Getting Ready for Baby Sloth #2

Our Keepers and Vets Have Been Hard at Work to Ensure a Smooth Arrival for Baby Ruth’s Sibling

By Stacy Johnson, Zookeeper

By now you’ve probably heard the news that Baby Ruth, our almost-one-year-old Linne’s two-toed sloth, is getting a baby brother or sister! Now we’re sharing an inside look at how our animal care and veterinary medical teams work tirelessly—and verrrry—patiently to bring sloth babies into the world. Read on to learn how we trained Charlotte to participate in exams and ultrasounds, and what we’re doing to get the sloths and their habitat ready for baby #2:

The Perfect Pair

Charlotte, our 23-year-old female sloth, has been a mom several times before at other zoos, which is why she became a recommended breeding mate to Elliot, our 27-year-old male sloth. Charlotte arrived at Denver Zoo in 2015 with the hopes of being a good match for Elliot, who has been here since 1996. He had previous mates, but with no breeding success. Fortunately, Charlotte and Elliot were smitten with each other from the get-go when they were introduced in Bird World three years ago. Sloths are famously slow, even when it comes to forming bonds and territories. That’s why, despite an instant connection, it took a few years for Charlotte and Elliot to mate successfully!

Tick-Tock, Tick-Tock

In the meantime, keepers spent six months working with Charlotte on training techniques to get her comfortable with medical exams and being touched (contrary to popular belief, it is not natural for a sloth to enjoy being touched). We knew it was going to be important to monitor Charlotte if she ever became pregnant, particularly when it came to getting visuals on the baby, but we never imagined that Charlotte would become such a rock star with training! Not only did she allow keepers to perform tactile training, but she also she allowed veterinary staff to perform ultrasound exams. Her very first ultrasound was a success. This enabled us to monitor her throughout the rest of her pregnancy with Baby Ruth and now with baby #2!

Welcome, Baby Ruth!

On January 28, 2018, we welcomed Baby Ruth, the Zoo’s first successful sloth birth and Elliot’s first offspring! A few weeks later, we used a DNA sample from her hair to determine her sex (as sloths do not have external genitalia), and announced it with the help of a sloth super-fan from Children’s Hospital Colorado. Charlotte and Elliot took to parenting better than we could have hoped—Elliot played his sloth dad role perfectly by keeping to himself, and Charlotte responded to training less than 24 hours after giving birth, which allowed us to conduct a modified exam on both her and Baby Ruth. The last year has been full of amazing firsts, and we’ve loved watching Baby Ruth grow up. She is just now starting to spend time on her own, just in time for her sibling to arrive this winter!

Preparations are Underway

Baby Ruth will stay at the Zoo for at least another year before she finds another recommended home. In the meantime, we hope to manage our four sloths as a family group in Bird World. We’ve set up a camera system so we can watch their behaviors overnight (they’re a nocturnal species) to see how they’re getting along with each other, and have a Plan B ready to go in case we need to remove Baby Ruth or Elliot for short periods of time while Charlotte gets adjusted with the new baby.

We’ll continue to use the sloths’ behavior to determine their needs and have already made some adjustments to their habitats so they have more room to roam and move away from one another (sloths are generally solitary as adults). Our priority is to make them comfortable with the new setup now so they know exactly where to go when the baby arrives.

To be honest, we don’t know what to expect with our second baby sloth, but we are prepared for whatever may come our way. Be sure to follow us on Facebook, Twitter and Instagram, and subscribe to the Zoo on YouTube so you can be among the first to get the latest baby sloth updates!