The routine inspection of the Mark Twain Memorial Bridge that was to have taken place this week has been put off until August.

Officials with MODOT say that, as crews were preparing to inspect the bridge Monday, they discovered a peregrine falcon nest in the bridge’s steel understructure.

There were three eggs in the nest and two falcons aggressively guarding the nest.

While peregrine falcons are not on the U.S. Fish and Wildlife Service’s endangered and threatened species list, they are considered endangered species in the state of Missouri.

MODOT was in contact with the World Predatory Bird Sanctuary in St. Louis to confirm the discovery of the falcons.

Peregrine falcons typically nest between February and August, so the inspection of the bridge has been postponed until after August 1st.