Hippopotamus (Hippopotamus amphibius) in the river Khwai, Okavango Delta, Botswana, Africa

hippopotamus hippopotamus amphibius river khwai okavango delta botswana africa hippopotamus hippo water river lake animal wildlife africa mammal submerged swimming resting large brown eyes closed day clear calm skin nature wild environment fauna savanna aquatic herbivore endangered species african wildlife zoology mammalogy wild animals conservation habitat ecosystem biodiversity natural world animal kingdom safari wildlife sanctuary