It's a scintillating morning in north Botswana, and I'm privileged to be standing within touching distance of an African savannah elephant that seems as big as a Hong Kong minibus. There's just a shrub between us as she curls her trunk around a cluster of leaves, rips them off and pulls them into her mouth.
This female isn't wild but part of a small, loosely captive herd. Walking with her are another female and a two-year-old calf. Two men are riding and guiding the big females, another walks as a guard, clutching a rifle - for use in the unlikely event of a wild animal attack - while two tourists and I stroll along, temporary members of the herd.
All the members of this group have been given names, and Cathy is the closest I'll ever come to meeting Nellie the Elephant. In the children's song, Nellie left the circus "and trundled back to the jungle". ("Off she went with a trumpety trump. Trump, trump, trump.") After being captured in Uganda at the age of two, Cathy lived in a Canadian safari park until being shipped back to Africa, eventually joining this pioneering project, overseen by the charity Elephants for Africa, which aims to show that the animals can be trained to participate in safaris like this. The animals are kept in an enclosure at night but during the day, when they are not involved in safaris, they are free to roam and even return to the wild if they so desire, which some have done.
We move on through the bush. At times I stop and take photos, trying to be mindful of advice not to turn my back on the baby lest she decide to "play" with me: weighing more than 600kg, she could easily knock me down.
I've come to Africa after having become involved in efforts in Hong Kong to stem the ivory trade, which has led to unsustainable levels of poaching. Last year, perhaps as many as 30,000 elephants were killed in Africa, for ivory that was mostly destined for China. Hong Kong customs seized tusks from at least 1,675 elephants last year. Partly, I want to learn if it's possible to help the cause by becoming an ecotourist.
As part of an itinerary planned by Hong Kong-based Asia to Africa Safaris, I'm visiting two safari lodges - Abu Camp, Cathy's home in the heart of the Okavango, a 150,000-square-kilometre delta within a desert, and King's Pool, by the Linyanti River, on the border of northeast Botswana and Namibia. While Abu Camp has made a name for itself by offering elephant-back safaris (a rarity in Africa, unlike in Asia), both lodges offer game drives and boat trips in search of wild elephants and the multitude of species that share their habitat.
Not that you have to go far to see the wildlife. Hippos are immersed in pools in front of both lodges, an African fish eagle proclaims territory beside Abu Camp and, at King's Pool, the buffet attracts uninvited guests, including a baboon that chases a waiter into the kitchen and a warthog that busily digs a hole beneath my bungalow.
Thanks to drivers who double as guides with sharp eyes and encyclopaedic knowledge of the fauna and flora, outings prove astonishingly revealing. We soon find giraffes, with horse-size babies that cling to their two-storey-high mothers, and several species of antelope, the most common being impalas, many of which have just given birth to doe-eyed youngsters ahead of the rainy season. All around, small herds of zebra graze.
Predators are far scarcer. We pause at a hyena den, where a battle-hardened female nurses her cubs. A call over the walkie-talkie alerts us to the presence of a female leopard, which is relaxing on the ground. On a shaded log above her, a cub almost dozes on the remains of a young impala, looking as content as a house cat sated on cream.
There's a wonderful variety of birds here, too. Lilac-breasted rollers are extravagantly colourful crow relatives that perch on branches and swoop after insects. Gathered at small pools are water birds ranging in size from plovers to 1.5-metre-tall storks with pied plumage and giant red and black bills. Turkey-sized hornbills shuffle along the ground, seeking out insects and small reptiles.
I alight from the vehicle to creep close to a colony of carmine bee-eaters - intense red and blue birds that are returning with bees and dragonflies with which to feed youngsters hidden in underground burrows. I keep an eye out for the black mamba seen in the area by other lodge guests the day before, but there's no sign of the venomous snake.
Nor does a buffalo appear and charge me, nor a pack of lions emerge to eye me for lunch. There are dangers here, for sure, yet nothing as absurd as television shows such as Man vs Wild might suggest. Indeed, the only lion I see strolls casually past us as we watch from the vehicle, and almost falls asleep close by.
The wealth of plants and animals here depends partly on the elephant, a "keystone species". Elephants not only munch leaves they also knock down trees to ensure there's open grassland, while their dung provides food for termites and other creatures. Without elephants, the landscape and wildlife would be transformed. And this would in turn affect tourism, the second-highest revenue earner for Botswana, after diamonds.
"The tourism industry has changed my life; it's made me who I am right now," guide Ndebo Tongwane says. Born in a farming area, he now supports his extended family through guiding.
Of course, there can be significant downsides to tourism, not least of which are the safari ventures wherein too many vehicles chase after the animals, their tracks damaging fragile landscapes and their presence making it hard for predators to hunt and feed properly. The development of tourist accommodation potentially leads to pollution that will harm the sensitive Okavango. Nevertheless, tourism seems vital for wildlife conservation here, as it can also help counter threats such as the expansion of cattle farms, which leads to overgrazing, disturbance of wildlife and the killing of elephants, lions and other predators by protective farmers.
Thanks to low-impact - and high-priced - tourism, the lodge environs I visit remain close to pristine, and with government support and military patrols, elephant poaching is not rampant in the region. The wild elephants we encounter during game drives remain relatively relaxed as people approach.
One morning, a guide and I come across a herd of about 30 elephants moving in a scattered formation, grazing on low trees. We drive to the front of the herd and stop, to watch them pass. For a few minutes, we're in the midst of the herd. Females with calves stroll casually past. An adolescent male pauses to stare at the vehicle, shakes his head and trots on by. The only sounds are of elephant trunks ripping up foliage to eat; they tread so carefully on sensitive feet that we hear no twigs or branches snapping.
Four elephants file through a gap between trees, making up the rear of the herd. Then, they are gone, hidden by the sparse cover, as if they had melted into the bush.
Getting there: South African Airways (www.flysaa.com) flies daily from Hong Kong to Johannesburg, and from the South African city to Maun, a town in Botswana that is a hub for light aircraft trips into the Okavango. Asia to Africa Safaris (www.atoasafaris.com), which provided this writer's visit free of charge, tailor makes trips to Botswana and elsewhere in the continent.