Zoo officials said the decorations were put in place by an outside vendor and are meant to depict ghosts with light-up faces swaying in the breeze, KMOV-TV, St. Louis, reported Wednesday.
However, zoo visitors said the figures looked like they had black faces when not lit up and appeared to depict lynchings.
"It was like a complete outrage to me. It was very hurtful," zoo visitor Chris Burchett said. "The picture appeared to be black people hanging from a rope."
Zoo officials said they have decided to take the "ghosts" down after complaints from patrons.
"We've looked at what we've seen in terms of photographs, we've discussed and we've made the decision that we'll take them down," said Wyndel Hill, vice president of internal relations.