Thwack! I jumped at the loud splash on the water behind me. Twisting around in the boat, I found myself looking straight into the eyes of a teenage chimp, a leaf-covered branch in her hand. Defiantly, she smashed the branch onto the water again, letting us know that she wanted her share of the food that was being thrown from the neighbouring boat.
"That's Frankie," explained Michelle. "And over there is her son, Felix. You wouldn't believe that she used to be terrified by cameras."
Frankie had once associated the click of a photo being taken with the sound of a gun going off. Hardly surprising - as a baby she was found chained to a table on which the cut-up remains of her mother were being sold for bushmeat.
Frankie was one of the lucky ones - she now lives in the River Gambia National Park in conditions that replicate those of a wild community. The Chimpanzee Rehabilitation Trust, founded by Stella Marsden, took in its first orphan chimp in 1968 - an action that changed her life. As more and more confiscated or orphaned chimpanzees were offered to her, Stella needed somewhere to home them. Having tried to integrate them into the wild in Senegal, drought and aggressive wild chimps led Stella to seek a solution in The Gambia.
In early 1979 Stella brought her chimps to what was intended to be a short-term solution: the newly gazetted River Gambia National Park. As Stella's husband, David, told me over a beer on the evening I arrived in The Gambia: "Here we are, nearly 30 years later - and the temporary solution is still there!"
Sadly, during my visit David was on his own. Stella was diagnosed with cancer in early 2007; despite being a fighter, the cancer had spread and her condition deteriorated. When I visited in November she had just returned from radiotherapy in the UK and was intending to accompany me to Badi Mayo, the Trust's visitor lodge on the banks of the River Gambia. Unfortunately she was too poorly, so David met me alone to fill me in on her beloved chimps.
He talked me through Stella's upbringing in The Gambia and a British boarding school, and her early involvement with chimps: "It was one of those accidents of life. Her eyes were opened to trafficking as more and more were coming through. Many were going to end up in labs or at Spanish beach resorts. Whatever struck those ladies who deal with primates, she got struck!"
There have been many struggles along the way, but the 19 chimps that arrived with Stella have since grown to 85, some of them third generation.
I was now itching to get upcountry. My arrival in The Gambia had been a bit of a culture shock, the airport packed with eager holidaymakers attracted by the prospect of winter sun and beaches. "I can't wait to get these clothes off," confided the nice man next to me on my coach transfer. No, he wasn't being suggestive, just dreaming of lazing by his hotel pool.
I, on the other hand, was itching to pull out my binoculars as we passed a group of red colobus monkeys, just outside the airport car park. Fifty metres further on, a minibus of excited twitchers had already pulled up to watch a smattering of The Gambia's 560 species of bird.
A 45-minute ferry ride across the River Gambia the next morning was reassuringly West African. Dazzlingly dressed women walked on board, skilfully balancing bundles on their heads. A huge billy goat, legs tied together, had to be carried by four men, while a sheep bleated plaintively from under a luggage net on the roof of a bus. There was enterprise everywhere. I stocked up on toothpaste from one hawker, while others paraded garish watches, biscuits, cold drinks, radios and sequined bras.
It was the start of a long and frustrating journey upcountry to Badi Mayo. But, as I squeezed onto a small boat seven hours later, passing lush vegetation, mahogany and kapok trees, I finally entered the national park. The tents of Badi Mayo, my home for the next two nights, were spaced along the side of a ridge, each with an open-air shower - "but only the chimps will be able to see you."
Michelle, a vet from Ireland, was running Badi Mayo; she explained that the chimps live on the three largest islands in the park. Island 1, facing us, housed two different groups, while Islands 2 and 3 supported one group each. I was just in time to join a boat trip to watch the feeding of the chimpanzees on Island 2. That group - 17 adults and several youngsters - receives supplementary food once a day, mainly to offset competition from baboons. Gambia's baboons are seen as a pest by farmers, and are therefore persecuted. During one big hunt a few years ago, a group of baboons had swum to the island; they'd been there ever since.
Sure enough, as we rounded the island and got our first view of some chimps - ignoring us as they tucked into the pumpkins that had been thrown to them - we were also very aware of the baboons on the periphery, attempting to steal food.
Michelle pointed out the alpha-male chimp. Another adult male, Hesus, sat a respectful distance away. Several females and their offspring were in the trees, while Frankie made her presence known in her own inimitable way.
We moved off to the other two islands. Here, the chimps are given food every two days, as much to keep an eye on them as for nutrition. Michelle and Bubacar, the main guide, talked me through the chimps' stories. For example, Jumbo, the alpha male on Island 3, was rescued from Spain; there he'd been a photographer's chimp, wearing pants and smoking a cigarette.
