HerdTracker, a free web-app which details the Great Wildebeest Migration, has shared images of what is believed to be one of the largest Mara River crossings in 25 years.

The video shows thousands of wildebeest charging across the Mara River from regular contributor Ranger Safaris Tanzania.

“This was one of the largest crossings I have seen in over 20 years,” says Emmanuel Mkenda, the Ranger Safaris’ guides who shot the footage, and who has been working in the area for 25 years.

Captured mid-September in the Kogatende area of Serengeti National Park in Tanzania, this was the largest Great Migration crossing captured on video in recent years. While wildebeest herds are usually scattered, a megaherd like this, estimated at between 80 000 and 100 000 animals, is extremely rare to see.

Each year, more than 1,5-million wildebeest migrate in a gigantic clockwise loop across Tanzania and Kenya. After calving in the southern part of Tanzania’s Serengeti, the animals journey north into the Masai Mara, before returning once again near the end of the year.

These massive herds follow the seasonal rains across the African savanna in search of lush grazing lands, often pursued by predators such as hyenas, lions, cheetah, leopards and, at the many river crossings, gigantic Nile crocodiles. Dramatic scenes unfold daily as thousands of wildebeest are born and killed while the circle of life revolves non-stop.

Recognised as one of the seven wonders of the natural world, this incredible phenomenon also includes hundreds of thousands of other grazing animals like zebra and gazelle.

HerdTracker was launched in 2014, plotting the location of the Great Wildebeest Migration in realtime to a Google map and in a Twitter-style timeline.

It delivers crowd-sourced updates – more than 1 500 since inception – provided by pilots, safari guides, rangers, lodges and even safari-goers from hot air balloons.

“Capturing and sharing these spectacular safari moments is exactly why we developed HerdTracker,” says Andre Van Kets, CEO of Discover Africa Safaris.

a group of wildebeest crossing the Mara river in northern Tanzania, Africa