Ntondo the silverback gorilla gets diagnosed with glaucoma; Malayan tiger cubs; endangered maleos.

A tomistoma, a freshwater crocodilian, stops laying eggs and keepers scramble to treat her.

The future of the American Bison depends on a high-stakes race across the country; reptile staff have their hands full with a diamond rattlesnake that needs to be medicated orally; a pair of cheetahs are trained to walk the zoo grounds.

Huge male sea lion is in rut, and the younger males must be moved before he becomes territorial.

Birth of a little blue penguin causes a sensation; something is wrong with Snowball, a snow leopard.

To help love bloom between two kiwis, zoo staff build an elaborate hut into which they introduce a pair of potential mates; when a King Cobra arrives at the zoo, keepers trains him to move from the exhibit to a holding pen.