10 July 2013: Mbandaka, DR Congo. Today I am providing two posts with photos because I was finally able to get ahold of an internet connection and charge my computer. The package from the satellite company arrived, and I am hopeful I will be able to use the new charger to post from the middle of nowhere for the duration of the expedition. I have also updated the older post about the bonobo forest with some photos.
When looking at the size of the font associated with the regional capital of Mbandaka on a map, it is by far the largest city in Equateur Province, so I had high hopes for a break from the fieldwork in a reasonably comfortable hotel with decent food. That expectation is not unreasonable in the regional capital of Bukavu in eastern Congo, where I have worked during my previous six expeditions to Congo. But alas in Mbandaka, it was not to be. The nicest hotel in town (the Benghazi) had no internet and there was no cyber café anywhere near it, so I had to settle for something much more modest. As I explored the city, I quickly realized that many mosquitoes are active during the day, a highly unusual annoyance, even for Congo. Mbandaka can best be described as a large town, and although there is an airport for regional flights within Congo, I could not see any other major amenities associated with a large city. The only other sign that the place is larger than the average Congolese town is the presence of foreigners, including Indian shopkeepers, European UN workers (dealing with the aftermath of a civil war in neighboring Central African Republic), and Chinese with unknown business dealings.
The striking thing about Mbandaka, however, is that it must have once been a major city. Very nice, spacious Belgian houses with distinctive arches, chimneys and carports are everywhere, as are entire city blocks with storefronts, churches, factories and other major buildings. Based at the confluence of the Congo and Ruki rivers (and not far from the Ubangi river bordering Congo Brazzaville), Mbandaka would have made a convenient business center for ivory, rubber and other commodities coming out of the jungle and destined for Europe during the colonial era. Because the only reliable internet café in town does not allow its patrons to use their own computers, I also had the opportunity to visit the famous Eala Botanical Gardens at the edge of the city, where a regional wildlife office has a solar-powered internet connection. The gardens have plants and trees of all kinds from tropical areas all over the world, and it also was a major tourist site and research center during the colonial era.
But I digress… I will pick up the story where I left off at Isongo.
After an all-day drive through the remnants of forest along the road heading north from Isongo, including an hour-long adventure to extract our truck from a roadside ditch and kickstarting it, we reached Bikoro just before dusk. It took us an hour to find a restaurant where we could get something to eat, and I was treated to an ice-cold grenadine soda. After weeks of lukewarm water, it was an indescribable pleasure to feel the cool liquid chill the inside of my body and rehydrate me after the long journey. The restaurant’s specialty was bushmeat, including antelope and monkey, but I refused to allow anyone to eat that and we all had fish from nearby Lake Tumba. It was delicious, and I was so hungry after weeks of one rice-and-beans meal per day that I had two plates.
Not wanting to deal with our problematic truck any longer than necessary (it had to be kickstarted again several times before we could leave the restaurant) I decided to look for a place to set up our next basecamp immediately. Normally this wouldn’t be a good idea in the dark, but Chifundera had worked in the area a few years before, and he said there were nearby pygmy villages where we could have the possibility of soliciting their help to find animals and work near the forest. The place he had worked before was too close to Bikoro for my taste, but a few kilometers to the north, we found what we were looking for at the village of Npenda. Although the vegetation immediately flanking the road was heavily damaged by human incursion, I could see and hear good forest just a little bit deeper, and we decided to set up our operation there. It never ceases to amaze me how Congolese people from every tribe we have ever dealt with are amenable to the unannounced arrival of strangers into their village, even in the middle of the night, and the pygmies of Npenda went a step further by helping me to set up my tent. The next morning when I casually remarked that their “toilet,” an open pit with a few withered fronds of vegetation surrounding it, did not afford much privacy, they immediately constructed a new shelter around it that was large enough for my taller body to fit comfortably.
