A serval is seen on the grassland at Maasai Mara National Reserve in Kenya, June 17, 2019. (Xinhua/Li Yan)

A lion rests on a tree at Maasai Mara National Reserve in Kenya, June 17, 2019. (Xinhua/Li Yan)

A crocodile rests on the water side at Maasai Mara National Reserve in Kenya, June 17, 2019. (Xinhua/Li Yan)

A lion rests in the grass at Maasai Mara National Reserve in Kenya, June 17, 2019. (Xinhua/Li Yan)

A lion shakes its head to drive away flies in the grass at Maasai Mara National Reserve in Kenya, June 17, 2019. (Xinhua/Li Yan)

Two buffalos fight against each other at Maasai Mara National Reserve in Kenya, June 17, 2019. (Xinhua/Li Yan)

Balearica regulorums forage on the grassland at Maasai Mara National Reserve in Kenya, June 17, 2019. (Xinhua/Li Yan)

A giraffe is seen at Maasai Mara National Reserve in Kenya, June 17, 2019. (Xinhua/Li Yan)

A fox is seen at Maasai Mara National Reserve in Kenya, June 18, 2019. (Xinhua/Li Yan)

An ostrich forages on the grassland at Maasai Mara National Reserve in Kenya, June 18, 2019. (Xinhua/Li Yan)