Bat Field Weekend to Thabaphswa – 20-22 October 2006

By Julio Balona

 

On a hot October night in the rocky rrrugggged mountains of Thabaphaswa [1] (about fourteen kilometres outside Mokopane) and under the supervision of the naboom trees we erect:

1 x Harp trap

3 x Mist nets

1 x Lava lamp (sorry that’s a different trip I’m thinking of…) 

We braai, converse and make regular patrols of the nets and trap, hoping to find a captured bat to start the evening off. There are Red Toads all over the place revealing their presence by disturbing the dead leaves every time they hop about in the dark. In the pond near the campsite, frogs are calling loudly and I’m thinking this has got to be cobra country with so much food flaunting itself everywhere. On one of the many patrols, I see a Cape wolf snake slither into the leaf litter. This snake is a skink specialist hence the sharp wolf like teeth. Seems the frogs know something I don’t. 

It’s entertaining when Erna and I realise that the LEDs in our headlamps reflect off the eyes of numerous small spiders wandering about all over the place. Later, Dawn spends some time peering down a small hole, trying seriously to photograph a crab spider which is a kind of wolf spider (really, that’s what she said). Thabaphaswa is literally crawling with interesting creatures. 

Oh yes, I forget we’re here for bats! 

At about 20h00, we caught this guy in one of the nets: 

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Photo: Julio Balona 

Although he looks like he may be a member of the genera Hobbit (careful inspection reveals rather quaint hairy feet), we decide he’s an Egyptian free-tail bat, which some are tempted to call Yoda: 

Although he is not an uncommon bat species, we are happy to get a close up look as we don’t often catch free-tails due to their inconvenient preference for flying higher than our nets. Unfortunately he solely represented our tally for the evening. We take down the nets but leave the harp trap up. We are surprised at how few bats we’ve caught and I’m tired but I’ve got a good buzz going because I’m surrounded by interesting life and comforting dark mountain silhouettes.

The next morning, a manically bright and cheerful sun conspires with a snoring partner so that sleeping late is not permissible. Happily we find that a bat has been caught in the harp trap some time during the night. It looks like a Cape Serotine but seems smaller. We measure it, examine it, take a biopsy and then leave it in a quiet and cool place. Later in the evening we release it in the flight tunnel and record its call. When I analyzed the call a few days later its peak frequency was at about 50 kHz and that tells me it may have been a Rusty pipistrelle. I await the results of the biopsy DNA analysis to confirm this identification.  

In the meantime, I hope he is cheerfully flying about and the “aliens” that abducted him, held him captive and removed a very small piece of his flesh have been forgotten. 

It gets rather hot, rather quickly and plans for hiking are deemed absurd. Despite the heat, there is a pale Foam Nest Frog sitting passively and dare I say it, tanning on top of a tree? I’m tempted to coax it down and give it a stern lecture on the danger of skin cancer; smearing it with SPF 40 sun block also crosses my mind! But, it seems content incubating an ancient wisdom about what amphibians can or cannot do, so I leave it alone. 

We make our way to “our oasis”, the farm reservoir, about 2Kms away. The quenching water is deep and cool and we decide that this is where we will set up our bat capturing devices tonight. Turns out, the bats think the reservoir is deeply cool too; that night, our mist net, that we have erected over the reservoir, catches four different species: 

Egyptian free-tailed bat?
Long-tailed serotine bat?
Yellow house bat?
Schriebers’s long-fingered bat?

I write Egyptian free-tailed bat with a question mark because weeks later when I looked at its measurements and the call that was recorded, it appeared to me that if it was an Egyptian, it was smaller than normal and had a higher pitch voice (you know, like a dainty falsetto bat or something). Which is feasible but I have started wondering if it was instead the scarcer Flat-headed free-tailed bat. It’s not that unlikely; the Flat-headed version likes crevices and exfoliating rock layers of which there is no shortage at Thabaphaswa. But as Zuma probably said to Shaik:  ‘No one will ever know’.  And now we have an excuse to return to Thabaphaswa. 

The Long-tailed serotine is quite a dish. Please peruse its pelage [2] which is truly golden: 

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Photo: Julio balona

The Yellow house bat is released immediately because it was a female and seemed to be pregnant. 

The Schreibers’s long-fingered bat seems the least impressed with being kidnapped and makes indignant ‘kreek, kreek’ protestations. 

Later in the evening Nigel, with a few backup batters, drives a short distance away to the homestead where Egyptian slit-faced bats are known to have a night roost. We managed to catch one with a handnet and bought it back to the camp so that the rest of bat fiends can have a look. After the measurements were taken and murmurs of admiration of its large ears lulled, she is released. 

The next day before we leave, Dawn shows me a solifugid (‘Red Roman spider’) and a pair of stalk-eyed flies that she has found.  

Heck I would have come to Thabaphaswa even if there were no bats.

[1.] Mokopane = Potgietersrus for those of you who have had trouble keeping up with all of the name changes
[2.] What mammalogists call fur