Philadelphia Zoo has made history with the birth of four critically endangered giant tortoise hatchlings. The zoo announced the exciting news this week, sharing that Mommy, a 100-year-old Western Santa Cruz Galapagos tortoise, became a mother for the first time alongside her partner Abrazzo.
This remarkable milestone comes nearly a century after Mommy arrived at the zoo in 1932, making her the oldest known first-time mother of her species. The births are part of the Association of Zoos and Aquariums’ breeding program, designed to boost the genetic diversity and survival of the Western Santa Cruz Galapagos tortoises.
These species face severe threats in the wild. Before these hatchlings, there were only 44 of their kind living in U.S. zoos.
The first of the 16 eggs hatched on February 27, 2025, with others quickly following. Weighing between 70 and 80 grams, the hatchlings are currently kept behind the scenes at Philadelphia Zoo’s Reptile and Amphibian House.
They are “eating and growing appropriately,” according to the zoo’s staff, and will be publicly introduced on April 23, 2025—the 93rd anniversary of Mommy’s arrival at the zoo.
The impact of this event goes beyond just zoo history. It offers hope for the survival of an endangered species whose population has been severely affected by habitat loss, invasive species, and human activities. Breeding programs like this are essential for maintaining genetic diversity within a population. It’s a challenging process, especially considering the tortoises’ long incubation period of four to eight months and the fact that many previous attempts to breed Mommy’s eggs were unsuccessful.
“This is a significant milestone in the history of Philadelphia Zoo, and we couldn’t be more excited to share this news with our city, region, and the world.”
said Dr. Jo-Elle Mogerman, the zoo’s president and CEO.
The zoo’s vice president of animal well-being and conservation, Rachel Metz, added, “We take great responsibility participating in the Galapagos tortoise species survival plan, and are thrilled for this successful pairing of Mommy and Abrazzo.”
Abrazzo, the father of the hatchlings, arrived at Philadelphia Zoo in 2020 after previously residing at Riverbanks Zoo and Garden in South Carolina. Although Abrazzo had previously fathered five tortoises, Mommy had never successfully hatched her eggs until now.
The success of their pairing represents a significant achievement in the broader effort to preserve these rare tortoises.
The Western Santa Cruz Galapagos tortoises are native to the Galapagos Islands in the Pacific Ocean. Of the 13 species that once roamed the islands, several have gone extinct. Those remaining face ongoing challenges due to limited genetic diversity and the harsh realities of their threatened habitats.
The Philadelphia Zoo’s breeding success adds a glimmer of hope for conservationists. The hatchlings serve as symbols of resilience and potential recovery.
“These hatchlings not only protect the species from extinction but serve as important ambassadors to inspire guests to save wildlife and wild places.”
said Rachel Metz.
As the public debut of these hatchlings approaches, all eyes are on the Philadelphia Zoo. Visitors will get the rare chance to witness a conservation milestone and connect with one of the world’s most endangered species. With Mommy’s age and Abrazzo’s breeding history, this successful pairing is a testament to perseverance and the critical role zoos play in species preservation.
But while the zoo celebrates, the question remains: Can efforts like these be enough to save such a fragile species from the brink of extinction? The story of Mommy and Abrazzo’s hatchlings may be just the beginning of a broader effort to secure a future for Western Santa Cruz Galapagos tortoises.