A primate location in the Congo jungle

Congo's forests are teeming with wildlife, but not tourists. Sue Watt checks into two new camps that put her within reach of birds, butterflies and wild gorillas

Monkeying around: rainforest in the Congo (will whitford)

Tiptoeing in the rainforest is never easy. Squelching underfoot and communicating only through hand signals, we tried to get closer to the shadows in the trees. Lango Forest is a popular haunt for monkeys, but these were something bigger, something special. Initially our guide, Karl, thought they were chimpanzees, rarely seen in the wild. But closer inspection proved him wrong.

"They're gorillas, wild gorillas," he whispered, wide-eyed and elated, "they've never been habituated, maybe never seen humans – unbelievable!" On seeing us, two giant apes rushed down the tree and disappeared into shrub. "That's what I love about Congo," he mused. "The forests are full of surprises, full of secrets... "

The rainforests of Odzala-Kokoua National Park, spreading 13,600sq km across north-west Congo, certainly have an air of the unknown about them. Established in 1935, Odzala is one of Africa's oldest national parks yet is rarely visited, the country being adversely affected by people's confusion with its volatile neighbour, Democratic Republic of Congo. With a unique biodiversity and Africa's densest population of Western lowland gorillas (some 20,000 of the world's 100,000 population live here), the area is ripe for discovery, which explains the opening of two camps by Wilderness, an upmarket tourism/conservation organisation.

The timing is fortuitous. African Parks, a South African organisation funded by a Dutch conservation foundation that regenerates depleted parks, assumed management of Odzala in 2010 on a 25-year mandate. With wildlife populations decimated through poaching, its first priority is to stabilise the core of the park, and for this it needs local people on side. Leon Lamprecht, AP's manager, explained: "The only way this park can have a long-term life is if communities benefit from it. Short-term benefits are the prevention of elephant poaching for ivory … tourism dollars will help communities: they'll see the long-term benefits outweighing the short-term."

Our two-hour flight from Congo's laid-back capital, Brazzaville, took us over seemingly endless expanses of rainforest. Beneath its canopy live some 430 bird species and 100 species of mammal, including 11 types of diurnal primates, more than any central African forest region.

Arriving at Lango Camp on a humid afternoon, it wasn't the beautifully rustic décor of the bar and lounge or the captivating view out over the river that struck me most: it was frogs, croaking and calling like a choir of thousands. The camp, inspired by the settlements of the B'Aka forest people, who lived here for 40,000 years, has stylishly simple tree houses built of raffia palms and wood, all perched on decking overlooking the river. After dinner, as we sat stargazing on our terrace, a tiny tree frog jumped on to my knee and we listened together to elephants trumpeting in the darkness.

The emphasis at Lango is on rainforest safari drives, walks and boat trips, and I soon realised that after years of travelling in southern and eastern Africa everything here is different. Elephants are shorter, with longer, straighter tusks. Forest buffalo look more like cows, red not black, and the impressive, bouffant-style horns have been replaced by short, stubby ones. Crocodiles are slender-snouted or dwarf, not Nile; monkeys putty-nosed or moustached not vervet; savannahs moist not parched. There are new animals to see including the stripy, deer-like sitatunga and the beautifully-named bongo, a huge, mainly nocturnal antelope.

In Lango Forest, like children on our first nature walk, we crouched down to look at weird new fruits such as wild mango and the sweet-smelling pineapple-shaped produce of the corossol tree. An exquisite wren-sized turquoise butterfly glided past, stealing the show. For the birders among us, the star was a rare black dwarf hornbill, preening himself on a branch.

After wading knee-deep through swamps and marshes we took a boat along the Lekoli River. Nearby, a lone bull elephant had also been wading through swamps, with watermarks almost to the top of his haunches. Drifting along the now calm waters, we received a running commentary of monkey mania from Karl and Fraser, steering our aluminium vessel. "There goes a De Brazza's monkey," said Fraser, then Karl urged "check out those guereza colobus moving like ninjas". My favourites were the playful putty-nosed monkeys chasing each other in circles, so called because their white noses look like squashed blobs of putty stuck on black faces. Bird lovers were in raptures: within five minutes a goliath heron emerged to our right and a giant kingfisher to our left, but both were outshone by the famously elusive Pel's fishing owl that suddenly darted across the river.

"That's a birder's equivalent to seeing an aardvark!" Karl said, explaining the excitement. "Unbelievable!"

