There is a Bennett’s wallaby joey in Kids Kingdom at the Pittsburgh Zoo & Aquarium, and the zoo cannot tell you exactly when he was born. Arlo was most likely born in late October 2025. Keepers found him during a pouch check in early November, by which time he had already been in the pouch for weeks.
That is not sloppy record keeping. It is what a marsupial birth looks like from the outside, and it is the most interesting thing about this animal.
Why nobody sees a wallaby being born
A wallaby’s gestation runs about 26 to 38 days. What emerges at the end of it is not a baby animal in any sense a person would recognize: it is embryonic, blind, its hind limbs barely formed. It has one working set of tools, its forelimbs, and it uses them to climb unaided from the birth canal into its mother’s pouch.
Everything else happens in there. The joey attaches to a teat and stays attached, and the milk it gets changes composition over months as its needs change. Its limbs, eyes and organs finish developing in the pouch rather than in the uterus.
The trade is an energetic one. A short pregnancy costs the mother very little. The expensive part, producing milk, happens afterward, in a pouch she can carry with her, which suits an animal living in a landscape where conditions can turn quickly. If the season goes bad, a wallaby has not already sunk months into a pregnancy.
The pouch is a piece of equipment
It is a fold of abdominal skin, and it opens forward, which keeps debris out as the mother moves. A band of muscle around the opening lets her seal it shut while hopping or swimming. She keeps it clean herself, using her snout and tongue to remove the joey’s waste. Warmth, protection and food supply in one structure, carried at speed.
Arlo’s mother, Ava, carried him for roughly the standard term. He first put his head out in mid-April 2026 and came fully out for the first time in mid-May, around six months after birth, which is typical. He still goes back in to nurse and to sleep, and young wallabies will dive back into the pouch when startled well after they have started spending their days outside it.
What species is he?
Bennett’s wallaby, also called the red-necked wallaby, which is the species the Pittsburgh Zoo keeps. They are native to the eastern coast of Australia. The IUCN Red List assesses them as Least Concern with a stable population, so this is not a conservation story, and it does not need to be one.
It is a story about an animal most visitors walk past, doing something genuinely strange. Arlo, Ava and the zoo’s other wallabies are in Kids Kingdom, which a lot of families reach at the point in the day when the children have stopped reading signs. Arlo arrived in the middle of a busy summer for the zoo: the day before it announced him, it named and debuted its four-month-old lion cub, Kiazi, which is the kind of animal families come for. Stop at the wallabies anyway. The one in front of you spent half a year finishing its development inside its mother’s skin, and it is now standing on the grass pretending that is normal.
Sources: Pittsburgh Zoo & Aquarium, Welcome to the World, Walla-baby, August 11, 2026, and the zoo’s earlier Wallaby Joey Announced, June 6, 2024, for the species kept in Kids Kingdom. Red List category from the IUCN Red List of Threatened Species, version 2026-1.
Quick answers
- When was the Pittsburgh Zoo's wallaby joey born?
Most likely in late October 2025. Keepers discovered Arlo during a pouch check in early November, which is how marsupial births are usually detected: the newborn climbs into the pouch unseen.
- How long does a wallaby joey stay in the pouch?
About six months. Arlo first put his head out in mid-April 2026 and emerged fully in mid-May. He still returns to the pouch to nurse and sleep, and young wallabies jump back in when startled.
- What species of wallaby does the Pittsburgh Zoo keep?
Bennett's wallaby, also called the red-necked wallaby, native to the eastern coast of Australia. The IUCN Red List assesses it as Least Concern with a stable population.
- How long is a wallaby pregnancy?
About 26 to 38 days. The newborn is embryonic, blind and barely formed, and climbs to the pouch using only its forelimbs. Its limbs, eyes and organs finish developing there rather than in the uterus.
