Silent Giants Are Dying Across Tanzania’s Plains, and Science Is Scrambling to Understand Why
By Adonis Byemelwa
On the ochre-dusted plains of Tarangire National Park, some of East Africa’s most iconic silhouettes are quietly vanishing. The African baobab, a tree that can live for over a thousand years, has long loomed over this landscape, its bulbous trunk towering over acacia scrub like a prehistoric monument. In recent years, however, researchers and park guides have started to see a disquieting trend: some of the oldest and largest baobabs are dying.
Baobabs do not tumble in a crashing thud that reverberates across the savanna, as hardwood trees do. Its wood is fibrous and water-logged; more sponge than timber. When they die, they typically crumple inward, gradually dissolving into a soft pulp that dries up and vanishes. In months, a tree that may have towered for centuries can be reduced to little more than a shallow depression in the ground.
Scientific interest in this phenomenon skyrocketed after a widely cited study in 2018, published in the journal Nature Plants. The study, led by researchers including Adrian Patrut, an expert in baobab trees from the Romania-based university Alexandru Ioan Cuza University in Iasi, focused on some of the oldest known baobabs throughout southern and eastern Africa.
It found that nine of the 13 oldest trees identified and some of the largest had died or experienced major structural collapse within a span of about a decade. Most of them were more than 1,000 years old; some were thought to be over 2,000.
The causes are not definitively established, and scientists have been careful not to extrapolate too much from them. The research itself did not pinpoint a specific pathogen or disease that caused the deaths.
Instead, researchers cited environmental stress from changing rainfall patterns and Temperature as factors likely contributing. Seasonal rains in parts of East Africa are more erratic now, characterised by lasting droughts and deluges that come on suddenly, only to vanish quickly. Such variability can put a strain on trees that rely on steady cycles of storing and using water.
Baobabs are specially prepared for dry climates. Such a large tree can accumulate tens of thousands of litres of water in its trunk and still put out leaves and fruit despite the harsh dry seasons. Though that system has limits. When dry spells last longer than average, or when rains fail in successive seasons, internal water stocks do not recharge completely. The tree can also have structural integrity injury over time.
In the Yaeda Valley (near Lake Eyasi), this change has ecological and cultural implications. The Hadzabe are one of the last remaining hunter-gatherer societies in East Africa, and have harvested baobabs both for food and shelter for centuries. The vitamin C-rich fruit is dried and ground to a powder that lasts for months. Hollow trunks can also be temporary shelter in or storage spaces for honey.
For members of the Hadzabe community, a big baobab lost is not merely a change in landscape. It can signify the loss of a familiar landmark and an invaluable resource. Researchers active in the region say such impacts are best described through local perspectives rather than blanket narratives about tradition. There is little data, except for glimpses of microclimatic leather in villages, but some communities describe fewer large fruiting trees in specific regions.
Wildlife is also affected. Baobabs are reportedly important for a variety of species. Elephants peel bark to get at moisture, particularly in dry seasons. Fruit bats feed on the pulp and disperse seeds, and insects and birds use crevices in older trees as nesting sites. When one big tree dies, the interactions change, placing concentrated pressure on the remaining individuals.
In Dar es Salaam, the country’s most populous city, baobabs confront a different set of pressures. Urban sprawl has pushed roads, housing developments and commercial projects into areas where old trees once thrived uninterrupted. A few famous baobabs have become local landmarks, sometimes attracting public scrutiny when their future is at risk due to construction. Conservationists say that while development is needed, the destruction of trees centuries old is an irretrievable loss.
At the same time, scientists have warned of regeneration. In some regions of Tanzania, there seems to be a gap between very old trees and younger ones. This “missing generation” has been observed in the field, although its causes remain under investigation. Potential reasons are grazing pressures on seedlings, alterations in fire regimes and changes in rainfall patterns that make it harder for young trees to establish.
Despite these challenges, baobabs are not all in decline. Many trees across East Africa are still healthy, and in some areas, populations seem stable. Scientists warn against recommending that the issue take shape as a simple narrative of collapse. Rather, they describe a more complicated system where certain age classes, especially the oldest individuals, may be more susceptible to environmental stress.
Tourism has been one way to support conservation efforts, although its role is not without debate. The lodges and safari operators in and around Tarangire National Park support community projects and conservation programs. Properties such as Tarangire Treetops by Elewana and ChemChem Lodge are linked to broader initiatives that support wildlife corridors, anti-poaching patrols and local employment.
These programs commonly involve monitoring large baobabs, conserving their habitats and providing assistance with community land management. In some cases, benefits from tourism are shared with neighbouring villages, making it economically advantageous to retain natural features like old trees. Nevertheless, experts say the effectiveness of such initiatives is all over the map and widely depends on governance, transparency and long-term commitment.
Other projects have more explicitly involved restoration and reforestation, sometimes combining baobabs with other native species. Since baobabs are slow-growing trees that can take decades to mature, these efforts are inherently long-term. In fact, it is often as important to protect young trees from grazing and fire as it is to plant new ones.
The changes are professional and personal for park guides in Tarangire. Many have laboured for years in the same patches of soil, even decades, growing familiar with particular trees. Some guides are able to name specific baobabs that were once regular stops for visitors but are not there anymore.
Even standing beneath an ancient baobab can be an astonishing experience. At times wider than a small building, the trunk carries scars from animals, weather and time. In places, carvings of past visitors are still faintly visible, although such practices are now discouraged. These trees link landscapes of today to a rich ecological past.
It is an open question whether recent trends represent a permanent change or a temporary state of affairs. What is certain is that baobabs, though tough, are not invulnerable to changes in their environment. Their longevity, which was once considered a guarantor of permanence, instead can make them sensitive barometers of slow-moving stress.
With the dry season well established over northern Tanzania, the remaining baobabs remain dotting the plains, their silhouettes still unchanged to a passing observer. However, close up, each of those trees has a different story to tell, a story of growth and survival or, in some cases, decline.
For scientists, conservationists and local communities alike, deciphering those stories has become an urgent job, one driven not just by the need to save a species but by the need to sustain landscapes and livelihoods that have relied on it.
