Ranching beetles, fighting invasive species

This story was originally covered by PRI’s Living on Earth. For more, listen to the audio above.

Beetles are usually feared by naturalists for their destructive, tree-eating ways. For volunteers at the office of the Neponset River Watershed Association, however, beetles may represent a secret weapon to save plants from the invasive purple loosestrife plant.

Purple loosestrife plants, and their beautiful purple flowers, are choking wetlands in the United States and killing native species like cattails. The plant invades some 300,000 acres in the U.S. each year — an area comparable to the size of Los Angeles — and has been spotted in 49 states. It has no natural predators in the United States, which allows the purple loosestrife to proliferate unimpeded. Georgeanne Keer, a project manger for the Massachusetts State Division of Ecological Restoration, told PRI’s Living on Earth:

It’s here and there is nothing in our environment that’s controlling it. And so we needed to find something that would actually keep it in check so that the other species can regain the competitive edge.

In the search for tools to fight the purple loosestrife, naturalists began importing galerucella beetles from Europe. Scientists have found that galerucella beetles eat only purple loosestrife, and the animal was approved as a control organism in the United States since the 1990s.

The beetles have been released in 35 states, and the demand for more is high. Keer told Living on Earth, “There’s a high competition for beetles… and so ranching or rearing, albeit a quirky term, became an option or another resource or tool.”

Volunteers at the Neponset River Watershed Association are responding to the call, helping raise and release thousands of galerucella beetles into the Massachusetts area. “It was enormously frustrating that there was nothing we could do about it,” one volunteer told Living on Earth. “And when we heard about this project it was just a no brainer to get involved.”

Many believe the efforts are working, too. According to Carly Rocklen, a conservationist with the Naponset River Watershed Association: “It’s far easier to see a variety of plants now than it was several years ago when most of what we were seeing was purple loosestrife.”

Hosted by Steve Curwood, “Living on Earth” is an award-winning environmental news program that delves into the leading issues affecting the world we inhabit. More “Living on Earth.”