Season 4

Four rare and mysterious tenrecs arrive at the zoo. Endangered eastern black rhino Kitani is due to give birth. And jewel wasp Ripley searches for a cockroach to turn into a zombie egg incubator.

Red panda Jung is losing weight and no one knows why. Mandrill Ludo gets over-friendly with his dad's girlfriend when his dad's at the vet's. Plus: tigers, and penguins.

Pygmy marmoset Audrey has to carry her babies everywhere. Andean bear cub Madidi embarks on an adventure into a neighbouring paddock. Plus: young elephants and baby hyraxes.

The chimps have been brandishing a large stick; keeper Niall tries to get it back. Male onager Holmes chases every female in sight - including the camel next door - during mating season.

Chester's bachelor pad of lemurs is about to be in for a shock with a dominant female on her way; a novice zebra starts to make a play for power, which isn't to top zebra Florence's liking; the keepers are desperate to breed Javan green magpies.

The keepers are busy making gifts for the animals but there's chaos when the chimps seek out their parcels. Will dwarf mongooses Cooper and Mini have new babies before Christmas? Plus rhinos and ants.

Sloth Tina has been giving her partner Rico a hard time, but the keepers have a plan to bring them closer together. And three-legged chameleon Tripod goes speed-dating.

The tapirs move to a new home. Golden poison frog Pablo has lost interest in his partner Maria, so bad boy El Loco is brought in to shake things up. Baby porcupine Marion faces off the meerkat mob.

Sun bears Toni and Millie have relationship problems. Critically endangered eastern black rhino Zuri gives birth to baby Ike. Otter Annie has three new pups. And camel Shan-shan is unwell.

It is time for mouse deer Una to leave her parents and meet a mate of her own, but she is being shy around her future partner, Biani. Aardvark Koos gets romantic with his sister in this night-time special. Can underdog seahorse Seabiscuit grow the vital appendage he needs to attract a mate?