World's biggest bat colony gathers in Zambia every year. Researchers used artificial intelligence to count them

Everybody who visits Kasanka National Park in Zambia during "bat season" agrees that the evening emergence of African straw-colored fruit bats from their roost site is one of the wildlife wonders of the world. The bats (Eidolon helvum) arrive at Kasanka every year around October. The numbers swell rapidly until they peak in November. By January they are gone again.