PREVIEW

Over the holiday season staff at Toronto Zoo received one of the most remarkable gifts of all - a white rhino calf!
On the morning of Thursday, 28 December 2023, mum Sabi gave birth to her first calf.


While every rhino pregnancy is exciting, Sabi’s was especially so. Following her arrival in Toronto in 2012, hormone monitoring performed by the zoo's Reproductive Science team identified that Sabi exhibited "long" estrus cycles (~70 days in length, compared to the typical ~30 days of fertile females), which have made conception a significant challenge for her.


Following continual adjustments in daily care and diet, Sabi’s behaviour in spring 2022 suggested that her hormonal cycles had switched from the long cycles to the typical cycle length. The likelihood of successfully conceiving for the first time drops with age in many species, including white rhinos, and Zoo staff were keenly aware of this with Sabi.


Toronto Zoo Wildlife Care and Reproductive Science teams were thrilled that the breeding introductions with white rhino male Tom in summer 2022 were successful. This is the second calf sired by the 15-year-old rhino. His first calf, Theo, was born December 24, 2017, and left Toronto in late 2021.


"As we've learned in many species, successful reproduction is dependent on optimal animal health and well-being” says Dr. Gabriela Mastromonaco, Senior Director of Wildlife Science, Toronto Zoo. “With fertility challenges being a significant concern for conservation breeding programs, your Toronto Zoo focuses on a holistic approach to well-being that brings together our wildlife care and science teams to develop treatment plans that support individual animal needs. We are excited to see our teams' efforts rewarded with the new addition to our rhino family."
Sabi’s calf came into the world following a few hours of labour. It was around midnight when Sabi’s Wildlife Care team began noticing her walking and rolling around. When keepers checked on her in the early hours of the morning, more fluid had been discharged and her water officially broke, culminating with a successful delivery at 7:58am.


A white rhino’s gestation period lasts approximately 16 months - meaning staff had a longtime to wait caring for Sabi throughout her pregnancy.


“It’s amazing to be working with such a passionate and dedicated team and having the opportunity to share Sabi’s story” says Dolf DeJong, CEO, Toronto Zoo. “Staff have been working overnight shifts to make sure someone was always with Sabi through the later stages of her pregnancy. They’ve been “baby-proofing” the habitat and the veterinarian team have been keeping a very close eye on her, particularly over the last few months to ensure we did everything possible to help bring a healthy calf into the world. We’ll be giving Sabi and her calf lots of space to bond, and we know our community will be here showing their support when the baby is viewable, likely this spring.”
White rhinos in the wild are listed as Near Threatened on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species. There are fewer than 16,000 left in the wild, with numbers currently declining due to habitat loss and the continued increase in poaching for their horn for the illegal wildlife trade.


In honour of this significant birth, the Toronto Zoo Wildlife Conservancy has created the Wilding Rhino Conservation Fund to support organizations like the International Rhino Foundation and the critical work organisations like these do to protect wild rhino populations.