We’ve seen some information on how much people value monarch butterflies. Now we’re learning that the beautiful orange lepidopterans have their own citizen science Thanksgiving count and might soon be labeled as a threatened species under the Endangered Species Act if a petition has any effect.
Beloved by tattoo parlors and fantasy princess landscapes, the king of butterflies is in decline. During their annual migration, monarch butterflies are famous for gathering in innumerable flutters as they fly from summer breeding grounds in the U.S. and Canada to warmer sites in Mexico and California. At one time, there were over a billion monarchs making this journey. Now, less than 4% are left.
Over the years, human behaviors, particularly agricultural practices have contributed to the monarch’s decline. In a petition to protect monarchs scientists point to habitat loss as grassland is converted to farmland and overwintering sites are deforested as a major factor. On top of that, the cultivation of certain genetically engineered crops enable farmers to apply broad-spectrum herbicides killing weeds such as milkweed, the monarch caterpillar’s sole food source.
Unlike honeybees whose population decline directly affects agricultural production, the decline of monarch butterflies may have gone unnoticed if not for the efforts of scientists and conservation groups. Every winter, The Xerces Society for Invertebrate Conservation counts overwintering western monarchs, a subset of monarch butterflies west of the Rockies. The butterflies arrive at the California coast as early as October and remain until spring.
Counting butterflies might sound fanciful, but scientists need a complete survey to understand how the current butterfly population is faring. “There are over 400 identified overwintering sites, half of which are registered and active monitoring sites. It is a large geographical range for a small organization like ours to cover,” says Candace Fallon, a conservation biologist with The Xerces Society. To handle the work load, the group enlists citizen scientists to visit designated sites and count the number of monarchs present, or as the case may be not present. “We depend on volunteer assistance to gather data. We couldn’t do this important work without them.”
You can read the rest of the article here.