Samba and her sister, Tango, arrived at the zoo on 16 March after being transferred from Suffolk, but both escaped the following day.
Tango was found close to the pair’s temporary enclosure at the zoo and was swiftly retrieved but her sibling – described as the “more adventurous” of the pair – has been at large ever since.
Marwell Wildlife added that Tango “has been enjoying the warmer weather, often seen relaxing in the sun and napping in her hay”.
She remains in her private habitat while work is completed on her new home at the zoo.
Capybaras are the world’s largest rodents.
They are herbivores and are not considered dangerous to people.
In the wild they have few natural predators in the UK, so it is thought the biggest risk to Samba is traffic.
Marwell Wildlife is asking anyone who believes they may have seen Samba to take a photo and get in contact using the methods listed on its website, external.