The last capybara at the Santa Barbara Zoo was euthanized Friday, about three months after being diagnosed with a rare form of blood cancer.  

The 4-year-old capybara, Antonio, who was described as “gentle” and “curious,” had been undergoing chemotherapeutic treatment for his blood cancer, advanced multiple myeloma, according to zoo officials. 

Antonio’s condition showed “positive signs” of improvement during the past couple of months, zoo officials said, but in the last few days, he saw “significant decline.”

“With progressive limb weakness severely affecting his quality of life, it was decided that humane euthanasia was the best option for the ailing capybara,” Santa Barbara Zoo officials said. 

Zoo officials announced Antonio’s death in an online statement, and about three months after the zoo’s other capybara, 8-year-old Poppy, was euthanized after specialist veterinarians found an “inoperable” mass in her throat. 

Antonio and Poppy were the Santa Barbara’s Zoo’s only two capybaras. They arrived on the South Coast in 2023 and 2019, respectively. 

“While we wished to spend many more sunny years in Santa Barbara with Antonio, we are hopeful that the information gathered through his diagnosis and treatment may be shared to help other capybaras in the future,” zoo officials said online.

Community members took to the online announcement of Antonio’s death to mourn the capybara and send messages of support to Santa Barbara Zoo staff.