Critically Endangered Monkey Gives Birth After Foot Surgery
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- Masaya, a 15-year-old critically endangered roloway monkey at Chester Zoo, gave birth to her third daughter Lagertha months after a golf-ball-sized mass was removed from her foot in a complex operation that saved all but one of her toes.
- Chester Zoo vets partnered with surgeons from the University of Liverpool's Small Animal Teaching Hospital for the procedure, which Rachel Burrow described as the last chance to save Masaya's foot before amputation — a surgery with no prior precedent in roloway monkeys.
- Zoe Edwards, primate keeper at Chester Zoo, said Masaya is now parenting "magnificently" and that the healed foot was critical, since an amputation would have raised serious questions about whether she could hold her offspring or maintain normal behaviors.
- Chester Zoo is one of only two UK facilities housing roloway monkeys, and Masaya is considered highly significant to the European Endangered Species Programme because only a few breeding females remain in European zoos.
- Roloway monkeys number fewer than 2,000 in the wild, restricted to Ghana and the Ivory Coast, where they face habitat loss and poaching, per the IUCN.
- Masaya's recurring foot problems had stumped vets with X-rays, ultrasounds, and biopsies since she arrived at the zoo in 2023; a likely persistent abscess, possibly from an old thorn injury, was eventually identified via CT scan in 2025.
Why it matters: Each surviving breeding roloway female carries outsized weight for a species with fewer than 2,000 animals left in the wild and only a handful of breeding females in European zoos. Saving Masaya's foot preserved not just her own mobility but her ability to hold and care for offspring — a direct, concrete contribution to the European Endangered Species Programme's genetic reservoir.
