For the first time in more than three months, visitors were walking along the trails at Seneca Park Zoo on Friday morning.
The zoo opened only for members. The public will be welcomed back on Sunday.
To limit overcrowding, visitors have to make online reservations, and 125 people will be allowed through the gate every half-hour. Acting zoo director David Hamilton said Friday's schedule was sold out, with 1,625 zoo members registering for tickets.
Once inside, everyone over the age of 2 is required to wear a mask and follow a one-way path through the exhibits.
Hamilton said some species of animals, including lions, snow leopards, otters, red pandas, and giraffes, are susceptible to COVID-19.
"We're not concerned that the visitors, if they're following all the rules and everything, that they would have any impact on the animals," he explained, "but we want to keep our keepers safe, because they're the ones who have to take care of the animals."
Hamilton said it will be an adjustment for the animals, and some of them may be a bit skittish after seeing only their keepers for several months.
"Our gray wolves have been very interested in people going by the exhibit," he said. "Since there have been fewer sounds in the neighborhood, they're able to hear sounds farther away and they've been howling more."
Certain buildings, such as the animal hospital and the Center for Biodiversity Exploration, are closed.
Reservations can be made at senecaparkzoo.org.