Happy Hollow mourns the loss of a critically endangered black and white ruffed lemur

August 6, 2021

Ala (right) and her twin Alina (left) at one month old

It is with a heavy heart that Happy Hollow shares the passing of Ala, one of the black and white ruffed lemur pups born this spring. She was 3 ½ months old. As part of the Ruffed Lemur Species Survival Plan (SSP), Ala and her twin Alina are critical members of this breeding program, helping to ensure the survival and strength of their species. Earlier this year we shared the story of their parents Vintana and Nify and our hope for another healthy lemur pup this spring. There was trepidation when an X-ray showed Vintana to be pregnant with twins, as her previous multi-pup pregnancies ended unsuccessfully, and then relief and excitement when she gave birth to two healthy pups. Happy Hollow staff and visitors quickly fell in love with the twins, watching them bound around their habitat, play with their siblings and parents, and learn how to be lemurs.  

Unfortunately, not all stories unfold as desired. On July 27, Ala was examined by one of Happy Hollow’s veterinarians after zookeepers noticed that she had a swollen knee, and she was treated with medication for pain and swelling. Since she was still very young and in need of her mother’s care, as well as the socialization of the group, Ala remained with her family in the black and white ruffed lemur habitat. Over a few days of treatment she showed signs of lethargy, which is common when on pain medication, but was observed eating and nursing normally. On the morning of Aug. 2, she was discovered on the ground away from her mother, cold, dehydrated and with severe diarrhea. Despite treatment by the vet, supportive care throughout the day, and emergency intervention, including CPR, she went into shock and passed away in Doc’s Critter Care.  

“The entire Happy Hollow team feels the pain of losing this especially precious endangered animal,” says Happy Hollow General Manager, Kiersten McCormick. “The animal care team performed admirably to facilitate Ala’s care in an emergency situation, and they are moving forward with incredible professionalism.”

Initial results from a necropsy (animal autopsy) performed on Aug. 4 were inconclusive and unfortunately did not shed any light on the cause of Ala’s ailment. Blood, fecal and tissue samples have been sent out for laboratory testing, which can take several weeks to produce final results. Any relevant findings will be shared with an update to this post. The rest of the black and white ruffed lemur group is being closely monitored for changes in behavior as well as signs of potential infection or ailment. So far, all appear healthy and normal. 

Although this news is heartbreaking, Happy Hollow takes pride in the level of animal care provided by our team on a daily basis. “Our thoughts and support are with the Happy Hollow team during this difficult time,” says Neil Rufino, Assistant Director of San Jose’s Department of Parks, Recreation and Neighborhood Services. “The zookeepers and entire animal care team provide a consistently high level of care for all of Happy Hollow’s animals, and their efforts make an important difference both for those animals and their counterparts in the wild.” 

Despite this setback, the Happy Hollow team remains committed to the Ruffed Lemur SSP and dedicated to the mission of connecting people to nature through play. They continue to provide excellent care to all of our animals who, like Ala, will inspire wonder and glee in visitors who are lucky enough to see them. Her sister Alina is doing well and can be seen in the black and white ruffed lemur habitat along with the rest of the family.