Blue Wildebeest

Connochaetes taurinus

Blue Wildebeest Connochaetes taurinus grazing in a grassy field

Wildebeest are the “lawnmowers” of the Serengeti. They trim the grass and keep the savanna ecosystem healthy in some unexpected ways.

Range map of the blue wildebeest

Large herd of blue wildebeest gathering near a watering hole in the Serengeti grassland. Click for larger image.

Wildebeest live and migrate in vast herds on the Serengeti. Photo credit: iStock/Getty Images Plus

Wildebeest are herbivores from the Serengeti, a large ecosystem in Africa known for its diversity of animals. Blue wildebeest live in vast herds on the Serengeti grasslands.

Blue wildebeest (Connochaetes taurinus)

Every year, about 1.3 million wildebeest take part in one of the largest animal migrations on Earth. They follow the seasonal rains across the Serengeti, looking for green grass to eat. The wildebeest keep the grasses short and fertilize the ground with their waste as they go. But their influence extends beyond just keeping grasses healthy.

Small herd of blue wildebeest grazing in the Serengeti grassland. Click for larger image.

Large numbers of wildebeest reduce the frequency of forest fires, which allows trees to grow. Photo credit: iStock/Getty Images Plus

The huge population of wildebeest has the surprising effect of promoting tree cover. Before the 1960s, the Serengeti wildebeest population was kept relatively small by a disease. In later years, the disease disappeared, allowing the population to grow. By eating much of the grass, the rebounding wildebeest population reduced the frequency of fires (which need grass to burn and spread). Fewer fires led to more trees, which create healthy habitats for many animals ranging from herbivores to predators.

Aerial image of the Serengeti grassland in 1986 with low tree cover. Click for larger image.

Trees in the Serengeti in 1986

Aerial image of the Serengeti grassland in 1991 with moderate, recovering tree cover. Click for larger image.

Trees in the Serengeti in 1991

Aerial image of the Serengeti grassland in 2011 with dense, lush tree cover. Click for larger image.

Trees in the Serengeti in 2011