Bluebirds, eco-indicators point to healthier Oak Openings

1/24/2004

Eastern bluebirds like what s happening out at the Oak Openings.

Jennifer Finfera, a naturalist for Toledo Area Metroparks, told a crowd gathered for a research forum that not only are bluebird numbers on the increase, but long-term monitoring of cavity-nesting birds tells why.

Ms. Finfera was one of a group of speakers to review research taking place in the Oak Openings region in western Lucas County.

The sandy soil of this ancient beach ridge is home to more threatened and endangered species of birds, insects, amphibians, reptiles, and plants than anywhere in Ohio.

Yesterday s gathering at the Wildwood Preserve Metropark revealed the status of many of those species.

Bluebirds are one of the winners.

“The number of birds fledged per box increased dramatically, Ms. Finfera said.

From 1996 to 1998, more than five baby birds left every nest box - an all-time high. Since then, fledgling rates have remained nearly as high.

At the same time, wren numbers fell.

One factor behind the bluebird prosperity was a change in home styles.

In 1997, naturalists swapped boxy birdhouses for stylish models with sloping roofs. The new homes stand atop not wooden posts but PVC piping. A wire-mesh predator guard surrounds each entry.

But these predator-prevention measures are only part of the changes helping to bolster bluebird numbers, Ms. Finfera said.

At the same time, Metroparks land managers increased the number of prairie acres burned each year, clearing away much accumulated scrub.

They also took down trees in 200 acres of savanna, allowing the sunlight to reach the prairie floor.

The result? Perfect bluebird territory.

Although bluebirds and wrens eat the same food and like the same homes, wrens like brush and scrub-covered ground. Bluebirds crave the wide-open spaces.

Another sign of health in the Oak Openings region is the return of the prairie gentian, a dazzling blue flower last seen here in the 1960s. The plant is on the Ohio Endangered Species list.

Metropark naturalist Bob Jacksy said a volunteer found the flower and brought a picture of it to the visitors center for identification.

“It s one of those things that, when you see it, you get goosebumps and your heart starts beating a little faster,” Mr. Jacksy said.

A single plant with four flowers was found blooming in late September.

Another signature of ecosystem health is an abundance of frogs, reported Kim High, a park naturalist.

Frog surveys began in the Oak Openings region in 1994. The surveys show that the spring peeper is the most abundant frog.

Volunteers keep track of frogs by listening for their mating songs along specific pathways. Spring peeper calls make up 73 percent of the choir, followed by western chorus frogs, at 20 percent, wood frogs at 3 percent, and gray tree frogs at 1 percent.

The presence of the wood frog is particularly important, since Mick Micacchion of the Ohio Environmental Protection Agency said that wood frogs are one sign of a high-quality wetland.

Moth monitoring in the Oak Openings led to the discovery of what might be a new species of moth, said Eric Metzler of the Ohio Lepidopterist Society.

Northwest Ohio and southern Ohio are both home to a species called the buck moth.

But further study reveals that, although the two moths appear identical, they are different species.

The two rely on different food plants, and, when offered the opportunity, would not mate. Mating specificity is one of the classic species distinctions.