Baobab trees, long considered symbols of resilience across Africa and beyond, are now facing a potential new threat from a destructive beetle species known for damaging fruit trees. Researchers have discovered that the mango stem borer is attacking and killing baobab trees in Oman, sparking concern among scientists about the possibility of wider impacts on these iconic trees.
The warning comes from a recent study examining a small population of baobabs in Wadi Hinna, a semi-arid valley in Oman. Scientists found that six trees had already died, while at least twelve others were severely infested by the larvae of the mango stem borer, a beetle species known scientifically as Batocera rufomaculata.
Researchers discover unexpected pest attack on baobabs
The research was led by Sarah Venter, who investigated the health of around 100 baobab trees in the valley at the invitation of Oman’s environmental authorities. After examining the damaged tissue of 90 trees, the researchers discovered that larvae of the mango stem borer were burrowing deep inside the trunks.
Female beetles cut small openings in the bark to lay their eggs. When the larvae hatch, they tunnel through the fibrous wood of the tree for months, creating zigzag feeding channels that gradually weaken the trunk. Over time, the structural damage becomes so severe that the tree can collapse under its own weight.
Baobabs belong to the genus Adansonia and are among the most distinctive trees in the world, known for their massive trunks and extraordinary lifespans that can exceed 1,000 years. The most widespread species, Adansonia digitata, grows across large parts of Africa.
Authorities move quickly to protect remaining trees
Following the discovery, government agencies in Oman launched a control program to prevent the infestation from spreading. Officials are applying pesticides to affected trees, installing light traps to attract adult beetles at night, and manually removing larvae from tree trunks using wire hooks.
Researchers say these measures appear to be helping protect the small and isolated population in Wadi Hinna. However, they warn that such intensive efforts would be far more difficult to implement in regions where thousands of baobab trees grow across large landscapes.
Scientists warn of potential biosecurity risks
Although the mango stem borer is widely known to damage mango and fig trees across Asia, the infestation of baobabs appears to be rare. Scientists say it remains unclear why the pest is severely affecting baobabs in Oman but has not yet caused similar damage in regions such as Madagascar, Mauritius, or Réunion, where both the insect and baobab species exist.
Researchers suggest that environmental stress or limited food sources in Oman could be making the trees more vulnerable to the beetle.
The findings, published in the journal Global Ecology and Conservation, also highlight the importance of stronger plant biosecurity measures. Scientists warn that transporting live plants, cuttings, or fruits between regions could unintentionally spread harmful pests to new environments.
Experts say preventing the introduction of invasive species will be essential to protecting baobabs, which are not only ecological landmarks but also culturally significant trees across many parts of Africa.