Category Archives: Tanzania

Monkey Business

The last six months of my life have been consumed by red-tailed monkeys. I only spent ten days each month with these monkeys, but my red-tail research involved 14-hour work days. I woke up, ate breakfast, and hiked to wherever the monkeys slept the night before. I was with them from dawn to dusk, inputting “feeding scans” into a tablet every 15 minutes and collecting samples of new plant species that the monkeys consumed. I left at 7pm, after having been with the monkeys for 12 hours, to make the trek back to camp. After a quick shower and dinner, I pressed the plant samples of the day, and finally, crashed for some much-needed sleep before repeating the process the following day. My work with the red-tails resulted in me being given a most fitting nickname: Kaka Kima. Which means “brother red-tail monkey” in Kiswahili.

Even though I never expected to be doing a feeding ecology project on primates, least of all red-tailed monkeys, I found the work very enjoyable. The monkeys hung out in beautiful areas, sometimes near stunning waterfalls, and ate such a variety of fruits and plant parts that I felt like I was on a never-ending scavenger hunt for plant samples. Over the course of my six months, I collected and pressed over 150 plant samples to send to a botanist in Dar es Salaam (the capital of Tanzania). The feeding scans amounted to approximately 2,000 data points which will be used to determine dietary trends within this population of monkeys. The primates living in this area are unique because they live in a savannah-mosaic environment consisting of strips of forest surrounded by miombo woodland and savannah habitats. Red-tail monkeys are typically found and studied in rainforest habitats. The field site where I have been doing my research (Issa) is home to the only long-term study of red-tail monkeys in a savannah-mosaic environment. And the feeding ecology project will be the first to determine the dietary adaptations of this species to a savannah-mosaic environment.

Red-tails are known to eat a variety of fruits, flowers, leaves, insects, occasionally mushrooms, and very occasionally meat, such as small birds. One of the obvious trends I have found in the red-tail diet at Issa was a love of mushrooms. At other field sites, mushroom consumption is quite rare. But here, when the mushrooms begin to pop out, the red-tails go into a feeding frenzy. They race to the ground, grab a mushroom, and scamper back into a tree clutching their prize (often bigger than their own head).

The monkey antics can be endlessly entertaining. Nevertheless, even the most interesting work can become a bit monotonous if it done for 12 hours a day. Especially, because unlike what is often portrayed in nature documentaries, nature operates very slowly. Exciting events like inner-species encounters and new births do not happen every other day. Most days nothing out of the ordinary happens. But after six months of field work, rare and exciting events do tend to add up.

The two times I ran across predators happened during red-tail monkey follows. Both times, the monkeys alerted me to predator presence long before I caught a glimpse of the animal. The first predator encounter was with two lions – detailed in a separate blog. The second was with a leopard. When the monkeys alarm called, I immediately knew a predator was close by (it sounded just like their alarm calls during the lion encounter). The only question was what kind of predator. I was on the outside of the forest and watched the monkeys all congregate in one area, look down, and vocalize as loudly as they could muster. Finally, I caught a glimpse of a long tail, and moments later the field assistant I was with noticed a leopard’s face looking up at him about 20 meters away. The leopard had no desire to be near us, or the obnoxiously loud monkeys (predators rely on stealth to hunt their prey), and disappeared back into the forest in the opposite direction.

During another red-tail monkey shift, I almost stepped on a python longer than I am tall. This time though, the monkeys were not close enough to notice the snake so there were no warning calls for me. Luckily, the python had recently eaten (it had a large lump in its midsection) and was interested only in moving away from the bumbling human.

One of the coolest red-tail moments I witnessed was a group of subadult and juvenile red-tails leaving the trees to play in an ash-strewn landscape just outside the forest. The miombo-woodland and savannah habitats that surround the forests often burn during the dry season due to the extreme heat and dryness. This of course turns many fallen trees into ash. The monkeys took full advantage of this opportunity. They tumbled through the ash and threw it into the air like they were kids playing in the first snow of the winter. (for a short clip of their ash party, click here)

The terrestrial behavior of the red-tails at Issa is another unique aspect about this population of monkeys. The subadults and juveniles frequently leave the trees to play on the ground. And monkeys of all ages leave the trees to rest, travel, forage for food, and sometimes even to engage in grooming sessions. Terrestrial behavior of arboreal monkeys is quite rare, so I decided to collect data on this unique behavior. I gathered four months of data on terrestrial behavior on the two groups of monkeys and hope to publish the results if there is enough data to work with.

