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WonderNatural migration fact

Every year more than a million wildebeest, joined by hundreds of thousands of zebras and gazelles, walk a great loop through Tanzania's Serengeti and Kenya's Maasai Mara, following the rains to fresh grass.

Great wildebeest migration

MigrationClimateNatureBiologyScience

The story behind the card

The herds have no fixed route; their path shifts each year with the rain. Early in the year hundreds of thousands of calves are born within a few weeks in the southern Serengeti. As the plains dry out the herds move north and west, reach Kenya's Mara in the middle of the year and return south when the short rains begin. The most dangerous moment is crossing the Mara River. A 2017 study found that on average about 6,250 wildebeest drown there each year, and their carcasses, some 1,100 tonnes, feed fish, crocodiles and vultures and fertilise the river for years. Grazing herds also keep the grasslands healthy.

Türkçe oku
Her yıl bir milyonu aşkın gnu, yüz binlerce zebra ve ceylanla birlikte Tanzanya'daki Serengeti ile Kenya'daki Masai Mara arasında büyük bir daire çizer; yağmurların yeşerttiği taze otların peşinden gider.

Sürülerin sabit bir rotası yoktur; izledikleri yol her yıl yağmura göre değişir. Yılın başında Serengeti'nin güneyinde birkaç hafta içinde yüz binlerce yavru doğar. Ovalar kurudukça sürüler kuzeye ve batıya ilerler, yaz ortasında Kenya'daki Mara'ya varır, kısa yağmurlar başlayınca da güneye döner. Yolculuğun en tehlikeli anı Mara Nehri'nin geçişidir. 2017'de yayımlanan bir araştırmaya göre burada her yıl ortalama 6.250 gnu boğuluyor. Toplam 1.100 tonu bulan leşler balıkları, timsahları ve akbabaları besliyor, nehri yıllarca gübreliyor. Otlayan sürüler de otlakların sağlıklı kalmasını sağlıyor.

Sources and further reading

Background reading: Serengeti National Park
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