Yet another comparison of Houston to Tanzania–in Houston, it’s hardly a surprise to see a few dozen pieces of litter within eyeshot. Even in the bayous, which we are so proud of, it’s not unusual to see more trash (and even furniture) floating on the surface than water. In Tanzania, however, it is a jarring sight when a plastic bag blows across an otherwise seemingly untouched savanna. On the surface, this is unsurprising, even logical.
However, this “seemingly untouched” landscape is inhabited and shaped by humans–the Maasai people, who have lived in the area for over 150 years. The Maasai are pastoralists, leading herds of cows, goats, sheep, and donkeys across northern Tanzania and southern Kenya through and beyond the Serengeti ecosystem. The charismatic images of Serengeti scenes are not only taken on Maasai land, but also enabled by the lifestyle of the Maasai. Their pastoralism and temporary residences called “boma,” play a large role in nutrient cycling through nearby ecosystems and creating the landscapes that we see, rotating through grazers to close crop the grass and reduce the occurrence of fires.
TLDR: The landscape of the Serengeti ecosystem has been and is shaped by the Maasai.
This morning, we set off to a seasonal watering hole half an hour from our camp at Olduvai to perform a series of transects to quantify the population density of animals in the area by, well, surveying their poop. On our drive out through picturesque savannah, there were only small traces of human settlements: an empty water bottle here, a plastic bag there. When we arrived at the site, however, the dried up watering hole was unmistakably shaped by the Masaai who had lived there until recently. The abandoned boma was marked by shrubs cut down and arranged to create distinct areas for livestock and human inhabitants. Other than this, and a stray shirt snagged on an acacia tree, upon first glance the area seemed relatively untouched.
This perception changed almost immediately when we began our poop transects. For those of you who are unfamiliar with the transect and quadrat method, we set up several transects, or walking paths, of a set length, upon which we lay down a quadrat (essentially a PVC rectangle with predefined dimensions) at set intervals. We planned a survey including parallel transects beginning the same distance from the edge of the dry watering hole and heading in the same direction, in hopes of answering a question: how does the density of dung vary with distance from a watering hole? We hypothesized that density would be highest at an intermediate distance from the watering hole, given that animals may be more spread out further away from the watering hole, and that clustering close to the watering hole may be dangerous given the open terrain and presence of predators. We were almost immediately proved wrong. Almost every quadrat (125/126) that my group surveyed had poop present. While conducting this survey, it quickly became clear how the nearby boma impacted the landscape–the majority of the dung that we were able to identify came from goats, which the Masaai herd. However, another truth also emerged: that the Masaai and their herds in the area coexisted with diverse fauna. The poop that we observed ranged from tiny pellets the size of a pill to large clumps larger than my hand. While the results of our pilot study did not support our hypothesis in the slightest, they forced me to confront many of my preconceived notions of the destructive relationship between human settlements and animal richness and abundance. The Masaai boma did not eradicate animal usage of this natural oasis– just the opposite.
As the resident Alcelaphine expert (though definitely not a scat expert), I would like to take this opportunity to note that we observed dung possibly belonging to that of the Alcelaphini tribe. This is to be expected, given the water-reliance of the members of Alcelaphini. Animals like wildebeest and topi are rarely found more than 30 km from a water source, and their water-dependence is one of the reasons for the yearly Great Migration. Small seasonal water sources in the savannah like the one that we visited could provide a habitat for those Alcelaphini who do not migrate, such as hartebeest and topi. However, this is purely conjecture.
A very metal partially decomposed wildebeest skull at the watering hole
After staring at, smelling, and fiddling with poop for a few hours, we took a break and headed over to Shifting Sands. I was initially disappointed by its appearance–I was expecting something more along the lines of Great Sand Dunes National Park, and less like a heap of black sand sitting in the middle of the savannah. It looked more like a forgotten discard from a construction site than a curious natural phenomenon. But the more I learned about it, the more fascinated I became. The sands are mildly magnetic, causing them to stick together in their distinct crescent moon shape. There were markers leading out along the dirt road, marking their location in previous years. The 2023 marker lay more than twenty feet up the road, showing the great shift of the sands with the prevailing winds. We lounged on the sands for a while, Anna attempting to sled down the short slope while Dr. Solomon and Kamden befriended a group of Masaai children.
Just chillin on the sands (photo by Scott)
The afternoon was a routine that I’ve grown to love: lunch at Olduvai, followed by chatter and a friendship bracelet making frenzy. A stop at the Olduvai Gorge Museum for student presentations, then more efforts by Dr. Manuel to convert us all into teeth people. We spent hours examining the teeth that we collected yesterday and comparing them to museum collections to recreate the fauna populations present in the 1.5 million year old gulley where we’d found them. Fun fact: the most abundant bovid tribe in the gulley was Alcelaphini 😉 Using the population census that we developed (see also: taphonomic bias, blog day 10), we were able to ascertain (with great assistance from Dr. Manuel) that the gulley was a slow moving stream surrounded by a very open savanna habitat. This deduction was not just interesting, but mind boggling: the teeth people were able to conduct a forensic analysis of a habitat from OVER A MILLENNIUM AGO using only our bags of molars and incisors. Not only that, they were able to show us AN ILLUSTRATION of that habitat. Wow.
Still picking the sand out from between my teeth,
Rose
P.S. A limerick for my loyal readers:
Counting poop and playing in sand,
Learning about this lovely land,
I found some good bones,
Want to give them all homes,
But alas, they are contraband!