The 14-hour monkey days not only provided me with multiple data sets, but also provided ample opportunity to learn and practice Kiswahili. Thankfully, by the end of my six months, I was mostly conversational when it came to “in the field” Swahili – because I ended up needing to train a new field assistant to collect my feeding data for the next six months. Luckily though, he could speak some English, so whenever I didn’t know how to explain something in Swahili, I could usually communicate in a broken mix of Swahili and English and get my point across. Most of the field assistants knew a little English, some knew none, and one was fluent. Regardless, friendships were formed. And communication and attempts at conversation were typically full of laughter (and sometimes charades) and were one of the highlights of my time in Tanzania.

I will sorely miss my spending time with my Tanzanian friends, watching red-tails play wrestle on the forest floor, collecting new plant samples, and learning new Swahili words. Of course, field work is rarely glamorous, and I can’t even count how many times I was peed and pooped on, or had to army crawl through dense thickets of lianas or lost the monkey groups during a rainstorm. But for me, the hardships were a small price to pay for living out my dream of studying African primates, forming cross-cultural friendships, and learning a new language.

Of Monkeys and Mothers

Most mammalian mothers show maternal care unrivaled by the rest of the animal kingdom. Primates are no exception; parental care and offspring dependency is often extended longer than other mammals of the same size. In group living primates, the high ecological price of parenting (due to the energy required to produce the offspring and milk, increased vulnerability to predators with a dependent infant, etc) often results not only in an insurance that one’s genes will continue on, but often strong mother-offspring affiliations throughout their lives.

The topic of maternal (and paternal) care is a strong interest of mine and I hope, at some point in my life, the opportunity arises to further explore and research this area. But for the time being, swamped as I am with other research projects, I have consigned myself to simply photographing mother-infant pairs whenever possible.

Chimpanzee parental care is fascinating, but unfortunately, I’ve observed few interactions and taken even fewer photographs (but see Chimp Culture for a photo and brief description of a mother-infant observation). Therefore, this blog is simply an excuse to share my favorite photographs of monkey mothers (baboons and red-tailed monkeys) as well as some absurdly cute infants and juveniles.

First the red-tails:

And now the baboons:


Chimp Culture

Ask a cultural anthropologist if chimpanzees have culture and your answer will likely be “heck no – humans are the only species with culture”. However, ask a physical anthropologist and your answer might be a bit different. Physical anthropologists (also known as primatologists) often define culture as behaviors that are unique to a community of organisms (like chimps). Many of these behaviors can be observed being taught from adults to infants or juvenile.

Chimpanzee communities are known to exhibit community-specific behaviors. Some communities even exhibit dietary differences despite having access to similar food sources. Whether or not this is culture is up for debate.

I have been privileged to spend almost half of each month following the chimps here at Issa. I’ve witnessed two “cultural” behaviors. I’ve also observed many of the fascinating behaviors discovered by Jane Goodall in the 1960s that changed how we view humankind and one of our closest living relatives (don’t forget about bonobos being just as closely related to humans as chimpanzees).

I saw my first “cultural behavior” during one of my first chimp shifts. It is known here as a “grooming hand clasp.” Chimp communities often have specific methods of grooming that are unique to their community. The grooming hand clasp is performed when two chimpanzees each raise an arm to the sky and clasp each other’s hands, while one individual grooms the other. It is a very endearing behavior.