Still scarred from decades of poaching, wildlife here is skittish. But it will relax once it learns that the park's new guests are no threat. Gorillas, however, are more used to humans with three groups having been habituated by the renowned primatologist Dr Magda Bermejo and her husband German Illera.

A bumpy two-hour drive away, Ngaga Camp, similar in design to Lango, is Wilderness's gorilla-tracking base in the heart of the Ndzehi Forest. "Welcome to the Gabon highway," Karl announced en route as our Land Cruiser squeezed between the overgrown reeds and grasses that concealed what was little more than a severely pot-holed dirt track.

Even the gorillas are different here. Smaller than their mountain cousins and classed as critically endangered, the population is decreasing through disease, the bush-meat trade and loss of habitat. Visitors follow a strict viewing protocol to alleviate stress and the risk of contamination with human diseases. This includes restricting visitor numbers to four per group, keeping a minimum seven-metre distance from the gorillas, wearing masks when watching them and spending just one hour in their company.

We set off in mid-morning humidity to meet the Neptuno group, named after their mighty silverback. Our expert tracker, Zepherin, followed a grid of pathways cut through dense Marantaceae shrub, akin to gigantic aspidistras about two metres high. This is staple ape food, explaining why around 105 gorillas have made this particular area their home. Disturbed vegetation, half-eaten wild ginger stems and an upside-down ants' nest that gorillas had snacked on all proved that we were on the right track. Eventually, we turned off the main path down one of the "tunnels" in the Marantaceae created by the gorillas. Then, we suddenly saw Neptuno sitting in a tree munching leaves. Around him were the rest of his family, 18 in all, warming themselves in the sun.

Pan, a cocky two-year-old, lay on his back, sometimes scratching his tummy or brow, keeping an eye on us while Caco, aged six, climbed half-way up the trunk and just stayed there seemingly posing for photos. Ceres sat right at the top of the tree grooming her little baby, its spiky hair silhouetted against the sun. Mesmerised by this happy family scene, our hour flew by. But just before we left, as if he was timing us, Neptuno performed his star turn, descending the liana vine like a brawny ballerina, elegantly sliding his 200kgs of muscle down to the ground.

"Neptuno is special," Magda confided that evening. "The guides, the trackers, they all feel the same …" The next day, we tracked Jupiter's group of 25 gorillas for four hours, following footprints and discarded fruits, broken Marantaceae and fresh-smelling faeces on the trail. But it seemed they were constantly and rapidly moving on. Eventually Karl briefly spotted one gorilla in a tree about 100 metres away but the group was hidden in such dense vegetation it was impossible to penetrate.

Returning disappointed, we learnt that a solitary wild male had been threatening Jupiter, forcing him to rush on without even stopping to eat. With the gorillas' wellbeing always paramount, Magda decided that Jupiter had suffered enough stress for one day and that we shouldn't return for another attempt to see him. And with the itinerary only allowing for two tracking experiences in two days at Ngaga, with no contingency for non-sightings, Jupiter would, for us at least, remain unseen.

It was a different story for the group who tracked Neptuno that morning. One guest showed me her photos, her face still glowing with amazement. There was Neptuno, big and burly on all fours in a clearing, feeding contentedly. Nearby, youngsters were happily fooling around and mothers were nurturing their babies. "No one spoke when they got back, not even the guide. They were just stunned," Charlotte the camp manager told me. "It's the best sighting we've ever had." As Karl had said after our first, unexpected gorilla encounter in Lango Forest: unbelievable…

Getting there

Sue Watt travelled with African specialists Zambezi Safari & Travel Company (01548 830059 zambezi.com). A seven-night itinerary with Air France flights (airfrance.co.uk) via Paris to Brazzaville – one night at Mikhael's Hotel, Brazzaville (mikhaelshotel.com) and three nights each in both Lango and Ngaga Camps – is priced from £5,557pp. This includes all flight and vehicle transfers, full board, most drinks and all activities.

Visiting there

The minimum age for gorilla viewing is 15. Guests with colds, flu or other respiratory-tract symptoms will not be allowed to track gorillas to minimise the risk of infecting them.

More information

British passport-holders require a visa to visit Congo, which must be obtained before departure. A single-entry visa costing £60 is available from The Honorary Consulate of the Congo, 3rd Floor Holborn Gate, 26 Southampton Buildings, London WC2A 1PN (020 3077 9958; bit.ly/EmbCongo).

All visitors to Congo must have a Yellow Fever Vaccination Certificate.

Odzala Wilderness Camps: odzala-kokoua.com