Beetles, Welcomed in Arizona to Help Save Water, May Also Wreak Environmental Havoc

Tamarisk beetle
(photo: Glen Canyon,
National Park Service)

ALLGOV | Jul 17, 2014 | Noel Brinkerhoff, Steve Straehley

The tamarisk beetle has been both a blessing and a curse in the American Southwest.

The agricultural industry and state water officials in Arizona have welcomed the insect because of its appetite for the tamarisk tree, a non-native species that critics say uses too much water, up to 200 gallons a day.

The trees, also known as salt cedars, have sprung up along the Colorado River in Arizona. Tamarisks, which are native to Asia and the Middle East, were imported years ago to stem erosion. With Lake Mead, the source of water for most of Arizona, at its lowest point since its construction, authorities are looking for a way to get more water flowing downstream and taking out the thirsty tamarisk looks like a good way to do it.

So man is putting another species into the ecosystem. The tamarisk beetle was introduced in Colorado about 10 years ago and has worked its way down to Northern Arizona. It’s starting to do its work there, eating tamarisk leaves and leaving dead trees in its wake.

But ecologists argue the beetles’ introduction will only cause other problems, demonstrating the complicated efforts by man to correct his interference with nature.

“We view the tamarisk as a pest,” Joseph Sigg, government relations director at the Arizona Farm Bureau, told The New York Times. “Water is an expensive input, and to the extent that we can lower it, the beetle can help.”

But the problem has not been solved, according to scientists who point out tamarisks or other trees will replace those fallen. In the meantime, bird species will be hurt by the tree losses, while the beetles will just go on eating whatever they can find.

“It’s one of the paradoxes of the tamarisk: There are worse alternatives,” Kelly Burke, executive director of the Grand Canyon Wildlands Council, told the newspaper. “Usually at the core of it is a simplistic equation that public officials and community leaders get in their head.”