One of the dolphins at the Minnesota Zoo is pregnant, and another is acting like she is.

That's prompted the zoo in Apple Valley to temporarily cancel its popular dolphin show.

The zoo brought in two female dolphins in January, hoping to breed them with the zoo's only male dolphin, Semo.

One of the females, named Allie, is now pregnant and due next spring. The other female, April, is not pregnant but is seemingly acting as though she is.

Kevin Willis, director of the zoo's biological programs, says they're are trying to figure out why April is showing signs of pregnancy, when she's not. She's also been eating less and is undergoing diagnostic testing by veterinary staff at the University of Minnesota.

Willis says it's "not an easy decision,'' but the zoo decided to "just let those animals have a break.''