The iconic image of vast herds of wildebeest thundering across the African savanna has captivated audiences around the world. However, new research shows that these epic migrations are becoming increasingly rare due to human activities such as roads, fences, farms, and urban sprawl that have disrupted their historic migratory routes. A study conducted by researchers from the University of Copenhagen has found that non-migratory wildebeest populations are genetically less healthy compared to those that continue to migrate. This genetic decline could have long-term consequences for wildebeest herds, especially in the face of climate change.
The genetic health of wildebeest populations is reflected in various parameters such as lower genetic diversity, increased genetic isolation, and inbreeding. This could lead to lower survival rates, reduced fertility, and other negative effects on the overall fitness of these animals. Researchers analyzed the whole genomes of 121 wildebeest from their entire range, spanning from South Africa to Kenya, making it the first study to investigate the genetic effects of migration in wildebeest. The results showed a clear difference in genetic health between migratory and non-migratory populations across multiple locations.
While the wildebeest population as a whole is not currently threatened, the long-term consequences of disrupted migrations could make them more vulnerable, particularly in the face of climate change. The ability of wildebeest herds to adapt to environmental changes is reduced in populations with low genetic diversity, posing a threat to their survival. The researchers hope that these findings will prompt further investigations into the genetic effects of reduced migration on other species and encourage decision-makers to prioritize the preservation of natural migratory routes.
The only remaining major wildebeest migration is the “Great Migration” in the Serengeti-Mara, where approximately 1.3 million wildebeest, along with zebras and gazelles, cover up to 3,000 kilometers annually following seasonal rainfall patterns. Historically, there have been several wildebeest migrations comparable to the Serengeti-Mara population, but many of these migrations have been lost due to human activities. For example, the Eastern white-bearded wildebeest subspecies, known for its historic migration centered around Kenya’s Kajiado County, has declined to only 6,000-8,000 individuals due to increased human presence and activities.
As a keystone species in ecosystems, wildebeest play a crucial role in maintaining healthy vegetation, distributing nutrients, and supporting predators and scavengers. The disruption of their migrations not only threatens the survival of wildebeest but also impacts the entire ecosystem. The researchers emphasize the importance of preserving natural migratory routes for wildebeest and other migratory species in Africa and beyond to ensure their long-term survival and genetic health. By raising awareness of the genetic consequences of disrupting migration patterns, the hope is that decision-makers will take action to protect these iconic species.
