When it comes to names there are a number of options.
Newborns are often named by keepers but sometimes naming rights are sold off to donors, privileges might be given freely to volunteers or as an honour, or even by public naming polls. How they decide which animals will be named which way largely depends on the popularity of the baby. The animals most likely to generate the most interest usually go with public polls like gorillas, polar bears, tigers, orangs ect.
Often new arrivals from other zoos already have names when the arrive. If they don't goes back to the newborn policy. Kiko would be an example of that. Most of the animals at the zoo arrived already named. Occassionally names are changed but its rare because the animals already know their names and keepers need to maintain training.
Now how they choose to name animals can very even more.
At times they decide on a naming theme. Warthog Norm was born at the zoo and his litter was named entirely after Cheers characters, Woody, Norm, Lilth, Rebecca. Another time the warthog piglets were named Bacon, Sausage, Ham and Porkchop. Themes are popular with animals who have litters.
Then there is times when they go after names which originate from the area the animal is from. Orangs Budi, Kembali and Jingga have names from Indonesia. The gorillas have been given African names.
Sometimes animals are named after important donors, volunteers or staff. One of the tortoises is names Johnny B. after a retiring curator of reptiles.
Other times they like to pick names that begin with one of the parents initials. All gorilla babies are given names that start with their mothers names. Once they started that Josephine's babies were Jomo, Jabira, and Johari. Samantha had Sekali, Subira, Shalia and Sadiki. Ngozi has Nassir and Nneka. None were named after Charles. Not all species do that.
Toronto doesn't do it but some other zoos name all babies born in a given year using one letter to start all names. Could be the year of X... not likely.
And there are times its just random. The keepers just might think a certain name fits.
My favourite name of all time on a red river hog was Sir Pigglesworth. Cracks me up every time.
. I really don't know their theme with the African penguins, they get some pretty different names lol!