CHICAGO (CBS) —  A lot of people are eager to see the animals at Brookfield Zoo when it reopens. So many people tried to get advance tickets Friday that the zoo’s servers crashed.

Zoo members were invited to start reserving times tickets for their next visit through the zoo’s website, but just a few hours later a message appeared saying high demand overwhelmed their ticketing system.

Ticketing is now on hold while the zoo fixes the issues.

Brookfield Zoo opens to member July 1 and the general public July 8.