Endangered interior least terns and threatened piping plovers will have to make-do with existing sandbar nesting habitat on the Missouri River at least one more spring.

The U.S. Army Corps of Engineers has delayed its spring plans to start defoliating overgrown sandbars in the Garrison Reach to create more nesting space for the two struggling species.

The corps is in discussions with several tribes downriver, where it is planning similar sandbar work, thus delaying all work, Paul Johnston, a corps spokesman in Omaha, Neb., explained Monday.

"The need for additional sandbars has not gone away," he said.

Plans to spray a defoliant on overgrown sandbars will be pushed back about 70 days, Johnston explained, but the corps still has late summer plans to spray some islands where the river-dwelling birds aren't nesting.

Other sandbar work, such as backhoeing or dredging, remains on track for late summer, Johnston said.

Sen. Byron Dorgan, D-N.D., weighed in on the matter Monday, calling the project "sandbar bird hotels." The North Dakota Democrat vowed to use his position on the Senate Appropriations Committee to move the $83 million intended for the emergent sandbar habitat project to other projects that will meet water needs for North Dakota communities.

"People habitat has to take priority over bird habitat," he said, adding that he does favor protection for the birds.

The corps' project is intended to comply with one alternative of a biological opinion issued by the U.S. Fish and Wildlife Service, which oversees species, including the plovers and terns, that are protected under the Endangered Species Act.

The birds prefer mostly barren nesting sites as a means of protection from predators.

Sandbar work is planned along a stretch of the Missouri River from Fort Peck, Mont., to Ponca, Neb., and the plan has attracted criticism along this portion of the river.

Concerns raised include hazardous boating conditions, sandbar access, bank erosion, possible delta flooding and endangered municipal water supply intakes. Other species that either live in the river or use its sandbars also could be adversely affected, biologists say.

"There are only two ways to get (sandbars)," Johnston said. "Either Mother Nature has to have big flows for a long time, and she puts them where she wants, or we do mechanical work in places where the birds have nested before and not at the edge of intakes or marinas."

(Reach reporter Richard Hinton at 250-8256 or outdoors@bismarcktribune.net.)