Bright and ephemeral like a flittering orange ray of sunshine, the monarch butterfly is facing serious trouble. They are well-known for their annual mass migration from Canada and the U.S. down to warmer climes in Mexico, forming dense colonies before heading northward again in the spring to breed. However, according to some of the latest counts this year at their overwintering home in Mexico, the monarch butterfly population has been reduced by around 60%, the lowest in decades. A little rain usually doesn't hurt anybody, but this winter was a watery disaster for the monarch.Landslides and herbicides
Scientists are blaming the decline on torrential rains which caused severe landslides in the Mexican state of Michoacan. But extreme weather conditions are something the monarch mass migration has faced before; in fact, it's really habitat loss that is killing them - including forest degradation, poor land use (such as farming on steep slopes) and the use of herbicide in massively-expanding, genetically-modified corn and soybean farms, which eliminates wild food sources for the monarch.
Already in 2009, weather conditions characterized by drought and unseasonal changes in temperature along their migration route caused a steep decrease in the monarch population.
Mass migration in danger of disappearing
Previously in the 1990s, the butterflies occupied an average of nine hectares of forest, with an estimated density of 60 million per hectare. This winter however, they are down to 1.92 hectares, or roughly two and a half soccer fields.
"They're not in danger of extinction, but what we're really concerned about is preserving the migration because the migration is such a magnificent phenomenon," says Dr. Orley "Chip" Taylor, professor of ecology at the University of Kansas and director of its Monarch Watch program.
The bright orange pollinator also recently made the World Wildlife Fund's list of the ten most critically endangered animals, along with other more well-known threatened species like the tiger.
And the solution for helping the monarch bounce back? It may seem innocuous, but Monarch Watch has launched a campaign to get gardeners, farmers (and even people living in cities who have a bit of soil) to plant milkweed, the favoured food and egg-hatching apparatus for these butterflies. It's usually quite plentiful in the wild in many parts of North America, but milkweed is also being threatened by the overzealous use of herbicides across North America.
"It's not just the backyard garden," Taylor says. "We're hoping to encourage changes in roadside management practices, how public lands are managed and how people are managing what they would call nonproductive land or marginal land that they might own."
More on the Monarch Butterfly
Mexican Authorities Return Illegal Logs to Forest Communities
Pollinators in Peril Immortalized in Stamps, Crop Art
How to Map Migrating Monarch Butterflies
Michigan Teens Build Butterfly Houses and Plant 26,000 Native Plants through the Zaagkii Wings and Seeds Project