A keystone species is one that has a disproportionately large impact on its ecosystem, influencing biodiversity, landscape structure, and resource availability. Few animals fit this definition as perfectly as elephants. At Tsavo Trust, our core mission is to protect and monitor the great African elephants of the Tsavo Conservation Area, and in doing so, we see firsthand how elephants shape their environment, benefiting a vast array of wildlife. From creating waterholes to dispersing seeds and managing grasslands, elephants play a fundamental role in maintaining the balance of Africa’s ecosystems.
In this article, we explore the many ways elephants act as keystone species and why protecting them is crucial for the health of our natural world.
Elephants as waterhole creators
In dry landscapes like Tsavo, water is one of the most critical resources for wildlife survival. Elephants are essential in ensuring that water remains available, particularly during droughts.
Digging for Water: Elephants use their trunks and tusks to dig into dry riverbeds, accessing underground water. These holes create vital drinking spots for other animals, including antelope, zebras, and predators like lions.
Termite Mounds and Waterholes: Elephants also dig into abandoned termite mounds in search of mineral-rich soil to supplement their diet. Over time, these excavations form depressions that collect rainwater, eventually becoming long-lasting waterholes.
Expanding Water Sources: Once a waterhole forms, elephants continue to use it for bathing and wallowing. As they churn up the mud, the hole deepens and expands, ensuring it holds water for longer periods.
These waterholes become essential oases, supporting countless species and helping entire ecosystems survive through harsh conditions.
Elephants as grassland managers
Elephants are vital in preventing savanna ecosystems from becoming overgrown woodlands. Their feeding habits help maintain the balance between grasslands and forests.
Controlling tree growth: Elephants feed on young acacia trees, stopping them from taking over open grasslands. This ensures that grazers like wildebeest and zebra have access to the grasses they depend on.
Maintaining habitat diversity: By keeping tree growth in check, elephants create a mosaic of habitats—open grasslands, shrubland, and woodlands—each supporting different species.
Preventing bush encroachment: Without elephants, acacia trees could dominate, reducing the open spaces needed for many herbivores and, in turn, the predators that rely on them.
Through their constant movement and foraging, elephants shape the landscape, maintaining the delicate balance of the savanna ecosystem.
Elephants and climate change resilience
As the climate changes, ecosystems must adapt. Elephants play a crucial role in helping plant species shift to new areas where conditions are more suitable.
Seed dispersal: Elephants consume large quantities of fruit and vegetation, often swallowing seeds whole. These seeds pass through their digestive system and are deposited in dung, sometimes over 60 km from the parent tree.
Facilitating migration of plants: As temperatures rise, some tree species will need to colonise new areas. Elephants act as natural transporters, ensuring seeds reach places where they can thrive under changing climatic conditions.
Creating future forests: Some tree species, like Balanites wilsoniana, rely almost entirely on elephants for seed dispersal. Without elephants, these trees would struggle to regenerate.
Elephants don’t just shape the present landscape—they also help forests and savannas adapt to the future.
Dung-driven biodiversity
Elephants’ inefficient digestive system means that much of what they eat remains undigested, making their dung rich in nutrients and seeds. This plays a crucial role in supporting biodiversity.
Seed germination: The nutrients in elephant dung help seeds sprout, increasing plant diversity.
Food for insects and birds: Dung attracts dung beetles, which lay their eggs inside, creating a food source for their larvae. Birds like spurfowl and even baboons rummage through elephant dung for undigested seeds and insects.
Nutrient cycling: By breaking down plant material and redistributing nutrients across the landscape, elephants enhance soil fertility, benefiting plant growth and the wider ecosystem.
Even after it leaves an elephant’s body, dung continues to support life in remarkable ways.
Even in death, elephants shape the ecosystem
An elephant’s impact on the environment continues long after its death. When an elephant dies, its carcass supports an entire network of scavengers and decomposers.
A feast for scavengers: Vultures are the first to arrive, feeding on softer tissues while waiting for larger predators. Hyenas follow, using their immense jaw strength to break through the tough hide.
Supporting biodiversity: Over time, lions, marabou storks, and insects such as maggots join in, ensuring that every part of the elephant is consumed.
Enriching the land: Blood and fluids from the carcass seep into the soil, creating a nutrient-rich patch that supports new plant growth. Even the bones are eventually broken down by hyenas or left to fertilise the earth.
Through this process, an elephant’s presence continues to shape the landscape, reinforcing its role as a keystone species even in death.
Balancing the impact of elephants on ecosystems
Overgrazing during droughts: When food is scarce, elephants strip bark from trees to access nutrients, often killing the tree in the process.
Tree-felling behaviour: Large bulls may push over trees to access foliage, altering the landscape and affecting species like giraffes that depend on tall trees.
Human-wildlife conflict: In areas where migration routes are blocked, elephants may overuse limited resources, leading to conflict with local communities.
Conservation strategies must focus on balancing elephant populations with habitat protection to ensure sustainable coexistence, one strategy for this is making sure there are enough wildlife corridors to allow elephants to move from one place to another.
Elephants are true keystone species
Elephants are true keystone species, shaping landscapes, maintaining biodiversity, and ensuring ecosystem resilience. Without them, Africa’s ecosystems would look dramatically different—water sources would be scarcer, grasslands would shrink, and forests would lose key tree species.
At Tsavo Trust, we are dedicated to protecting elephants and the landscapes they sustain. By conserving elephants, we are not just saving one species—we are preserving the intricate web of life that depends on them.
Join us in our mission to protect Tsavo’s wildlife. Support conservation efforts today and help safeguard the future of Africa’s ecosystems.