1:07 PM EDT, June 10, 2013
Deep in mountainous evergreen forests of central Mexico, surveyors this winter measured hectares of oyamel trees, or “sacred fir,” where monarchs — some in clusters dense enough to bend younger trees or break branches — huddled together to overwinter.
The news: The nine hibernating colonies occupied a forested area 59 percent smaller than the previous census taken a year before.
“With the presence of the monarchs, the dynamics of nature changes since these visitors modify the look and, more important, they modify the ecology — the interaction between living creatures — of the hibernation forests,” said Eduardo Rendón Salinas, head of the monarch butterfly program at World Wildlife Fund Mexico.
“During the winter, the monarch butterflies are the key species that determines the behavior of plants and animals in these ecosystems.”
It’s not just a matter of ecology in Mexico, but a concern across the continent, he said.
“One of the most important functions of the butterflies in general is that of pollination, whose result is the reproduction of plants and hence the productivity of ecosystems,” Salinas said. “Plants are the original producers of energy in trophic chains (or food chains) that are the basis of the functioning of ecosystems. Therefore the function of pollination of the monarch butterfly in North America is essential for the productivity of all flowering plants of species that these butterflies find on their way.
“If butterflies were missing, the natural ecosystems of our continent would be affected.”
Finding a solution, including pinpointing parasites and protecting habitat, will require leadership in Mexico, the U.S. and Canada, he said. World Wildlife Fund Mexico, in partnership with Mexican telecommunications company Telcel, is working to conserve hibernation forests in Mexico, but members also are collaborating with scientific and conservation leaders in the United States and Canada to conserve the monarch butterflies’ reproduction habitats and migration route.
The group also is a founding partner of Monarch Net (monarchnet.uga.edu) and part of a research team that includes the University of Michoacan in Mexico, Minnesota University, Emory University and others.
At the University of Kansas, professor Chip Taylor, founder of the education, conservation and research program Monarch Watch, said the greatest threats to monarch migration are shrinking habitats in the U.S. and Mexico, along with increased herbicide use in row crops where monarchs once found habitats. The group and its volunteers tag butterflies to better understand population numbers and migration routes.
The organization’s Waystation Program offers volunteers around the country seed kits and guidance on creating monarch habitats. More information about the tagging and habitat program is available here: monarchwatch.org/waystations.