Part of the delay was to allow United to have a replacement aircraft prepared to take the passengers to their destination while the original Flight 1178 was rid of the arachnids and checked for other possible pests, the Des Moines Register reported Wednesday.

"It is an unusual situation to find ticks on the plane, and we regret any inconvenience this might have caused our customers," United spokeswoman Robin Urbanski said.

Urbanski said the remainder of the delay was due to severe thunderstorms.

United said it has not yet determined how the ticks managed to get aboard the plane.