Born To Be Tame

Natural History, June, 2001 by Yolanda van Heezik, Philip Seddon

To survive in the desert of Saudi Arabia, captive-bred bustards have to learn to go wild.

Imagine you're living on your own for the first time. Away from the comforts of home and in a strange town, you're preoccupied with looking for a place to get a meal and you inadvertently wander onto a dark street. A large man comes toward you. Perhaps he could give you directions. You smile hesitantly. He smiles back and then flourishes a knife. Too late, you realize you've made a fatal mistake.

In the natural world, naivete is costly, but it is also rare in animals that share their environment with natural enemies. Constantly faced with the danger of becoming someone else's dinner, prey animals are skilled in recognizing and avoiding potential predators. In some species this ability is largely innate, while in others it seems to be learned from parents or other members of a herd or flock. Animals raised in an artificial environment and without such guidance often lack the predator-detection skills of their wild cousins.

For nine years we worked at a captive breeding center for Asiatic houbara bustards in Saudi Arabia. At the National Wildlife Research Center in Taif, female bustards are artificially inseminated and the chicks are hand-raised and then released. The goal is to reestablish healthy populations of bustards in their Saudi Arabian range. One of the first challenges the program faced was how to prepare naive bustards to survive--to eat and not be eaten--in the desert.

Camouflaged and, in their natural state, wary birds, Asiatic houbara bustards are at home in the undulating steppes and semideserts of the Arabian Peninsula, western and central Asia, and the Indian subcontinent. Superbly adapted to arid environments, wild houbaras do not need to drink water but manage to get all the moisture they need from their food. Indeed, part of the secret of the bustards' survival may be their varied diet. Opportunists at heart, they will try most edible objects they encounter, from juicy berries and young green shoots to crunchy beetles and sunbathing lizards. Though powerful fliers, houbaras prefer to walk and are more difficult to discern when on the ground. When they do take to the air, their size (wingspread is about five feet), their deep wingbeats, and the black patches on their wings and neck make them easy to recognize. Houbaras' strong flight, coupled with a fighting spirit, make them a premier quarry in the ancient sport of falconry. This kind of hunting, in which the falcons are trained to attack much larger birds, is one reason bustards are threatened throughout much of their range.

Houbara bustards are also sensitive to human disturbance. Before Saudi Arabia's oil-fired economic expansion, the wanderings of nomadic herdsmen were dictated by the presence of water and green vegetation. Today water is trucked to livestock, and both the herds and the four-wheel-drive vehicles penetrate once pristine landscapes. In response to the decline of resident houbaras in the Arabian Peninsula, the Saudi government began a conservation program in 1986. This project included captive breeding and the creation of large protected areas. By 1992 the successful program of artificial insemination and incubation had produced a surplus of chicks, enough to begin introducing some of them into the wild. Juvenile birds, from thirty-five to forty-five days old, were at first released into a predator-free enclosure of about one and a half square miles, where they could learn how to find natural food. In their own good time, the young birds could simply fly out into the wider reserve, a fenced area of 850 square miles that was free of livestock and human predators but had a full complement of natural predators. Some bustards, on first leaving the enclosure, immediately retreated back inside, while others headed off into the desert.

Considering the enormous transition the young birds had to make, many of them fared well as far as food finding was concerned. After growing up on a diet of unlimited food pellets, alfalfa, mealworms, crickets, and water, they were somehow able to recognize and collect their natural plant and insect foods. They coped without water in temperatures that soared above 100oF and eventually even figured out how to breed successfully.

The main stumbling block along the road to self-sufficiency was predation. As more and more of the newly free young birds fell victim to deadly attacks, we considered a list of likely suspects. The delicate little Ruppell's fox inhabits the region, but its predominantly insectivorous diet and small size argued against its being the villain. (However, should a hungry Ruppell's fox blunder upon a recently released bustard barely able to fly and searching for its water dish, then the fox is likely to prefer the bird over another beetle.) The lovely, wide-faced sand cat could have preyed on some birds, but the habits of this desert species are little known. Later on, we found that eagle owls could become habitual houbara killers once they discovered how easy it was to dispatch naive birds. But our investigation of the tracks and other signs around predator-killed carcasses indicated that the main culprit was the red fox.