Starting Saturday, the Los Angeles Zoo will again be requiring advanced online reservations to enter, officials announced Thursday.

The reservations require guests to select only the day on which they will visit, and while timed entries are not in effect, daily capacity will be limited, officials explained.

Walk-up ticket sales are not recommended and will no longer be guaranteed.

Reservations can be made online, and tickets will be sent to the email address provided at the time of booking. The last entry to the zoo is at 3:45 p.m. daily.

The new system is to ensure “the safety of our animals, guests, and staff,” officials said in announcing the policy.

All visitors 12 and older are already required to provide proof of full COVID-19 vaccination or a negative test taken within 72 hours of entering the zoo. Additionally, face coverings are required for all visitors 2 and older at indoor and enclosed settings, including the amphibians, invertebrates and reptiles exhibit, food service locations, restrooms, and the shuttle. Guests who are not fully vaccinated are recommended to wear face coverings outside as well.

For more information about tickets, visit the zoo’s “know before you go” page.

The zoo has made changes since first reopening to the public in August 2020, and many exhibits, activities and services remain closed.

Another coronavirus wave forced the closure of the zoo that December, and officials implemented a reservation system once it reopened in February 2021. It is unclear, however, when that reservation system was momentarily discontinued.