Monarch overwintering numbers rebound

February 28, 2016 9:11 AM
Blog Post

The overwintering monarch population in Mexico was reported last week and has increased for the second consecutive year (Figure 1). Four hectares of forest (9.9 acres) were covered with monarchs, up from the low of 0.7 hectares in the winter of 2013-14. While this is good news, the low numbers still place the butterfly at risk to a variety of threats. The Iowa Monarch Conservation Consortium is developing science-based guidelines to enhance the Iowa landscape to support monarch reproduction.

The overwintering monarchs will begin their journey north in March, traveling as far as Texas before mating, laying eggs, and then dying. The new generation moves north to repopulate the summer breeding area, typically arriving in Iowa in May.




Bob Hartzler Professor of Agronomy

Dr. Bob Hartzler is a professor of agronomy and an extension weed specialist. He conducts research on weed biology and how it impacts the efficacy of weed management programs in corn and soybean. Dr. Hartzler also teaches undergraduate classes in weed science and weed identificatio...