When we finally got around to explaining why we had come, everyone seemed willing to help with our endeavor, including the children who graciously caught a few treefrogs for us. One of those frogs turned out to be Hyperolius phantasticus, a species with a distinctive black belly that I had never seen before. If someone happened to kill a snake, a practice that all Congolese seem to do across the country, they brought it to us smiling. After a heavy rain, several burrowing lizards (Melanoseps occidentalis) decided to crawl to the surface, where the pygmies happily collected them for us. On all my previous expeditions, I had found only one Melanoseps that happened to crawl under the chair where I was working, but at Npenda, over a dozen were found in one day. Most exciting for me was the presence of Holaspis, a colorful genus of lizard that has the rare ability to glide from tree to tree, probably as an adaptation to escape predators. Their heads are flattened, the fringes of the body, tail and even fingers have little folds of skin to create lift, and other adaptations have made the lizards remarkably light, all essential qualities for them to glide. Below is a photo of one of the Holaspis.
Some of the more overzealous pygmies brought us animals we weren’t looking for, including mouse-like creatures with bushy tails, insects of all kinds, fish, worms, and even a bizarre creature called a pangolin. The pangolin is an arboreal mammal that occurs in forests of Africa and Asia, and it has a distinctive elongated body with a pointy snout, long and curved claws, and what looks like a suit of armor in the form of shiny protective scales that cover its body. The pygmies had to climb into a tree to capture the meter-long animal, which undoubtedly ended up in someone’s cooking pot after we took a few photos of it.
When we were able to enter the forest, we found that it was a swamp forest, not too different from the one at Mai-Ndombe, but the trees were of a different species and the ponds were much larger, making movement very difficult. That aside, we found several interesting frogs, including another toad that is likely to be new. But the most spectacular find came when I least expected it.
Because we were finding so many animals, I spent most of the week-long stay at Npenda taking notes, photographing animals, taking DNA samples, and processing specimens. One afternoon as I was immersed in my work, Aristote showed up with uncharacteristic excitement to show me a very large tail of a snake. It was yellow with distinctive black edging around the scales—a mamba. Renown as the most dangerous snake in Africa, there are several species of mamba in sub-Saharan Africa, including the terrestrial black mambas and the arboreal green mambas. Depending on the species, they can be quite long at over 3 meters, they are considered to be the fastest snakes on the planet, and their venom is absolutely deadly. Depending on the species, the venom can either shut down all muscle function (causing death by asphyxiation) or cause deadly internal bleeding. Black mambas in particular are legendary for their aggressive behavior when surprised or cornered, but relatively little is known about the green mambas, and least of all about Jameson’s mamba, which occurs in the forests of the Congo Basin. I immediately experienced a surge of adrenaline when I realized that I was holding a mamba tail.
When I asked what had happened, Aristote explained that someone had seen the snake moving at the edge of the village, and had dared to attempt to kill it with a machete. The snake had moved so quickly to escape that all the man had to show for the encounter was the tail. At least I would have a DNA sample that I could use to compare this animal to a juvenile I had found killed by a car on the opposite side of the basin in the Ituri forest in northeastern Congo in 2009. But Aristote’s rendition of the snake encounter turned out to be false. A few minutes later a man arrived with the mamba’s head, and I got the full story. A couple had been cultivating a field at the edge of the forest when the woman saw the snake. She alerted her husband, who used a hoe to inflict a crippling wound to the spine of the animal. The woman then finished it off with a blow to the neck with a stick. The woman thought of selling the spectacular snake to us, but her husband refused, because the mamba is considered a delicacy. News of the kill spread quickly, and Chifundera and Aristote could only watch helplessly as the pygmies cut up the mamba into bite-sized morsels, which they grilled and ate with relish. It took all of Chifundera’s charisma to convince them to give us the head, which they were planning to destroy for some form of traditional medicine. We shouldn’t scoff at the pygmies for this, because several useful biomedical molecules have come from snake venom, including mambas, and further research is needed to understand how their venom might be beneficial to human health. Below is a photo of the mamba head and tail; to provide a sense of scale, the mamba’s head is as long as a man’s thumb. Based on the size of the tail, I estimate that the mamba must have been at least 2 meters long.
Below is another snake photo that I am providing as part of the cybertaxonomy project. The total length is more than a meter, it is an arboreal species, and like the mamba, we know very little about its venom.
On my last day at Npenda, I took a break from my work to observe a ceremony celebrating the birth of a child in the village. All the women and children were singing and dancing, and four girls (ranging in age from 8 to 12) were dressed in traditional pygmy attire. Unlike everyone else, they didn’t sing, but they wiggled their bodies suggestively as everyone danced around them. Below is a photo.
