It's National Ferret Day! 🐾 Black-footed ferrets were once the most endangered mammal in North America, with just 18 ferrets remaining in the wild in the early 1980’s. As the final attempt to save the species, these ferrets were brought into human care to establish a breeding and reintroduction program. Since 1992, black-footed ferrets have been bred at your Toronto Zoo, with the aim of preventing extinction. However, not all ferrets successfully breed in human care. Recently, researchers at your Toronto Zoo and the University of Toronto Mississauga conducted a study to investigate this variation in ferret breeding success. This study found that, compared to female ferrets that successfully gave birth, the females that did not reproduce had slightly reduced concentrations of the reproductive hormone, progesterone, and the stress-associated hormone, cortisol. The study also found that, compared to males that successfully fathered young, males that did not attempt to mate had reduc...