TULSA, Oklahoma - To ensure a healthy habitat for an endangered species of bird, crews are working to rebuild a sandbar on the Arkansas River.

Interior Least Terns come to Oklahoma each year to nest, and the work being done on the west side of the downtown Tulsa skyline will help the bird nest in a safe spot.

“The more we can do to have it as a very desirable habitat, that's what we want to do,” said Tulsa’s U.S. Army Corps of Engineers CEO, Earl Groves.

Interior Least Terns build their nests and lay their eggs in the sand.

Groves said a barren island in the Arkansas River has always given the endangered birds a healthy habitat for raising their young, but the floods of 2015 washed that habitat away.

“There virtually was no nesting season for the birds,” he explained.

The Corps of Engineers, with the help of a Tulsa County construction crew, are working fast to bring back a desirable sandbar.

The Corps said the Least Terns will start nesting in about a month, so they wanted to get it rebuilt and ready as soon as possible.

Least Terns migrate from Mexico to nest in the U.S. The birds are federally protected, and Groves said it’s his agency’s duty to make sure the birds thrive while in Oklahoma.

“Once any species is backed up with good habitat, and they're raising plenty of young and their numbers continue to grow each year, you can call that a success story,” Groves said.

The Corps of Engineers didn't generate any water from Keystone Dam over the weekend or Monday so crews could rebuild the nesting habitat.