For the first time ever, the migratory monarch butterfly (Danaus plexippus plexippus) has been added to the International Union for Conservation of Nature’s (IUCN) “red list”, categorized as endangered. The IUCN was created in 1948 and is now recognized as the world's largest and most diverse environmental network, with more than 1,400 member organizations and 15,000 experts. According to the IUCN website, they are effectively known as “the global authority on the status of the natural world and the measures needed to safeguard it.”
The migratory monarch butterfly is known for its annual migration of thousands of kilometres, from wintering in Mexico and California to breeding grounds throughout Canada and the United States during the summer. The native population of this species has been found to have shrunk by between 22% and 72% over the past ten years.
Three main contributors to this species’ current situation have been identified, including loss of habitat, climate change, and the use of pesticides and herbicides.
Extensive swathes of the monarch’s winter habitats in Mexico and California have been destroyed through logging and deforestation to make way for urban and agricultural development. Widespread use of pesticides and herbicides across the butterflies’ range kills both the butterflies themselves and milkweed, the only plant that the caterpillars of this species eat and the only plant in which these butterflies will lay their eggs. Climate change brings multiple threats, including drought, negatively affecting milkweed growth, increased frequency of catastrophic wildfires, extreme weather, and excessive temperatures triggering early migrations out of synch with the milkweed growth cycle.
There are some actions that people can take to help the monarch population. Planting native species of milkweed while reducing the use of pesticides and herbicides is beneficial. Planting nectar plants like asters, goldenrod, cosmos, and black-eyed Susans will help to fuel the monarchs’ migration to their winter habitat and help them to store fats to help them survive. Taking action to protect the monarchs’ winter habitats is also beneficial but difficult to accomplish from so far away.
Dean LaBerge, Local Journalism Initiative Reporter, Grizzly Gazette