Gorilla wounds common as males grow into silverbacks

Gorillas Zola (left) and B’wenzi (right) interact in their habitat. Photo courtesy of Tom Harlan

Humans are squishy. It’s been a long time since our ancestors shared any of the strong, physical traits of the other great apes. And while those primates evolved to be big and tough, we did not.

As our brains began to develop instead, we became adept at using tools and learned to control fire, build shelters, and grow our own food. These advancements set us on a course to be very smart – and very squishy. We no longer needed to be big and tough, so those traits began to go away as we became more technologically advanced.

The other great apes continued down their own paths, which still require them to be strong, powerful animals. In their environments, being tough is the key to survival. It’s no surprise that a 450-pound gorilla with canine teeth 2-3 inches long can leave a nasty wound on another gorilla, and from time to time we see that here at the Zoo.

When cuts and scrapes occur in our gorillas, we’re always ready to treat and monitor them until every last scratch has healed.

So why do these herbivorous animals have such big teeth to begin with? Well, those teeth are for protection. Gorillas don’t have any true natural predators, although some research suggests the possibility of rare conflicts with leopards (definitely a good time for big teeth).

The most common threat to a silverback gorilla is generally another silverback. A male may try to challenge another to usurp his throne or steal females to build a troop of his own. Male gorillas have much larger canines than females, and they use those teeth to protect the females and youngsters in their troop.

If challenged, gorillas go through a long list of behaviors, trying to avoid a physical conflict. If you think about it, fighting someone means you’re just as likely to get hurt as they are, so why risk it? Gorillas are peaceful, laid-back animals that generally keep to themselves. In the wild, keeping a 400-pound frame of muscle while sometimes eating only the caloric equivalent of wild celery means there aren’t many good reasons to waste energy. However, when threatened, a male gorilla will not hesitate to defend his troop.

Fighting isn’t just a human trait, it’s part of life for much of the animal kingdom. Being that we’re so delicate, we’re used to even small wounds requiring attention, so our own experiences create a predisposition to react to wounds a certain way. Cutting your finger on a broken glass could require stitches, but in the middle of the jungle you don’t have the luxury of hopping in the car and heading to the hospital.

As bad as an open laceration may appear, it may not be that big of a deal for the gorilla. At the Dallas Zoo, we have an exceptional veterinary staff that can treat just about anything, and we don’t hesitate to call upon them when needed. Keeping that in mind, most animals are experts at taking care of their own wounds, and gorillas are no exception.

If you see a gorilla with an open wound, you may notice them grooming it with their fingers and utilizing nature’s ultimate antiseptic, spit, to keep it clean. As zookeepers, we keep a close eye on injuries to make sure things are healing appropriately, but when we can, we try to let the gorillas handle the job. The decision to anesthetize a gorilla to suture a wound is a carefully calculated risk/reward scenario, especially considering that more often than not that gorilla is going to hand you back those sutures within a few hours of waking up.

We train with the gorillas daily to make sure we can see every part of their body. We also desensitize them to being sprayed with antiseptic sprays, and we work on more complicated behaviors, like hand injections. If a gorilla were to need an injectable medication, which is rare, we want to get it to them in the least stressful way.

We also record even the smallest injuries. We use a very detailed system to document every injury and the details of the situation in which it occurred. Photographs are especially helpful, as they can be used as objective data to monitor the healing process. This information is not only important for individual injuries, but for enhancing our ability to treat future injuries.

In recent months, we have seen a few different wounds to gorillas in our bachelor troop. This troop consists of four 14- to 15-year-old males. Sometimes we see genuine social issues develop, while other times play just gets a little too rough.

Bachelor troops are a relatively new concept in zoos, so constant, adaptive management is the key to peace within the troop. Between the keeper staff and our volunteers in the Gorilla Research Station, we’re able to keep a close eye on all eight of our gorillas. This has been very important as we move into a new phase of troop management with the four bachelors.

This troop has been together since 2013, when Shana and Zola came to Dallas from the Calgary Zoo to join Juba and B’wenzi. When the boys were 10-11 years old, they started forming social relationships, which comes in handy as they get older. With the information we have as other institutions manage similar troops, we know that management of bachelors is most difficult between ages 14-20. Having similar life expectancies and developmental stages to humans, we understand why these years are the most difficult (right, parents?).

Bachelor troops exist both in human care and the wild, and they serve a number of purposes. As young males begin to grow, the silverback generally will force them out of the troop, avoiding a threat to his position. Sometimes those exiled males will band together and form bachelor troops. These groups are generally transitory, but allow for development of social behaviors and provide some degree of protection from outside threats.

In zoos, bachelor troops are used to manage unattached males. Gorillas have a 50:50 birth ratio, just like humans, meaning that having single-male/multi-female troops isn’t possible for everyone. Bachelor troops can provide healthy social environments for growing male gorillas, which are often more closely bonded than they would be with female gorillas.

With all of our social apes, we also see an increase in aggression during introductions and reintroductions, which is another reason we avoid more invasive and intrusive courses of treatment. When possible, we try to avoid separating the gorillas for long periods to make sure we keep aggression to a minimum when they get back together.

When animals are injured in the zoo setting, it’s important to know the team behind the scenes is on the job at all times. If an animal needs to be watched 24 hours a day, we’ll be here with them. If they need to receive medication at a certain time, someone will be there. Between the keeper staff and the vet staff, we do all we can for preventive and reactive care of our animals, and not a scratch goes unnoticed under the watchful eye of the animal staff here at Dallas Zoo.