Before we got too sentimental about the chimps, Michelle pointed out that their society can be brutal. The alpha male of one of the groups on Island 1, Gorko, had been deposed by a male called Jallow. Having been pushed out, he was then attacked whenever the other males came across him, and had suffered some horrific injuries. He hadn't been seen for a couple of weeks and the worst was feared.
A fellow guest was disappointed that we were not allowed any contact with the chimps, but Michelle pointed out that it would be a bad idea on safety grounds: "They have no fear of humans," she explained. It would also be potentially dangerous for the chimps, as infections could be passed on. And wouldn't it be missing the point of letting them live as wild?
The next morning I got to witness how the locals benefit from the presence of the chimpanzees. After breakfast, my chariot literally awaited - a good-looking grey horse pulling a simple wooden cart arrived to transport me. This was Elliott, one of several rescue horses that live at a nearby centre run by The Gambia Horse and Donkey Trust, another project initiated by Stella. I clambered on the cart, my legs dangling over the side and, accompanied by Bubacar, took a track to a lookout point where the river spread out below.
Bubacar, known as Buba, had spent ten years working for Stella. The chef had been with her nearly 30 years. Buba was full of praise for his boss. Pointing to a watchtower in a rice field below, he explained that the Trust paid for night watchmen to guard the crops against hippos. "They use empty bottles, not guns. It's the noise that keeps the hippos away."
He stressed how the community is benefiting from the project and from the visitors. There are eight villages around the boundary of the park; the Trust directly employs around 40 people, but hundreds more benefit indirectly too.
Down in the nearby village, first stop was the Horse and Donkey Centre, where I was introduced to a gleaming black horse called Lazarus: "He's the founder, the boss." Back in 2000, Stella discovered Lazarus in an appalling state, sick, emaciated and covered in burns. She went to find a vet to put him out of his misery, leaving some food and drink for him. On returning, she found he'd started to eat and had the strength to stand, so she bought him from his owner. The Gambia Horse and Donkey Trust was born.
The Trust aims to reduce poverty by increasing productivity of horses and donkeys through welfare and management education. The Trust even provides donkeys to particularly needy people, keeping a regular check on them.
Next I visited the school and library, then the local clinic. All were funded by the Trust. The school was threatened with closure until the Trust got involved; now it has qualified teachers and is considered the best in the area. Headmaster Musa Darboe stated: "It is due to the interest of Stella that the school has reached this level."
Back at Badi Mayo food was being prepared for the afternoon feeding. At 4pm we headed out to Island 2, where camp manager Edirissa was throwing out watermelon slices, maize cobs and pumpkin. To my delight one of the first chimps we spotted was Frankie, up in a tree with Felix. She was thrown a bottle of liquid multivitamin drink, mixed with sugar to make it appealing.
Baboons were descending from the trees, snatching any food left lying on the ground. One male chimpanzee gathered up as much maize as he could hold in his arms and retreated up a tree, some falling out of his grip as he climbed. Mature female Stella, 27 years old and known as a gentle soul, let out a satisfied hiccup, followed by what sounded distinctly like a burp.
We headed upriver a short way, pulling up at the base of a hill. It didn't seem a long way up, but the view from the top over the river was stunning. As the sun went down we supped on some cold beers, overlooking a small, lush island, dubbed "Little Africa". In the water we could see a dozen hippos and a crocodile or two.
The next morning I woke up to the hoot of chimps on Island 1 and monkeys crashing in the trees around my tent. I'd grown to think of the baboons as the enemy, so it was a surprise to find that the camp had taken in a couple of rescue cases. I met eight-month-old Sarjo, an orphan with the face of a little old man. Each day he goes out in a boat with a park patrol - I saw him sitting in the launch, a serious expression on his face, as if he too was a park ranger. Word had spread that Badi Mayo had taken the baboons in and they were being offered yet more pitiful cases - a whole new dilemma to wrestle with.
I was leaving mid-morning so elected to have breakfast out on the boat so that I could squeeze in one last trip. Buba and I chugged around the islands, pointing out fresh chimpanzee nests to each other - the chimps make a new one every night.
We turned off the main river and up a palm-fringed creek into real African Queen territory. Every few metres there was another bird to exclaim over; an African darter, an osprey in a tree, the flash of a pygmy kingfisher. I lost count of how many palm nut vultures we saw, surely the most handsome vulture around.
As we headed back past Island 2 I was thrilled to see Frankie again, hanging around in exactly the same spot as the previous night, cute little Felix not far away. I wouldn't have wanted to leave without saying goodbye to her; somehow she had become a talisman for me, a symbol of what Stella was achieving here, both for the animals and the local people.
As I wrote this article, I received an email from David Marsden informing me that Stella had died. I remembered David's words to me: "Our aim is to build something that can live on without Stella or any one individual."
Stella has left an incredible legacy. Let’s hope that her work can indeed continue.
The author travelled wth The Gambia Experience
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