Hello everyone,
Sorry it’s been so long. Last I wrote I was still learning to drive the car. After all this time you must have thought I’d driven it into an elephant or some such. Well, it’s been nothing quite so catastrophic, I’ve simply been working day in, day out every day of the week it seems. Between work and sleep I haven’t really allotted any time for communication with the outside world (sorry!) but now my guilt compels me to tell you at least a little bit of what I’m doing out here and what I’ve been up to out in the savanna.
My research question deals with the effects of anthropogenic nutrient loading on primary, secondary and tertiary productivity in the savanna. Historically, herders in this region of Kenya (and actually much of East Africa) used to pen their cattle in great big corrals called “bomas” overnight to protect them from predators. With such a high concentration of cattle spending the day grazing elsewhere and the night defecating all in one place, these bomas end up with tons of nutrients – instant fertilizer. When eventually the cattle move on to a new boma they leave a small, treeless area, rich with nutrients that soon blossoms with grasses becoming a “glade.” These glades persist for decades, perhaps even as much as a century creating really interesting patterns across the landscape.
So we already know that this increased abundance of nutrients results in higher levels of primary productivity (plant growth), but my research is investigating whether that increase then cascades to higher trophic levels. Remember the trophic pyramid with plants on the bottom, herbivores above (eating) them and carnivores above that? This is the gist of my research – to what extent are humans, through this livestock practice, changing those interactions?
To do this I’ve constructed 20 transects, each about 100 m long radiating away from many glades around Mpala. I’ve been walking these transects, tagging each of the trees, recording height and distance data for days. I’ve now tagged some 1030 trees and I’m ready for the next stage.
This week, I’m revisiting all of these trees in search of my lizard species. I’ve got a picture of them above. So far so good but it’s been a lot of work! I’ll update you with some more stories in the field soon (I promise!).
Colin Donihue 