Sometimes fieldwork can be both mentally and physically exhausting, but for the most part, I am reminded just how lucky I am to find myself working in such a beautiful and isolated part of the world. I’m here in the deserts of Namibia, following waterways wet and dry to find and study the bats that depend upon them for survival.
From where my last post left off at the western end of the Hoanib River, I went along with Archie Gawusab, my local field assistant, north to Okongwe’s waterhole, seeing absolutely no one on the road, or rather 4×4 track, that day.
We netted at the artificial spring that evening. A herd of Hartmann’s mountain zebra joined us near the waterhole, but were too fearful to come and drink until after we wrapped up our fieldwork around 11pm that night.
After catching four bats earlier in the evening, Archie spotted a black rhino approaching the waterhole around 9:45pm. Like all rhinos I have seen in the field, this one was extremely cautious, but we went unnoticed downwind. Before it managed to reach the water, however, the zebra returned and chased off the rhino into the night.
The following day, we crossed the Hoanib again and went south into classic desert rhino habitat: dry, red, rocky, and quite barren. Several giraffe were at the Hunkab Spring when we arrived to investigate the site and many black-backed jackals were bouncing around.
We shivered in the ocean breeze that evening in our field clothes: the sandals, shorts, and jacket we use to wade through the water when retrieving bats from the net. We only caught one bat that evening—a Roberts’s flat-headed bat (Sauromys petrophilus). Several other individuals were flying around though and should show up on the bat detector.
Bat activity is usually related to temperatures, due in large part to a reduction in the activity levels of their insect prey on cold evenings. In the large river systems, temperatures are often buffered from cold extremes. The Hunkab Spring, however, lies outside of the shelter of a river’s canyon and the temperature dropped below 60°F by 10pm. This relatively cold temperature likely influences bat activity in the area, but the spring may be important for individuals traveling between the major rivers.
The next morning, a group of tourists informed us that they had just spooked off a black rhino from our netting site that night. I suppose we were off by a few hours this time to have the luck of another rhino encounter like the previous night.
Happy New Year
Yesterday evening (New Year’s Eve), we netted further south on our way back to the main gravel road. (As a quick reminder, I am writing this post on January 1, 2015, to be posted when I return from the field). It was another small natural spring where the Aub and Barab Rivers meet in the Palmwag Concession with plenty of fresh elephant tracks around. We caught a few vesper bats, increasing our species diversity count for this pilot season thus far to about 11 species over 10 nights.Extended, you can clearly make out the individual finger bones in the wing of a yellow-bellied house bat, Scotophilus dinganii. (Photo by Theresa Laverty)
I crawled into my tent at 11:59 PM and counted down to the New Year while listening to lions call in the distance and a hyena whooping nearby. This was my fourth time celebrating New Year’s Day in the field in Africa, but this year’s isolation made the night stand out among the rest. I cannot imagine a better way to celebrate the start of a new year.
Now, Archie and I are making our way south to the Huab River with hopes that the upcoming wet season does not interfere with our schedule.