What do giant fruit bats have in common with Johnny Appleseed? Tonight’s episode of “One Strange Rock,” National Geographic Channel’s documentary series about the interconnectedness of Earth’s ecosystems, provides an answer that’ll awe the grossologist in your family.
During each rainy season, between October and December, up to 10 million of the bats — also known as flying foxes — converge on Zambia’s Kasanka National Park from all over Africa.
“It’s the largest mammal migration on Earth,” conservationist Frank Willems says in National Geographic’s video clip, available via GeekWire as an exclusive preview for tonight’s show. “They fly out in every direction, covering an area of 10,000 square miles.”
The bats gorge themselves on the waterberries, mangoes, musuku fruit and red milkwood berries hanging from the park’s trees, eating enough to equal half of their body weight each night.
As the bats fly back and forth, the fruit and the seeds pass through their digestive system — and yes, National Geographic shows that part of the process, using what appears to be an internal gut-cam. Then the seeds come out the other end and drop to the forest floor.
“The seeds might end up in a completely different place where a new tree can then grow,” Willems says. “We are looking at literally billions of seeds flying all over the continent.”