The Pittsburgh Zoo & Aquarium recently welcomed Arlo, a male wallaby joey, to Kids Kingdom. Arlo was most likely born in late October, as he was discovered during an early November pouch check of his mother, Ava.

A wallaby’s pouch is one of nature’s most remarkable nurseries! It provides wallabies with a unique advantage as they raise their young in the often-unpredictable Australian landscape. This living cradle shelters the tiny, underdeveloped joey as it continues to grow for months after birth, providing protection, warmth, and easy access to milk.

After a very short gestation period (about 26–38 days), the tiny, embryo-like newborn joey is extremely underdeveloped. The pouch acts as a mobile incubator providing a safe and warm environment as the joey develops. It also allows the mother wallaby to invest less energy in an internal pregnancy and more in the energy-intensive process of providing milk for the joey.

The pouch is a fold of the wallaby’s abdominal skin that opens forward, so debris is less likely to enter when the mother moves. A band of muscles around the opening allows the mother to seal the pouch shut while hopping or swimming to keep the joey safe. A wallaby mom must also keep her pouch clean, using her long snout and tongue to clean away the joey’s waste.

A wallaby joey’s journey begins with an initial climb from the birth canal to the pouch, using its well-developed forelimbs. During its first weeks in the pouch, the joey is blind and immobile as its limbs, eyes, and organs mature. It secures itself to one of its mother’s teats and is fueled by the nutrients in her milk, which evolve to meet the joey’s changing needs as it grows.

The joey remains in the pouch for about six months. Even after leaving the pouch, the young wallaby often jumps back in when startled. Arlo first poked his head out of Ava’s pouch in mid-April and fully emerged for the first time in mid-May. He still returns to the safety of the pouch to nurse and sleep.

Come visit Arlo, Ava, and all the Zoo’s wallaby residents at their home in Kids Kingdom on your next visit!