Zambia’s mass bat migration: top secret – but for how long?
Mark Carwardine | Issue 94 | 94 march 2008
I’m a bit embarrassed to admit what I’ve been doing this month. Most people will think I’m completely mad. I flew all the way to a remote corner of Zambia, in the rainy season, just to photograph a bat.
Actually, I went to photograph eight million straw-coloured fruit bats. For a few short weeks every year these endearing ‘flying foxes’ gather in a clump of trees in Kasanka National Park, close to the border with the Democratic Republic of Congo. I first heard about their record-breaking get-together a few months ago – it’s been one of the natural world’s best-kept secrets for years.
Tiny Kasanka is Zambia’s only privately managed park. About 520km north-east of Lusaka, it consists of 350 sq km of elevated plain covered in miombo woodland. It’s not the best safari destination in Africa, although it is one of the best places to see sitatunga (an elusive, semi-aquatic antelope), and its prolific birdlife is a draw for serious birdwatchers.
Raptors are everywhere – Wahlberg’s and crowned eagles, lizard buzzards and yellow-billed kites among them. And I saw a smattering of other wildlife, including a single herd of elephants, hippos, warthogs, side-striped jackals, baboons and umpteen pukus.
There were lots of creepy-crawlies, too – most of them in my thatch-roofed chalet at Wasa Camp in the heart of the park. Among my more spectacular visitors were a black-and-yellow-striped tiger snake, a couple of wonderfully hairy baboon spiders, a vivid-green praying mantis and a menagerie of moths, cockroaches, millipedes and ants.
Huge biting ants were everywhere. I didn’t do a scientific evaluation but there seemed to be a bigger biomass of them in Kasanka than anywhere else I’d been. Many of them set up base camp inside my trousers and my legs now look like a couple of spotty pubescent faces (albeit hairier).
But all that pales into insignificance in comparison with one of the greatest wildlife spectacles on earth. The twice-daily blizzard of bats with 80cm wingspans is more than ample compensation for a few nips
and bites.
I was up at 3.45am, and drove in the dark to the bat roost in a little swamp forest near the confluence of the Musola and Kasanka rivers. Then I waited.
The dark was lifting by 5am, and in the half-light I could see advance squadrons flying in to roost. By the time the sun was peeping over the horizon, the sky had filled with millions of noisily chattering bats returning from their night-time feast. They visit the park to feed on seasonal fruits and, between them, are reported to consume as much as 5,000 tonnes every night.
The show was over almost as quickly as it had begun and the bats settled in the trees. Hanging upside-down from every available branch and trunk, they filled the forest – bats, bats, bats everywhere.
They were restless, though, fidgeting and prattling and shuffling from one position to another. Occasionally one would squeeze out of the milling throng, clamber over all the other bats and hang from the lowest individual to get in position for a pee without drenching its bedfellows. Then it would shake itself dry and clamber back.
The night-time ritual was much the same. I’d wait on the edge of the forest as the sun set and, dead on 6.10pm, all eight million bats would rise from the trees and fly in bewildering numbers out into the gathering darkness. Several times I was standing directly underneath the swirling masses and was showered in sticky faeces, urine and vomit. What an honour.
I find it incredible that this extraordinary wildlife spectacle has been off the radar for so long. But it’s about to be filmed by the BBC, so it won’t be unknown for much longer. Whether it will survive (let alone benefit from) the inevitable onslaught of wildlife-watchers is another matter.
Mark Carwardine is an award-winning wildlife writer, broadcaster and photographer
Footnote