The second cultural behavior I have observed is “termite fishing.” It is unknown why some chimp communities will termite fish while others do not, even if termite mounds can be found in their home range. However, termite fishing is one of the behaviors that forever altered the way we view animals. Chimpanzees were the first species other than humankind observed to use tools! They fish for termites by stripping a long, pliable piece of bark from a sapling or branch and sticking it into a termite mound. Termites grab onto the “threat” with their mandibles (pinchers) and are pulled out of their mound and promptly consumed. Termite fishing starts at the beginning of the rainy season – which is also when termites begin their reproduction cycle of the year – and ends a couple months later.

Along with these cultural behaviors, the chimps at Issa exhibit many other behaviors and characteristics that make them so unique.

Some are quite intimidating to witness. Which is the point… Chimp “culture” is very male dominated. And to show their dominance, males will perform showy displays of strength. This can involve throwing their strength upon small trees to bend and snap branches, or even carrying and throwing branches at other chimps. Usually accompanied by loud screams from any chimps in the vicinity, the whole scene can be a bit unnerving if you’re close by. Especially unnerving is when male chimps saunter toward human observers and sit just a few meters away staring at us (we have one chimp in particular that will do this). Eye contact is often taken as a threat, so we avert our eyes and try to look extra small when this happens. Occasionally a male chimp will even run toward people (sometimes with their backs turned), slapping the ground or tree trunks as he goes along before swerving off in a new direction.

Chimpanzees, like most species, fear people. For us to study chimp behavior they have to be slowly habituated to the presence of humans. Lucky for me, the chimps at Issa (after several slow years) are reaching the end of their habituation process and beginning to ignore humans for the most part. The exception is the male chimps that occasionally test the nerves of the human observers.

The newly habituated chimps allow us to observe some of the subtleties of chimp behavior. Things like large adult males gently playing with a tottering infant. Or a mother tapping her back as she walks past her infant to tell her child to hop on.

Chimpanzees also display the artful skill of making nests. Yes, one of our closest relatives makes nests, like a bird. They bend a multitude of leafy branches high up in the trees to make a new nest each night. Sometimes they even make “day nests” when they have an extra lazy day and want to be more comfortable. I’ve even seen a subadult male chimp display his creativity while he was lounging on a rock. He looked at his surroundings, grabbed a nearby sapling, pulled it down so its leaves covered his rock, and promptly laid back down.

Although the chimpanzees here are habituated, it is still quite easy to lose track of them when they travel quickly along the mountainsides filled with lianas and thickets. When we lose them, we rely on vocalizations to find them again. It is rare that a full day goes by without a chimpanzee group starting a chorus of pant hoots and screams. Sometimes they vocalize seemingly to just hear their own voices. Sometimes it’s to exchange vocalizations with other groups within their community across valleys. And sometimes they vocalize during or after a rain, while shaking branches or charging around on the ground. These are known as rain displays and you can almost feel the exhilaration and awe of the individuals during these experiences.

The larger the group, the more often they send their voices echoing throughout the valleys. We have approximately 26 individuals in the community here and they form smaller groups to forage and travel together. Although it is somewhat rare for all the individuals to travel together, it does happen occasionally. On one of these occasions, we lost the chimpanzees briefly as they ran up the side of a mountain while vocalizing. When we reached the group a few minutes later, they had a dead bushbuck (a hoofed deer-like animal) up in the trees. They had successfully hunted! A large male carried his prize through the treetops and then back on the ground. Various individuals, even a mom and her infant, clutched pieces of meat in nearby trees. Eventually almost the entire community gathered around the kill, sharing meat with every individual, from the biggest male to the smallest infants.

If you ask me, chimpanzees have culture. Maybe culture isn’t the right word… It’s impossible not to view other species through the lens of our anthropocentric worldview. But I feel something akin to culture during rain displays. I see it in the grooming hand clasp. And I find it in the leftover tools at termite mounds. And it is an extraordinary privilege to have fleeting glimpses into the world of one of our closest living relatives.

A Day in the Life: Lions and chimps and monkeys, oh my!

This is the story of the craziest day I’ve had so far in Tanzania.

It was my fifth consecutive day with K1, a group of more than thirty red-tail monkeys. After four, fourteen-hour days behind me already, I was struggling to keep up with the group from the beginning of the day.

