York Times Sunday Review “The Year the Monarch Didn’t Appear” by Jim Robbins the monarch is on a severe decline. Two studies have showed that Iowa specifically has lost 60 to 90 percent of its milkweed due to the changes in the agricultural landscape and replacing natural habitat with roads, parking lots and grass lawns. By November 2013, an estimated 33 million showed up in Mexico vs. the previous year’s record low of 60 million. A May 8, 2014, online article found on The Nature Conservancy web site “The Endangered Migration of Monarch Butterflies” says that this year’s monarch migration area was the smallest in 20 years. They have declined as much as 81 percent from 1999 to 2010. The article continues about the importance of restoring monarch habitat to prevent further decline. Jan. 29, 2014, Washington Post “Monarch butterflies keep disappearing. Here’s why” reflects much of the same information.

Twenty years ago about 2 billion monarchs would spend winters in the Mexico mountains taking up about 45 total acres. That has decreased steadily to an estimated 33 million and spread out in couple of acres and may be lower yet this November. The monarch numbers continue to drop. People can help the monarch’s chance of survival by planting a form of milkweed in their gardens.

Perhaps Agnes Patterson Park maintenance could wait until late September, well after the monarchs have started their migration to Mexico before they begin to mow those tall grasses that contain hundreds of milkweeds with monarch caterpillars on them.

Jerry and Natalie Balek

Newton