TAMPA (FOX 13) - A monarch butterfly landing in your garden is always a special sight, but also potentially a big problem. A common consumer mistake could be killing butterflies.
“You have monarchs staying in places they're not supposed to be,” warned botany student Louie Castillo, a volunteer with the Monarch Milkweed Initiative
Botanists say the orange butterflies are not supposed to be in the Tampa Bay area over the winter. And what you're buying could be partially to blame.
“The demand for milkweed is huge,” explained Bruce Turley, a local nursery owner. “People are really interested in doing a butterfly garden.”
Consumer demand for butterfly gardens has been growing. Growing what monarchs eat lures them in. What they eat is milkweed. It's also the only place they lay their eggs.
Florida has more than 20 native species of milkweed, but good luck finding them for sale.
“Whenever you go to the store, what many of us don't realize is, you're actually buying a non-native milkweed that's native to Mexico,” said botanist Scott Davis, a ranger at St. Marks Wildlife Refuge.
When we went shopping at several big box stores in the Tampa area, that's exactly what we found: Ascleipia curassavica -- "tropical milkweed” from Mexico. It’s an easy-to-grow species that doesn't die back in the winter, and can spread beyond your backyard.
Botanists say it means monarchs no longer have a need to migrate south.
“What happens is, this produces an artificial population of monarch butterflies that would never be there without that non-native milkweed,” Davis continued. “And, as if that was not enough, it's a vector of a little parasite causing mortality in the species.”
While monarchs aren't considered endangered at this point, their population in the U.S. plummeted to an all-time low of 50 million two years ago.
“Which might not sound like a lot, but then you realize the traditional numbers were about one billion,” Castillo pointed out.
Researchers linked the decline to a drop in milkweed due to urban sprawl, and there's been a concerted effort to replant. Local nurseries tell us they're working to stock up on the right kind, so butterfly lovers don't make a milkweed mistake.
“People are just heartbroken and flabbergasted. They feel really bad,” offered Turley.
But don't worry if you have the wrong kind right now. Davis has some action you can take to help. “So what can you do as you transition, you treat as if it was native and you cut it back in the fall of the year.”
You've probably heard of the phrase "the butterfly effect" -- how one small occurrence, like a butterfly flapping its wings, can spark a chain reaction to something huge.
So the next time you shop for your garden, think about the butterfly effect -- on butterflies.
FANN, http://www.afnn.org: Help find nurseries that sell native plants.
Florida Native Plant Society, http://www.fnps.org: There are several local chapters that can help make the right choices.
St. Marks Refuge Monarch Initiative, https://www.fws.gov/nwrs: Where botanist Scott Davis works.