Schoolchildren and seniors are pushing to undo an ecological catastrophe threatening monarch butterflies — by planting the milkweed that monarchs need.
The dwindling of migrating monarchs has been so swift that federal scientists say farmers, utilities, homeowners and public-land managers also must get involved. U.S. Fish and Wildlife Service officials estimate monarchs have declined by about 95 percent since 1996, to 33 million from 1 billion.
“We were hoping to see one or two monarchs this year. We didn’t see any,” said teacher Allison Cole at Flagstaff Academy in Longmont, one of several Colorado schools where students have planted milkweed gardens.
An emerging national strategy calls for creating milkweed safe havens and butterfly “highways” for the orange-black-and-white monarchs.
While monarchs draw nectar from many flowers before laying eggs, their caterpillars can survive only on milkweed. Monarchs’ 3,000-mile migration from Canada through the United States to wintering sites in Mexico requires multiple generations of butterflies because each can fly only about 100 miles.
The butterflies are victims of prairie conversion and increasing use of glyphosate herbicides. These herbicides, sprayed on crops genetically modified to withstand them, kill other plants, including the milkweed that once served as habitat for pollinators such as butterflies, bats and bees.
In August, a coalition of species and food security groups petitioned the federal government to grant monarchs “threatened” status under the Endangered Species Act. But protection under that law can take more than a decade — too slow to stem monarchs’ precipitous decline.
“People are thinking, if we plant rows of milkweed along fields, highways or anywhere we can be planting, that will provide more stopover places,” said Gina Glenne, a Fish and Wildlife Service botanist based in Grand Junction. “We think the butterflies were doing fairly well before the 1990s. But we don’t have the milkweed now because we spray these crops.”
President Barack Obama in June launched a White House initiative to save pollinators, warning their demise could ruin agriculture and the broader economy. Obama convened bee and butterfly experts to develop a strategy, due in January, and is coordinating with leaders in Canada and Mexico.
Those working on the strategy are leaning toward efforts to mobilize communities widely to restore plant diversity bit by bit — on fallow farm fields, in parks, under power lines, on federal land, along roads and at senior centers and schools, said University of Kansas professor of ecology and evolutionary biology Orley Taylor, who serves on a presidential committee.
Taylor runs Monarch Watch, which is working with 208 schools and nonprofits to plant milkweed. Monarch Watch this year sent 600 milkweed plants, grown from native Colorado seeds, to schools and neighborhood coordinators around Colorado. Eastern Colorado lies at the western edge of monarchs’ Midwest migration route from mountains in Mexico to Canada. Western Colorado lies at the edge of monarchs’ western migratory route.
“We’ve got to get people to plant milkweed all over,” Taylor said. “We’re not going to save this species unless the public gets involved. Saving the monarch butterfly has to become a national priority.”
In addition to students at about a dozen schools, senior citizens along the Front Range have mobilized to plant milkweed, said horticulture director Amy Yarger at the Butterfly Pavilion in Westminster.
Residents at more than 50 senior centers have created gardens, she said. A Colorado Butterfly Monitoring Network of volunteers in 2013 counted butterflies at eight sites, increasing to 50 sites this year.
A Butterfly Pavilion team planted a milkweed garden for noncaptive butterflies that drew monarchs. And pavilion staffers this winter are using a Westminster greenhouse to accelerate production of milkweed — joined by the students at Flagstaff Academy — for expanded gardens and distribution to families this spring, Yarger said.
“The real impact is going to come when all the individual gardeners encourage municipalities not to spray milkweed and kill it,” Yarger said. “We should allow milkweed along roads and in ditches, not mow it down, not spray it. This absolutely can be done.”
Bruce Finley: 303-954-1700, bfinley@denverpost.com or twitter.com/finleybruce