The monkeys were already making things difficult that morning, traveling higher and higher up the slope of Mchungwa valley, entering thickets impassible by humans, and spreading out so much that it was impossible to see more than a few monkeys at a time. Just as Judi, my field assistant for the day, and I sat down next to a thicket, thinking the monkeys were finally going to settle down for a few minutes, chimps materialized just ten meters away. We hadn’t heard them coming. Nor did they make any sounds as they climbed a tree, watching us as they settled into comfortable sitting positions. There was a female, her infant, and a juvenile. A bit further down the slope, we saw even more chimps popping up into the trees. By this time, most of the monkeys had melted into the tangle of vines covering the upper portions of the mountainside. Although chimpanzees rarely consume red-tailed monkeys (in fact – we have yet to observe the chimps preying on red-tails at this study site), our monkeys do not take any chances.

Along with the arboreal chimps, we could hear a few individuals screaming and running through the underbrush below us. So, there we were – stuck between a group of chimps and the impassible thickets. There was nothing to do but wait until the chimpanzees had moved further away so we could slide down the slope and try to find our way back to the monkeys, wherever they had fled.

In the short period of time Judi and I were stuck, unable to travel, the monkeys covered a long distance. It took us another three hours to find them, travelling so far along the valley that the mountainsides gave way to a plateau. Jubilant at finding the monkeys again, we got back to data collection. For me, that meant recording and collecting plant samples of the food items the monkeys were consuming. As I stopped to collect a sample of a new woodland plant that a monkey had nibbled on, I lost the group momentarily.

When I returned to the group, I heard a chorus of chirping (the monkeys make very bird-like vocalizations) and scuffling in the underbrush. Stooping down to get a better look, I saw a group of at least eight monkeys surrounding an owl. A few monkeys simultaneously jumped on the owl, while others vocalized and watched while perched on low hanging lianas. Then a monkey darted out and pulled the owl by its wing along the forest floor. This all happened multiple times while I frantically tried to video record and narrate the frenzy of activity. The owl was pulled into a nearby dried up river bed and the monkeys hovered over it for a few more minutes, shaking lianas above the bird but producing fewer and fewer vocalizations. Finally, the monkeys bounced away, starting a game of chase on the ground. I couldn’t get down to the riverbed without navigating a circuitous route to avoid thorny vines. So, by the time I made it to the owl’s previous location, the bird had disappeared. Lucky for the bird, this meant it survived the mobbing and flew away. Unfortunately for me, the bird’s quick disappearance meant I couldn’t get a good enough picture to identify the owl species.

(Monkey-avian interactions are quite rare, so we are hoping to publish this anecdote as a “short communications” paper in a primatology journal. And after looking through some bird books back at camp, we think the owl is an African Wood Owl.)

The owl mobbing was unique and strange enough, but nothing compared to the rest of my day.

The monkeys had settled down a bit, so we took a seat on the forest floor. Judi had just broken out her Tupperware for a late lunch when the alarm calls began. The handful of monkeys that were wandering the forest floor shot up into the trees and the entire group started traveling quickly downriver – all the time maintaining the highest intensity alarm calls I’ve ever heard from them (their alarm calls – like their other vocalizations – are also very bird-like). The constant chirping drowns out all other sound as I rushed after them, stumbling through the rocks of the dry river bed while trying to follow the movements and sounds above me.

Then they stopped.

I looked around me, expecting to see a predator of some kind. Maybe African Wild Dogs, maybe a Jaguar. Or maybe just a bumbling bush pig that the monkeys mistook for a threat. But the intensity of the alarm calls coming from high in the trees put me on edge.

Then I saw one, then two, female lions cross the river bed a mere thirty meters ahead.