When it came time for us to leave, the pygmies watched solemnly as we packed up our gear and loaded it onto a dilapidated truck that Chifundera had found in Bikoro to transport us to Mbandaka. When I got inside, I noticed that everything had been stripped away, including my seat belt, the door handle, most of the dashboard, and all material that had once covered the steel frame of the truck. Such is Congo. After a few seconds I noticed a hideous odor emanating from somewhere inside, but then realized it was me—I hadn’t showered in several days and was looking forward to doing so in the city. Of course several people had to push the truck to kickstart it, and when the motor fired up, it was intensely loud because the muffler had obviously been taken or was so full of holes it had been rendered useless. As we started to roll away, the pygmies were smiling, and all the children yelled and ran after us until they couldn’t keep up. I am sure that if the team ever returns to Npenda, we will be remembered.
Fruit Bats Are Terrible Singers
4 July 2013: Isongo (a.k.a., Isanga), northwestern shore of Lake Mai-Ndombe, DR Congo. In contrast to our previous boat trips, the voyage from Kutu to Mpote-Emange was enjoyable and without incident, at least until our arrival. As we turned north and entered Lake Mai-Ndombe, I noticed the water changed from light brown to the color of strongly brewed tea, and as the bobbing bow of the boat churned the water, it seemed as though we were passing through an ocean of root beer. In Lingala, Mai-Ndombe means black water, and I would soon discover that the water’s color was a result of a liberal amount of sediment and other particulate matter (it clogged my water purifier repeatedly). After passing a modest logging operation on the southwest bank, we saw few villages and countless miles of beautiful, pristine forest that came right to the shore of the lake. Eagles soared overhead everywhere, and in places the lake was wide enough that I couldn’t see the opposite side.
As we approached the town of Inongo, the closest thing to a town on the lake, I told Chifundera that I wanted to stop at a nearby village so that we could be close to the forest. After chatting with some local fishermen, we opted to set up our camp at Mpote-Emange, a village of about 100 people, just a mile south of Inongo. When we arrived, an elderly man took one look at me and exclaimed “ooh la la!” in French to express his surprise at seeing a white man there. Barefoot and nearly toothless, he used a walking stick to hobble around, and he wore the same red Cleveland Indians t-shirt every day for the week we spent there. In the Bradt Travel Guide to Congo, the author Rorison remarked that Congo is where unwanted American t-shirts go to die. Because most Congolese don’t speak English, they often have no idea what the shirts say or mean, and they are usually chosen for their creative artwork or cheap price. Often these unwanted t-shirts were discarded by their previous owners because they were not socially acceptable, and more than once I have seen clueless Congolese people donning shirts that have curse words or crude bodily functions. I couldn’t help but laugh when I spotted a stoic elderly woman wearing a graphic shirt that obviously originated from someone’s drunken spring break trip.
When we had a chance to enter the forest, we discovered that it was a freshwater swamp forest, evidenced by the “stilt roots” of the trees (see photo below), which are an adaptation to deal with waterlogged soil, improving structural stability and access to oxygen. Such forests typically flood part of the year, but our visit was in the middle of the dry season, so we were able to move around without sinking to our knees in mud and water. However, many places had large, stagnant pools of water that contained a diverse array of invertebrates (including plenty of mosquitoes), freshwater fish, and aquatic frogs. I surmised that during the wet season, parts of the forest likely flood and merge with the water of the lake. Within 10 minutes of arriving in the forest, we found what is likely to be a new species of Arthroleptis frog in the leaf litter.
