Close to 2,000 people visited the Singapore Zoo yesterday, the first day of the reopening of the zoo, Jurong Bird Park and the River Safari to the public.

The three wildlife parks were closed for nearly three months from the start of the circuit breaker in April and first reopened their doors to members only from Friday. The Night Safari will remain closed for the time being.

Each park can host up to 25 per cent of its capacity at any one time, and all visitors must buy tickets online, as well as book their time of entry, before their visit.

The parks are also using technology to monitor the number of visitors in real time and will trial systems that track crowd density, said a spokesman for Wildlife Reserves Singapore, which runs the parks.

Yesterday, a steady stream of families, couples and the elderly entered the zoo at 9.45am when the media arrived, and by 10.15am, there were 897 visitors. WRS did not reveal visitor numbers for Jurong Bird Park and the River Safari.

At a quarter of its capacity, each park can hold between 1,000 and 2,250 visitors.

As yesterday was the Youth Day school holiday, many visitors to the zoo were families with children in tow.

"With fewer people in the zoo, we were able to get closer to the exhibits, take better pictures and take our time at each exhibit," said Ms Jayne Oh, 38, a freelancer in accounting, who visited the zoo with her colleague.

To prevent crowding in the parks, features and activities such as tram rides and animal presentations are temporarily suspended, while the water play area in Rainforest KidzWorld is closed. Visitors have to book online to participate in animal feeding sessions.

The absence of trams was an inconvenience for some families with young children and the elderly.

"My mum is 62, so walking long distances can be difficult for her. It was also difficult for my seven-year-old daughter," said Ms Jamie Joseph, 35, a therapist.

Dr Yi Sangmin, 39, who used to visit the zoo with his family every month, said: "This time, we could visit only a portion of the zoo, as it is difficult to see everything without the trams.

"Every time we visited the zoo, we would ride the tram and enjoy one or two shows. That's something we missed today," added Dr Yi, a dermatologist, who was again there with his family.

Safety measures in the parks include self-disinfecting coating on frequently touched surfaces and floor markers for safe distancing at the exhibits.

A few visitors said they wished there were more staff at air-conditioned exhibits, as these places attract crowds that may compromise safe distancing rules.

A visitor who wanted to be known only as Ms Hong, 40, said: "People were not really standing on the designated floor markers in the kangaroo exhibit, and there was a small crowd.

"It would be great if there was someone at the exhibit to make sure visitors respect social distancing," she added.