Study led by Iowa State University takes new look at monarch numbers

August 27, 2019

A long-term study offers new insights on how monarch butterflies are doing as they journey through the state, based on research by Iowa State University and the Iowa Department of Natural Resources. The research provides evidence that reduced butterfly populations on the breeding grounds here in Iowa is one reason for the species’ overall decline, as well as habitat loss on overwintering grounds in Mexico. The results are based on data collected from 2006-2017 at more than 400 sites across Iowa.