If you’ve been outside at all the past month, you’ve seen them or their deceptively large shadows passing overhead — brilliant, determined orange flakes making their way south toward wintering grounds in Mexico. We in Douglas County are lucky enough to live along the central migratory flyway for Monarch butterflies.

Many people in Lawrence recently attended an event at the Wakarusa Wetlands or Prairie Park Nature Center, pressing tiny identification tags onto the butterflies’ surprisingly sturdy wings and recording crucial information such as the individual’s sex and overall condition. Those butterflies recovered and returned to KU’s Monarch Watch help to unravel the mystery of their lives and arduous journey.

Though the migration peaked here Sept. 22-23, members of the fourth generation of this year’s population will trickle through the area into November, nectaring on the remaining asters, sunflowers and other flowering plants.This year’s migration wasn’t as large as in years past. Monarch Watch’s director, Chip Taylor, says this reflects the tough year the species has had overall.

An unusually warm spring brought butterflies north through Texas and Oklahoma too fast and too early. Quite a number of monarchs had arrived in Lawrence by April 10 and laid a huge number of eggs. Late spring cold snaps took a toll on the exposed caterpillars. In other parts of North America, the spring and summer were too hot and dry for Monarchs to thrive.

Taylor says Monarchs can adapt to such seasonal extremes. What they haven’t been able to adapt to is the wholesale habitat loss. Where researchers once identified logging of the butterflies’ winter roosting habitat in the oyamel pine forests of central Mexico as the primary threat to their survival, environmentalists both here and in Mexico have been able to make real progress toward protecting these areas.

Monsanto has now emerged as the Monarch’s primary enemy. A study conducted by Taylor and fellow researchers in 2000 revealed that the small amount of milkweed, the Monarch’s host plant, growing in corn and soybean fields was important habitat for them. “Though farmers disked between rows,” he said, “it didn’t entirely eliminate the milkweeds.”

However, in the last decade farmers have found themselves with fewer options. Those who planted other types of corn and soybean seeds found they had infringed on Monsanto’s patent when their seeds cross-pollinated with Roundup-ready plants. As a result, more farmers have planted corn and soybeans genetically modified by Monsanto to resist Round-up applications.

In that same decade, researchers noted a startling crash in Monarch numbers. When Roundup is applied to a field, it kills every other plant, effectively eliminating the more than 80 million acres of field milkweed the butterflies depended upon, or 30 percent of their breeding habitat. Remaining wild milkweed will not sustain Monarch populations.

This creates an urgent need for ordinary citizens, especially those of us along the migratory flyway, to plant Monarch way stations. Whether they’re in a schoolyard, corporate garden, or individual lawn, milkweed way stations have become critical to the species’ survival. You can find out more about how to plant your own way station at the Monarch Watch website: www.monarchwatch.org.