Gorilla heart health possible thanks to incredible bond with animal keepers

Posted by Elizabeth Bacher, Communications

Editor's note: Special thanks to gorilla keepers Kate Gordon and Stephanie Payne. It is because of their hard work and close, trusting relationships with the gorillas that we can share stories like this with you.

The relationships that our animal keepers have developed with gorillas, like Olympia and Nadaya seen here, have allowed our care team to more closely monitor their heart health. Photo: Jeremy Dwyer-Lindgren/Woodland Park Zoo

Heart health is important for us all, especially as we age. This is also true for gorillas and other apes living in human care. They are susceptible to health problems related to cardiovascular disease—also known as CVD or more simply “heart disease”—just as we are.

Formally established in 2010, the Great Ape Heart Project (GAHP) addresses the critical need to track and understand heart disease in great apes—including gorillas, chimpanzees, orangutans and bonobos that live in human care. Just like in humans, cardiovascular disease can lead to health declines and even death for these primates—especially as they age. The goal of GAHP is to establish uniform heart disease prevention strategies as well as state-of-the-art diagnosis tools and treatment plans that can be shared with partner zoos and veterinary schools/hospitals all over the world. Another important element is to establish baseline heart readings of apes when they are awake—without any sedation. The readings taken during a sedated exam can be informative but are not as accurate as readings taken during a normal, awake state.

Kwame seems to enjoy one-on-one time with the gorilla keepers. He participates in training sessions to monitor his health, plus he gets to enjoy some of his favorite treats in a relaxed setting. Photo: Jeremy Dwyer-Lindgren/Woodland Park Zoo

One of the most basic and least invasive ways to monitor heart health is through the use of an electrocardiogram—also known as an EKG—which uses electrical signals through sensors next to the skin to record the heartbeat. In years past, EKGs needed to be done at medical offices or hospitals. But today the use of apps on personal devices, including smartphones and watches, allows people to participate in their own care by monitoring their heart health from home.

Some zoos are now using KardiaMobile brand sensors—the same ones people can use—to track cardiac health in great apes. In addition to being readily available, they are also relatively inexpensive and can be used with any phone or device that has Wi-Fi or a Bluetooth connection—a great choice for animal care staff wanting to monitor the heart health of the primates in their care. But none of this is possible without first focusing on the relationship and bonds of trust that exist between the gorillas and the gorilla keepers who know them so well.

Sweet and gentle Olympia, one of the females in Nadaya's family group, seems to enjoy training sessions (and the snacks that come with them) too. Photo: Jeremy Dwyer-Lindgren/Woodland Park Zoo

There are currently 11 gorillas living at Woodland Park Zoo, in two separate family groups, each led by one of our two silverbacks (the adult male family leaders) Kwame and Nadaya. Every day, our amazing gorilla keepers carve out time to work with the gorillas in voluntary, one-on-one positive-reinforcement (think favorite treats!) training sessions, through protective mesh, that build trust. Many of our keepers have been working with these gorillas for years and even decades, so the relationships between them are longstanding and strong.

Before sessions could begin with the KardiaMobile equipment, modifications were needed in the behind-the scenes spaces to make sure the sensors could be properly placed for both the gorillas and the keepers. And since it is normal and natural for gorillas to show caution around new things, the keepers made sure there was time to desensitize them to the equipment, so they’d be comfortable with it. All of this takes time, patience and trust.

Cincinnati Zoo is one of the partner institutions for the Great Ape Heart Project. Here you can see one of their sessions where gorilla Tulivu's fingers were small enough to fit on the sensor pad. Photo: Courtesy of Cincinnati Zoo

The sessions began with establishing “touch” (with fingers), “sit” and “chest” behaviors (for a makeshift “wand” with an attached sensor to touch their chest). Then desensitizing to the sensor platform, the sensor itself and the phone. Each new item that was unfamiliar to the gorillas required time to allow them to get comfortable with it. They also needed to be comfortable with a keeper lightly pressing on their “pointer” fingers to increase pressure and improve the electrical signal. The keepers wore gloves during these sessions to make sure their own conductivity did not interfere with the gorilla’s.

One of silverback Nadaya’s favorite treats is grapes. He has always seemed to enjoy the one-on-one keeper attention (and the grapes) that go along with training time. So that was his go-to snack for cooperating in these sessions. Nadaya was great at placing his fingers where they needed to be on the 2-lead sensor, but they were a little too big for the small touch pad which was designed for human fingers. Also, it was difficult to get him to hold his fingers still with the proper amount of pressure in place long enough to get a proper 30 second reading. This is where the chest sensor came into play. It worked for Nadaya, our other silverback Kwame, and several other gorillas!

A chest sensor works better for some of our larger gorillas like Kwame. These training sessions are completely voluntary and the gorillas can stay relaxed and enjoy some treats while EKG readings are taken. Photo: Jeremy Dwyer-Lindgren/Woodland Park Zoo

The switch to a chest presentation with a 6-lead sensor using Bluetooth solved the “fidgety fingers” problem. EKG readings from Nadaya, Kwame and some of the adult females could now be shared with our veterinary staff to use and review as needed.

Our veterinarians say Kwame's sinus rhythm is normal and healthy. We are so fortunate that the trusting relationships between our animal keepers and gorillas allow for this kind heart-health monitoring—and sharing this data with other conservation zoos can help monitor the health of the larger population.

The use of this technology has made it easier for staff to monitor and share data on the heart health of our gorillas, as recommended by the Great Ape Heart Project. It also allows our animal health team to recognize any changes taking place over time, potentially even before any problems or symptoms of heart disease develop. We have now added this kind of training—which the gorillas seem to enjoy—into the repertoire of all the gorillas, male and female, in both family groups. This is an essential element of maintaining good health and wellness for our gorillas—and it is all possible because of the strong bonds of trust that exist between the gorillas and gorilla keepers.

You can learn more about the Great Ape Heart Project here.