They didn’t look at me. They just plodded across the stones and disappeared, almost before I could even register what just happened. Lions hadn’t been seen in this area since 2014. Also…. those were FEMALE lions! The hunters! Even though the lions didn’t look at me, they had to have known I was there – either by smell or the noises I made stumbling through the rocks. What if there were more? The growth on either side of the river made it impossible to see what could be hiding in the foliage. I quickly used my radio to call Judi (who in the midst of her lunch hadn’t been able to pack everything and keep up) and told her what I saw and that she should probably stay put. I would make my way back to her. My heart pounded and my legs were weak as I staggered back to her. We met each other wide eyed and suck in more air than normal as we discuss our game plan. As we crept along the river bed, towards the monkeys but also possibly towards lions, we exchange nervous looks. It’s not like we were provided with lion defense training. As we made our way outside the forest and discovered no hidden lions, we laugh in relief.

“Almost any organism around lions might be a potential prey item, and for people to think that they are an exception is folly” says Luke Dollar, director of National Geographic Society’s Big Cats Initiative. “I would imagine that every other primate that co-exists with big cats is acutely aware of the position they hold relative to the top predators of the world.” Read more here.

Lions or no lions, we still had to catch back up to the monkeys.

And they were making their way down a strip of forest sidling Moporomoko Kubwa – translation: “big waterfall” (also dried up until more rains fall). Which meant we had to climb down the steepest trail in the study site – a trail that I’ve fallen down more times than not. With adrenaline still pumping, we cautiously made our way down the trail – only to find that the monkeys were nowhere in sight. Two hours spent searching the forests, up and down slopes – once again made difficult by the tangles of vines and thorny vines – yielded no monkeys. Which meant a climb back up the Moporomoko Kubwa trail in case we misread their traveling intentions. Then halfway up the trail, a downpour began. We were soaked before we could make it to the top to don our raingear. Chimp vocalizations began echoing through the surrounding woodlands and forests and we knew the chance of finding the monkeys had dropped to zero.

Red-tailed monkeys don’t like the rain and they don’t like chimps.

Although our days don’t normally end until 7:00pm, at 4:00, on this last follow day with this group, we didn’t feel bad about heading back to camp a bit early. After a 45-minute hike in a downpour, we crashed at camp. We tell our story. Everyone is shocked. Some are a bit nervous. And almost all the foreigners are jealous about our experience and excited about the possibility of having lions back in the area.

My fingers were so numb from the cold rain that it took about 30 minutes of clutching a mug of hot tea before I could text my supervisor the news of the day. With too many details to fit in one text, I basically just bullet point the day. The next day I typed everything out – as scientifically as possible.

A month and a half later, I’m finally typing out the narrative form. Lion encounters and the owl event are rare occurrences here (although there were several lion sightings over the course of the next week – I even saw some lion prints and scat a week later). But the rain, chimps, and treacherous hiking are very typical indeed.


I hope this paints a picture of how unexpected life in the field can be.


Karibu Tanzania

Karibu Tanzania. Welcome to Tanzania. These were the first words to greet me as I landed in the capital of Tanzania (Dar es Saalam); the first words to greet me after my puddle jumper landed on the dirt runway of Kigoma (a quaint town in eastern Tanzania, on the edge of Lake Tanganyika); and the first words to greet me as I arrived at the GMERC camp.

From the moment I stepped onto the dirt runway in Kigoma, I felt right at home (not so much in Dar – cities are not my thing). The researchers who picked me up were warm and welcoming. And the rest of that first day was spent at a beach, watching waves crashing on the shore (Lake Tanganyika is the second largest and second deepest freshwater lake in the world), eating baked potatoes and avocado salad as the sun set and the stars lit up the night sky.

The next day, after a whirlwind of shopping at the market, 6 people and 2 weeks of food and supplies for the 18 or so people at camp were packed into a Land Rover, and we trundled off to the bush. Three hours later, we left paved roads and dirt roads behind and were bouncing along a path so narrow we had to tuck in the side mirrors. A couple of broken eggs later (the stack of egg trays was perched on my lap, so this was slightly unfortunate for me) and we had arrived at camp.

The cooks, field assistants, and other researchers greeted me with “Karibu Tanzania” and “Karibu Campi.” On my tour of camp, when we were at the highest peak, I was greeted by panthoots and screams from the resident chimp community echoing across the surrounding valleys.

What a way to be welcomed to camp!

