How Do You Know if There’s a Joey in the Pouch?

Three new joeys live in the kangaroo yard this year and all of them are mature enough to spend time out of the pouch. We can hardly believe they’re all over eight months old! But with all that time spent in the pouch, we wanted to know how early zoo keepers knew the mama kangaroos had joeys…and how they could tell!

Kangaroos are pregnant for only a month before giving birth to their jelly bean-sized baby (yay for ten-day trimesters), and zoo keepers may not even realize that a kangaroo is pregnant. Immediately after birth, the little one climbs all by itself into the pouch. This takes about 10 minutes. Sometimes zoo keepers witness the tiny bab’s ascent, and sometimes they don’t; so they rely on mom’s behaviors to help clue them in on the pregnancy.

Zoo keeper Marian Powers says it’s difficult to tell when a kangaroo is pregnant, so keepers watch for changes in behavior. “We record all observed breeding behavior, so we have some idea of things that may be happening,” says Powers. “We might also notice mom leaning and preparing her pouch. When the pouch is empty, it develops a waxy coating to keep the skin protected. When mom is getting ready to give birth, she sticks her head in her pouch and begins cleaning that wax off.”

Once the baby is in the pouch it latches on to a teat and stays all safe and snuggled inside for the next six months. During this time, the joey grows and begins moving around. Sometimes it’s during this pouch-only phase of growth that zoo keepers can confirm birth. After about six months a little foot or tail finds its way out, and everyone knows there’s a baby on board.

Zoo keepers wait for the opportunity to confirm a new joey, but it can take time. “The first sighting of a toe or the tip of a tail or nose is an exciting moment. Joey watch requires a lot of patience!” says Powers.

Eventually the joey will leave the pouch for short periods of time. As it grows stronger and gains independence it leaves the pouch for longer durations and begins hopping like the adult kangaroos. But for the first half year of life, a joey’s entire world is a safe, snug little nursery attached to mom.

Animal babies are sponsored by Lutheran Children’s Hospital.

Click on the photos to enlarge: