The story below is an excerpt from our Sept./Oct. 2014 issue. For the rest of this story and more like it subscribe today, view our digital edition or download our FREE iOS app!
Each year for the past two decades, Bill Haley has spotted about a dozen monarchs during the seasonal butterfly counts he’s led in southeast Tennessee.
“Last year, we didn’t see any monarchs at all in the spring,” says Haley, education outreach coordinator for the Tennessee Aquarium and founder of the Tennessee Valley chapter of the North American Butterfly Association. “Their numbers are so reduced that we’re just not seeing them.”
Haley’s experience is merely a microcosm of a much bigger problem: Monarch populations are on the decline. According to the first records kept of the insects’ wintering grounds, about 1 billion monarchs covered 17 acres of fir forests in the mountains of Mexico in early 1994. By the winter of 2012-13, that acreage had dwindled to three. This year, only 1.65 acres of the winged beauties were found.
“There’s not just one cause,” says Haley. “It’s a whole bunch of things that are kind of ganging up on the monarchs to knock them down.”
For one thing, excessive heat and drought conditions in Texas, where most migrating monarchs funnel into Mexico, have dried up once-reliable nectar sources. What’s more, the deforestation of Mexican mountainsides has altered microclimates where the butterflies routinely winter, making them more susceptible to violent weather and quick drops in temperature.
