ST. PAUL, Minn. - Special radars are going up on bridges along the Mississippi, to monitor not traffic -- but birds.

It's a first of its kind study to look at the impact bridges have on migrating birds.

The radars will be put in three places: the Wakota Bridge, the Washington Avenue Bridge and the Hastings Bridge.

The Mississippi River is a path of migration for millions of birds each year. That's why work is beginning along its route, to determine just how, if at all, man-made structures have an effect on them.

"Getting data on the effect that bridges might or might not have is really difficult," says Biologist Alan Clark from Fordham University. "So this is really a first-of-a-kind study."

Clark is collaborating with the National Park Service installing radar and sound equipment on two bridges in the Twin Cities: the Washington Bridge, which connects the University of Minnesota's East and West Bank; the Wakota Bridge in St. Paul; and the 61 bridge in Hastings, which is the first of the three locations using ground radar.

"We hope to have some answers about whether this bridge or bridges like it are a problem for migrating birds, and if they are, then maybe there are things we can do," Clark says.

Researchers say bird strikes on bridges likely happen by the hundreds of thousands each year. But since they're over water, most of the bodies or any evidence of a strike washes away.

"Nothing has been done on bridges, as far as we know, in the entire world," says Nancy Duncan from the National Park Service. "So there has been huge interest in this study. We've gotten requests from, like, the New York DOT, and California called."

Part of the Hastings Bridge construction budget included money to fund bird mitigation in hopes of finding answers to make smarter future bridge projects a reality.

"Maybe future bridges can be designed to reduce the impacts that they might have on birds," Clark says.