At night, things became even more interesting, but only for amphibians—unfortunately we did not encounter a single reptile in the forest during the week we spent there. One of the focal taxa, or important animal groups of the project, is the genus Amietophrynus, commonly known as the African toad. I decided to work on this group a long time ago as a graduate student, and I am now close to publishing a major analysis of the DNA-based evolutionary relationships of these Central African frogs (toads are simply one family of frog, the Bufonidae). Why should we care about this? Toads are an ideal model organism to search for patterns (i.e., relationships from their DNA) that can help explain the ancient processes (i.e., geological history, climate change) that have affected ALL organisms living in the Congo Basin. Based on my preliminary data, what I thought was three widespread species of toads in the Congo Basin are actually more than a dozen “cryptic species,” which are species that are genetically distinct, but morphologically (i.e., color pattern, size, shape, etc.) very similar. Understanding this is important for multiple reasons, perhaps most importantly for conservation implications. If the newly elucidated species each have a small geographic distribution, then conservation measures must be changed to ensure that all of them are protected. From the scientific/intellectual standpoint, I now think the cryptic species formed in forest “refugia,” or little islands of forests that persisted when the globe’s climate became cooler during the Miocene about 10 million years ago. What is now one giant carpet of lowland rainforest from the coast of Gabon to eastern DR Congo was mostly savannah with a few forest refugia back then, and these refugia isolated populations of animals that can only live in forest, including the toads. Over time, these separated populations diverged from each other genetically, until eventually the genetic differences became so large that the populations became distinct species, often with minor morphological differences. This National Science Foundation project is helping to elucidate these concepts, and the surprising thing I am finding is that every field site I visit seems to have its own distinct species of toad! See the photo below for the toad at the forest at Mpote-Emange, which is likely a new species. Perhaps the Congo Basin had many refugia during the Miocene, and this project will help to examine that hypothesis.
One of the annoying things about my work at Mpote-Emange involved the pros and cons of my visit during the dry season. The lack of rain makes it easier to move through the forest, but some species of amphibians are not active. At this time of year, many trees shed their leaves, and few of the forest species produce any fruit. Luckily for the frugivores (fruit specialists), there is one species of tree that produces a delicious bounty of fruit at this time of year when it is needed the most. The fig tree (genus Ficus) produces golf-ball sized orbs of red fruit that are coveted by everything from monkeys to antelopes. There happened to be a fruiting fig only 100 feet away from our campsite, and I could actually smell alcohol from all the fermenting fruit that had accumulated on the forest floor. Because the tree was so close to the village, most animals wisely stayed away—all except one. Imagine a Chihuahua with wings and you’ll have a pretty good idea of what a fruit bat looks like. Because they can fly into the canopy of the tree, well out of perceived danger from predators, one particular fruit bat had no fear of feasting on the fruit every night. And what do you do once your belly is full? Call for a mate of course. I struggled to come up with a description of the call and decided on two somewhat complimentary analogies. It can be described as either a wheezing clown horn, or an amplified and endless game of ping pong that is repeated with rapid, maddening succession. Each night the bat started his calls about 15 minutes after sunset, and he did not let up for more than a few moments until he finally went to sleep (or got lucky) at about 4 AM. Even with foam earplugs, an invaluable thing in the racket of the rainforest, the bat’s incessant calling caused some restless nights.
After dealing with yet another transportation misunderstanding with the boat captain from Kutu that involved an entanglement with the local military and officials from Inongo, a judgement was made against us and we were forced to hand over $100 in fuel that we had hoped to use to get to the northern shore of the lake. Starting from scratch but wiser, we had to pay hundreds of dollars for the short boat ride to Isongo, a small town on the northwestern shore of the lake. My map called the place called Isanga, but perhaps names change over time, or it was a colonial error of transcription, a common problem with the names of Congolese villages and towns. Most of the people there were of the Bolia tribe, one of many Bantu peoples in Congo, but there was also a small population of pygmies. The latter group of people knew the forest well, and they helped us to get ahold of some reptiles, including several snakes, and a large burrowing lizard with a white head (genus Feylinia) that is usually found in the savannah. Even more unusual, it was found in a stream in the forest, and I am eager to examine its DNA upon my return to the USA to see if it could be a new species.
On the last day of our work at Isongo, some teenaged boys showed up with some dwarf crocodiles (genus Osteolaemus), which are considered to be an endangered species by the international community. The crocodiles’ legs were hogtied behind their backs, and their jaws were bound and attached to the tail so that their bodies formed a convenient purse for carrying around. In most of Central Africa, crocodiles, monkeys, chimpanzees, gorillas, and other endangered species are considered meat and nothing more, and in areas where there is no inkling of conservation measures, they are certain to be wiped out within a few years. The frustrating thing about the crocodiles is that they have not yet been studied thoroughly, and it is possible, even likely, that the dwarf crocodiles south and east of the Congo River are a distinct species. I contemplated that I am studying a fauna that will probably be wiped out by the end of the century, but at least my work will allow scientists of the future to understand what was lost. With that sobering reality in mind, we headed north to Lake Tumba after Chifundera pulled off a miracle by finding a truck after everybody said there was none to be had.