World Giraffe Day landed on 21 June when the Chicago Zoological Society (CZS) in Brookfield, Ill., announced that its animal care and veterinary staff would soon be on baby watch with the expectant birth of a reticulated giraffe at the Brookfield Zoo.

Arnieta, the 16-year-old mother, is due to deliver sometime between mid-July and late August. Since learning of her pregnancy last summer, Zoo veterinarians and animal care staff have been making every effort to help ensure Arnieta is successful in maintaining this pregnancy and delivering a healthy calf.

Arnieta was paired with Ato, who arrived at Brookfield Zoo in 2017 when he was nearly two years old. His arrival was based on a recommendation from the Association of Zoos and Aquariums’ Species Survival Plan, which is a cooperative population management program for select species in accredited North American zoos and aquariums. After waiting a few years until Ato reached sexual maturity, Arnieta conceived but experienced miscarriages in 2020 and 2021, both in the first trimester.

Following the miscarriage in 2021, Chicago Zoological Society staff began working with reproductive experts at Omaha’s Henry Doorly Zoo and Aquarium in Omaha, Neb., to monitor and evaluate Arnieta’s urine hormones to identify if she was cycling normally. Test results confirmed she could become pregnant.

Then, in July 2022, animal care staff began seeing signs that Arnieta might be pregnant, and urine samples from the hopefully expectant mom were once again sent to Ohama’s Henry Doorly Zoo and Aquarium, where Dr. Monica Stoops, director of reproductive sciences, and her team reported a positive pregnancy test the following month. The two facilities collaborated and borrowed knowledge from both animal and human medicine to create an innovative medical plan based on the understanding that Arnieta’s previous pregnancy losses may have been related to a lack of hormone production and/or potentially an infection.

“Our team at Omaha’s Henry Doorly Zoo and Aquarium is honored to have collaborated with Brookfield Zoo on this special partnership to support Arnieta in a healthy pregnancy,” said Dr. Stoops. “It’s through collaborations like these that veterinary teams from across the country are able to learn, share, and advance zoo science together, and we’re cheering for Arnieta and her calf from here in Omaha.”

Arnieta’s care, along with the supportive veterinary interventions, included training Arnieta for voluntary blood and urine collection, have been key to monitoring her pregnancy over the last several months. The staff is eager for a healthy mother and calf but prepared for every outcome.

Dr. Copper Aitken-Palmer, senior staff veterinarian for the Chicago Zoological Society and vice chair for the AZA’s Reproduction and Endocrine Scientific Advisory Group said, “Every birth/hatch at the Zoo is a very big deal and includes a lengthy birth plan with prepartum and postpartum considerations. Arnieta’s birth plan is no exception. Similar to human assisted reproduction, there are potential risks, so Arnieta’s plan included specific guidelines to ensure she gives birth on time and in a manner similar to giraffes in the wild.”

As her due date approaches, Arnieta will be separated from the other giraffes at Brookfield Zoo and provided with a private birthing stall and outdoor area. During this time, she will still have visual access to the rest of the herd and will be under 24/7 supervision by the animal care staff.

Dr. Mike Adkesson, president and chief executive officer of the Chicago Zoological Society and director of Brookfield Zoo said, “We are proud of the collaborative efforts our dedicated teams both here at Brookfield Zoo and at Omaha’s Henry Doorly Zoo and Aquarium have done to help Arnieta sustain this important pregnancy. Hopefully, the knowledge learned from her case will be useful in assisting other zoological experts in providing infertility care to not only giraffes but other species that may have complications during pregnancies.”

In 2018, the reticulated giraffe’s status was listed as endangered by the International Union for Conservation of Nature and Natural Resources (IUCN). The Giraffe Conservation Foundation (GCF) estimates that only about 16,000 individuals remain in their native habitat. Through AZA’s SAFE: Saving Animals From Extinction program, accredited zoos and their partners are working collectively to help save giraffes through education, scientific study, fieldwork, public awareness, and action. As efforts continue to ensure a growing giraffe population, Brookfield Zoo is committed to advancing how zoological experts can expand prenatal care for the species. 

Photos Credit: Jim Schultz, © Chicago Zoological Society - Brookfield Zoo