Woodpeckers and Emerald Ash Borer

Woodpecker Population Rising in Detroit

From Nature World News

By Staff Reporter

Aug 12, 2013 08:16 AM EDT

A male Red-bellied Woodpecker (Melanerpes carolinus).
Population of Red-bellied Woodpecker increased after arrival of emerald ash borer. (Photo : Ken Thomas/ wikimedia creative commons ) 

A new study has found that the population of at least two species of woodpeckers is rising in Detroit.

In the study, researchers from Cornell University and the U.S. Forest Service looked at population of woodpeckers in Detroit and a region that's 62 miles away from the city, reported the Detroit Free Press. They also looked at the bird population in five other Midwestern cities.

Researchers found a higher population of red-bellied woodpeckers and white-breasted nuthatches in Detroit. They claim that the population was highest in cities that had a severe emerald ash borer problem. The Emerald Ash Borer (EAB) is an invasive beetle species whose larvae feed on the inner bark of native ash trees, eventually killing the trees in a few years.

"One of the easiest ways to find an infested tree when you're out in the field is to find a tree that's been heavily attacked by woodpeckers. They destroy the bark of the tree, preying on the emerald ash borers. It almost looks like the tree exploded," said Andrew Liebhold, an insect scientist for the U.S. Forest Service and co-author of the study, according to Detroit Free Press.

"The emerald ash borer has been massively destructive because most North American ash trees have little or no defense against it," Liebhold said in a news release. "We can take heart that native woodpecker species are clearly figuring out that EAB is edible, and this new and widely abundant food source appears to be enhancing their reproduction."

However, the team also found that the population of other species of woodpeckers- downy and hairy woodpeckers began declining after the arrival of Emerald Ash Borers. EAB was first discovered in southeastern Michigan near Detroit in the summer of 2002.

The decline of certain woodpecker species could be because the birds faced competition from other species or that they were slow to adapt to the latest addition in their diet, according to Walt Koenig, co-author of the study from Cornell. "Some species really aren't very good at taking up novel food items," he told Detroit Free Press.

The study is published in the journal Biological Invasions.