Camp Life

Immediately, I was comforted by the prospect of making a tent my home for the next 6 months. An added bonus: my tent contained a mattress and was large enough to actually stand upright! What luxuries! The prospect of bathing in a river seemed like fun as well until I gave it a go that first afternoon. It brought back too many memories of ice baths during track and cross-country season. From that day forward, I brought a cup to the river. No more submerging any part of me again.

Even though camp is only a few miles from a fairly well-traveled dirt road, it is truly in the middle of the bush. One of my first afternoons at camp, someone saw a black mamba looped around a branch next to the river while they were bathing. Recently, I almost stepped on a puff adder on my way to the toilet. Numerous other reptilian friends (ones with legs) sun themselves on the rocks at camp and I can’t even count how many days I’ve had to maneuver my way through a troop of baboons on my way to bathe. Blue duikers come sniffing around our tents at night. Packs of hyenas whoop to one another right outside our tents at night and occasionally we hear them near camp on our way out into the field in the morning. Leopards have been sighted traveling right outside of camp. And one recent morning, all of camp was awoken by chimps vocalizing 50m from camp at 5:30am.

The food at camp – consisting almost entirely of beans and rice – made for a rough adjustment period at first. But weirdly enough, two and a half months later, I’m actually beginning to crave beans when I get hungry. A good thing since beans are a staple of every meal! For dinner, we get a piece of fruit or vegetable. And instead of rice we either have ugali, potatoes or plantains, or (about once a week) mini loaves of bread or two pieces of chipote (circular flatbread). On bread nights, we typically get a hard-boiled egg. The best dinners are the bread nights after someone takes a trip to Kigoma because then there’s often the treat of a half an avocado.


The landscape when I arrived was unlike anything I’ve seen before. The rocky mountainsides were covered in sparse, bare trees and tall yellow/dead grass, while the valleys and plateaus contained thin strips of dark green forest. For the first month, fires were frequent, and we often hiked through ash and the smoldering trunks of fallen trees or branches. Two months later (after some heavy rains) and almost everything is now green. The woodlands covering the slopes and most of the plateaus sprouted leaves almost overnight and green grass is now poking out among the leftover dead grass.

This type of landscape is called a savanna-mosaic environment. Aptly named, because it is truly a mosaic of habitats. Fifteen-foot cacti grow alongside strips of lush green forests. And after more rains come, swamps will form in patches amongst the forests, woodlands, and grasslands. It’s difficult to become bored of this ever-changing environment.

My first day in the field I found myself trekking over 10 miles, sliding down rocky slopes, hiking through valleys, and scrambling up mountainsides. We were following chimps we had spotted from across a valley, but once we had caught up to them, we realized these were unhabituated chimps – not part of the semi-habituated chimpanzee community. Most of the other chimp days have been much more successful, although they often still involve lots climbing and sliding down slopes.

Some of my days entail following around a troop of baboons – the same troop that is often found wandering through camp or foraging by the river where we bathe. Other days consist of random shifts with some of the various projects here at Issa – phenology, termite mound research, and trail camera maintenance.

My own research, however, is on red-tailed monkeys. I follow two habituated groups of this species, each for 7-10 days every month. My main project is studying their diet. This species is typically found in rainforest environments and thus, the only dietary research conducted on this species has been in that type of habitat. Studying their diet in a savanna-mosaic environment will help extrapolate their dietary adaptability and to what extent they exploit the different habitats in their home ranges. For me, this means lots of group scans, collecting (and pressing) lots of plant samples, and trying to learn as many plant species as possible. This also means five consecutive 14-hour days of fieldwork for each group to collect the amount of data I need. Although I never expected to be doing feeding ecology research, I am loving this work. It’s exciting to collect a new plant species that the monkeys have consumed (almost like a treasure hunt). And it’s quite enjoyable to learn, and sometimes try, the numerous fruits that the monkeys eat (although more on that later).

I already have so many stories and experiences from these past two and a half months that I can’t possibly include them all in one blog. But I will try, in between the 14-hour days chasing monkeys, to type up these memories and share them.

Asante sana (thank you very much) for keeping up with this journey of mine!