Gangly bodies splattered with yellows and browns, towered over our vehicle. I started counting each giraffe, growing increasingly frantic as more emerged from the nearby riverine forest. “29…30…31,” I exclaimed in awe. We watched the massive tower (the collective noun for a group of giraffes) for another fifteen minutes before finally finishing our observations. I sank back in my seat, determined not to let our research impede my appreciation of this event. I, like many others, have always held a special place in my heart for giraffes. If you had asked me twelve years ago if I would ever experience these animals in their natural habitat, I would have smiled and exclaimed “yes,” without a doubt. However, as time went on and my childhood optimism began to fade, this notion became more of a fantasy than a foreseeable future. But against all odds, here I was in the middle of the Masai Mara, surrounded by thirty-one giraffes. I couldn’t help but smile as I watched them, finally feeling like a ten-year-old again.
I had the opportunity to visit Masai Mara, Kenya, staying at the excellent Mara Trails camp, with twelve other Penn State students in January of 2023. The goal of this experience was to introduce students interested in ecology to the savannah through a research project of their choice and at the same time become immersed in photography. My group undertook an observational study on the vigilance behaviors of the Masai giraffe (Giraffa tippelskirchi). Through this study, I was able to gain a renewed appreciation for and interest in the complexities of the giraffe life cycle.
Social behaviour of giraffes
Despite being the tallest land animals in the world, a giraffe comes into this world with a high risk of death by predation. Mothers isolate themselves and their babies in an effort to protect them from this fate. Once strong enough, the mother will bring her baby to a tower, where the giraffe will continue to mature. Females tend to associate with females they are related to for most of their lives, staying in towers consisting of mainly females and subadult giraffes. Males join bachelor groups, only rejoining female-dominated towers when ready to mate.
Furthermore, giraffes form fission-fusion groups, meaning they consistently switch towers, perhaps learning more about the availability of food and predatory threats from the new group. The seemingly random switching between towers led researchers to believe that giraffes were incapable of significant social attachments and other behaviors for many years. Their social nature was only uncovered once researchers paid attention to subtle behaviors that often go unnoticed. These include giraffes observing each other for periods of time (and responding to the body language of this giraffe), grooming tower members, and mothers grieving the loss of their calves. Though it is still not fully understood how giraffes communicate and form bonds, these observations strongly suggest that they are creatures capable of strong social behaviors, similar to elephants or orcas.
I spent two weeks in the Mara, and dedicated most of this time to the Masai giraffe. We chased them across the savannah, and observed them in a variety of habitats throughout the day. Each moment spent with them was a wonderful opportunity to unearth even more of their subtle complexities. I learned that young males dedicate much of their time to “play fighting,” in preparation for the brutal battles adults undertake for mating and territorial rights (which can result in severe injury or even death).
In addition, I learned that giraffes have excellent eyesight, and take turns scanning the surrounding savannah for threats, while other members of the tower eat or ruminate. Even giraffe rumination was endlessly interesting, as they appear to be capable of rumination during a non-REM sleep state. These ruminating giraffes were essentially zombies, dead to the world yet still functioning as if they were aware. Though all of these behaviors and characteristics were undeniably fascinating, I was most enamored by the symbiosis between giraffes and the oxpecker bird.
Oxpeckers- friends or parasites?
Upon completion of this once in a lifetime trip, I had a moment to look through the photos I had taken, and noticed something odd. Virtually every photo I had of the giraffes featured an Oxpecker, typically perched on the back of one or two of the animals. I looked into the strange phenomena, and uncovered an interesting story. The yellow-billed Oxpecker (Buphagus africanus) –the most common Oxpecker I saw, although red-billed Oxpeckers were also common – has a mutualistic relationship with a variety of ungulates, including giraffes, gazelles, zebras, water buffalo, and many others. It eats ticks and a variety of other arthropods from the coat of the animals. From this, the Oxpecker receives a meal while the ungulate is protected from the diseases these arthropods could inflict. I found this mutualistic relationship fascinating, as I had never seen (or even heard) of such a successful mutualism between two large vertebrates.
Furthering my research into this topic initially left me with more questions than answers. The Oxpecker-giraffe mutualism is undeniably successful. However, it is a very imperfect mutualism. Some experts have even considered calling the symbiosis a parasitic relationship due to these imperfections. The confusion in classification stems from the Oxpecker’s tendency to keep wounds open and then to feed on blood. This has led experts to suppose that the ticks and arthropods they ingest are just simpler methods for obtaining blood from the animal, and that if exposed tissue was made more accessible, the Oxpeckers would directly consume this instead.
Studies have revealed that Oxpeckers prefer ungulates with more ticks as well as a larger surface area. This suggests that the relationship is primarily mutualistic, although the definition is still close to that of being parasitic. I would therefore not be surprised if it was reclassified once again in the future. The complexities of a symbiotic relationship that was so prominent, and easily observable, surprised me. How can we know so little? This question inspired me to reconsider my experience with the giraffes. Here I was, staring at 31 of the tallest land animals in the world. They were so close that I could watch every blink, muscle twitch, and head bob. I observed them, virtually for 2 weeks straight, and was left essentially clueless. I am not alone in this frustrating experience. Scientists have been studying these animals for years, and still claim they have only scratched the tip of the iceberg in terms of fully understanding these captivating organisms.
My experience in the Mara not only changed how I view giraffes, but changed my entire view of ecology. I realized that signals imperceivable to humans (such as giraffe communication) are being sent at all times in the natural world, and that important relationships (such as the giraffe-oxpecker mutualism) are silently at the forefront of the mechanisms that allow these ecosystems to run. Invisible systems surround us, and ecology is the key to uncovering them. Thanks to the silent relationships of the giraffes, I now feel the resurgence of my child-like wonder everytime I delve into my studies of ecology. As ecologists, we are the first explorers of the unseen worlds that control the environments we love. Can you imagine a better adventure than that?
