In my first post I described the experiment I’m starting in Gorongosa. I want to know if there are fewer or smaller pans (small seasonal ponds), or pans with different animals living in them when there are fewer elephants, buffalo, warthogs, and other mammals digging around in the mud. This is relevant because large mammals declined in Gorongosa during the civil war, but are now recovering. How do changes in mammal populations affect the park’s aquatic habitats and species?
Photo: A male bluefin notobranch killifish; these are popular aquarium fish, but native to seasonal pans in Mozambique and South Africa.
In the first three weeks I’ve picked the pans I’ll study, and today I started capturing animals in the pans. It was a biodiversity bonanza. In just the third net scoop I made today, I caught my prized target: a bluefin notobranch killifish, Nothobranchius rachovii. I’d been reading about the fish since November! The fish has one of the shortest adult life spans of any vertebrate—just a few months—during which time it lays eggs in pan soil. The eggs require a few months dried out, and so the fish only live in seasonal waterbodies like Gorongosa’s pans. Bluefin notobranchs are popular aquarium fish, too; not hard to see why, given their bright colors.
Photo: A male brooding water bug Diplonychus sp. carrying eggs.
The fun didn’t end after I found the fish. Later I caught a few large waterscorpions (Laccotrephes sp.), about four inches from head to tail. These guys are harmless to humans, but voracious tadpole predators! A final neat find, was a male brooding water bug (Diplonychus sp.). These guys carry their eggs around after the female “glues” them to his back! Way cool.
Photo: Harmless to humans, this water scorpion is about 4 inches long and unrelated to true scorpions.
As if the day weren’t exciting enough, on the way back to camp and our proto-lab, we ran into a large herd of elephants crossing the road just a few hundred meters north of Chitengo! Seven elephants crossed the road, with more waiting behind. Once our guard, Batista, gave the go ahead we pushed through, back home.
Photo: Park guard Batista and my field assistant Flavio with our field gear beside one of Gorongosa’s pans.
I’ve had a load of help from a few university students finishing their studies in Chimoio, especially m field assistant, Flavio. Today he told me, “Josh, to miss a day in science is to miss a year.” I don’t know if that’s always true, but today it sure was. Come on out to Gorongosa and have the best days of your year!
By Joshua Daskin
PhD Student, Department of Ecology and Evolutionary Biology