By Pat Garber
Looking out my front door last month I saw, fluttering among my lantana and ruella blossoms, one of my favorite creatures, a monarch butterfly. The numbers increased as autumn progressed, their arrival synchronized with the blooming of the seaside goldenrod on the island.
Late September on Ocracoke sees the advent of one of Mother Nature’s great annual events–the migration of monarch butterflies. All over the United States these lovely insects are on the move, with the eastern population heading to groves of fir trees in Mexico, where they will congregate by the millions.
Where monarchs went in winter was a mystery until the 1970s when 60 million to 1 billion butterflies were discovered in the oyamel fir trees in central Mexico. Tagging projects across the country are trying to learn more.
In recent years, monarch populations have plummeted nationwide from near 1 billion to less than 33 million.
Dr. Orley “Chip” Taylor, the University of Kansas professor who heads “Monarch Watch,” emphasizes that we may be on the brink of an immense ecological disaster. Monarchs, he says, are a keystone species, symbolic of other wildlife endangered by the loss of habitat in this country. Seventy percent of all vegetation requires pollination, and there will be a biological cascade if these species are destroyed.
Butterflies and other pollinators are necessary to maintain the infrastructure of all wildlife.
As a result of the decline, leaders from the United States, Canada and Mexico at a summit last February declared the monarch an “emblematic species which unites our three countries.”
In August, three organizations along with monarch researcher Lincoln Brower petitioned the U.S. Fish and Wildlife Service to list the monarch butterfly as “threatened” on the Endangered Species List.
Part of the problem lies in Mexico. Matt Collington, environmental education manager at Airlie Gardens in New Hanover County, says that while 70 acres at the wintering site are protected as a world heritage site, the butterflies are impacted by the “edging effect.” Logging all around the site by farmers cutting down rain forests removes the buffer zone which protects it, leading to colder, harsher winters that the butterflies cannot survive.
Monarchs feed on various species of milkweed
Brower’s research suggests that a major cause of the decline lies in the United States where agricultural practices have practically wiped out the milkweed.
From 2008 to 2012, an area the size of Indiana was plowed and converted to corn fields, according to Taylor. In North Carolina, hog farms have displaced fields where milkweed, goldenrod and other nectar plants grew.
Kathy Mitchell, director of the Monarch Project at the NC Aquarium in Manteo, believes the reason for monarch decline includes agricultural use of herbicides, home-owner use of pesticides and residential mosquito control programs.
The butterflies that migrate through the Outer Banks usually arrive in May or June and again in September and October.
Martha Flanagan, coordinator of the Living Conservatory at the North Carolina Museum of Natural Sciences in Raleigh, says that a small, stable population of monarchs stays if resources are favorable, and do not continue migrating.
Though there have been seasons where monarch caterpillars have been thick locally, Mitchell says she did not see any monarchs this spring, and that few have been spotted in Currituck, Edenton or Southern Virginia. 2013 had the lowest numbers of monarchs in years, she said, and there have been fewer butterflies in general.
“2014 is by far the poorest year for butterflies (including monarchs) that I have witnessed since I began butterflying in 1991,” says Harry Legrande, author of “Butterflies of North Carolina.” He attributes this to unusual weather patterns and extremely cold winter temperatures, but says only time will tell.
On the positive side, says Collington, there is great interest among homeowners who want to help butterflies by planting milkweed and other native species.
“Conservation and restoration of milkweed needs to be a top priority,” Taylor says.
The Natural Resource Defense Council is asking state and county highway departments to plant milkweed and refrain from mowing and using herbicides.
Individuals can limit the use chemical herbicides in their yards, allow native plants such as milkweed and goldenrod to grow, plant host and nectar plants for monarchs in yards, schools, parks, and roadsides, and encourage others to do the same.
Important host plants include seaside goldenrod, narrow leaf, or swamp, sunflowers, wild asters, black-eyed susans, and coneflowers. Some of these are available at the Ocracoke Garden Center.
Entomologists predict that the coming year may see more monarchs a result of growing concern and action, and Brower emphasizes that it is not too late to save the monarchs, but that steps must be taken now, “while there is still time.”
This is a very informative article on a scientific subject that should be of concern to everyone. Since I had already viewed the NOVA documentary, “The Incredible Journey of the Butterflies” on PBS I had some acquaintance with the facts and issues. I found your article to be carefully documented and well written.
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