North African species
The houbara bustard is a medium sized bird with a wingspan of up to 1.5 meter. The bird is white bellied, with upperparts pale sandy buff, mottled and lined with darker brown.
In flight, the long wings show large areas of black and brown on the flight feathers. Males are slightly larger than females (at mean, 2.2 against 1.2 kg), with longer erectile filamentous neck plumes involved in the display.
The houbara bustard is a shy and cryptic bird. It is reluctant to fly and can walk kilometres while foraging. It feeds all the day but mostly in the thin light of dawn and dusk.
In the Canary Islands it lives there year-round, while in North Africa the houbara is known as a partial and deferential migrant: adult males are sedentary with well delimited home-ranges (at mean 17 km²), while most of adult females exhibit seasonal movements between separated breeding and wintering areas (total home range > 140 km²).
Female movements of up to 800 km have been recorded in Morocco (ECWP, unpublished data).
The houbara is a polygynous bird with an exploded-lek mating strategy. Males aggregate at dispersed leks that females visit solely for mating and fertilizing their eggs. The only contribution of males is their semen and females lay and brood alone without any male parental care.
At leks, males display on traditional display sites usually established at three years of age. They exhibit an elaborate courtship dance to compete with neighbours for the affection of females. Among the bustards, a family known for ostentatious displays, the houbara boasts one of the most flamboyant. The male puffs out his ornate feathers on his crest, chest and neck while making long, slow and graceful steps. White filamentous feathers are erected forward, while black feathers are erected back up of the neck and fan-shaped. After few seconds, the male throws its head back between its shoulders and promptly start a frenetic course, making strait lines and / or circles. At this stage, white ornate feathers of the chest, neck and crest are contiguous and make it resembling a white balloon. With no potential mate in its vicinity, it then stops its course brutally, keeps standing with all display feathers erected and throwing its head upward 2 to 8 times, whilst emitting a deep low frequency call named “booming”. It then rests few seconds and begins a new courtship sequence. The courtship display happens from January to May every year. Usually, it begins in the afternoon and ends in the morning, avoiding the hottest hours of the day. During daytime, males perform complete cycles of mating displays (runs and static “booms”), with peak activity at sunset and sunrise. At night, the display continues as stationary, with birds merely booming.
Face to a mate, the male enters a pre-copulation display: stretching is neck forward with white filamentous feathers erected, walking toward the female by twisting its body from left to right and clapping its beak at each oscillation.
Most of females reach sexual maturity at two or three years old. Generally, they lay from March to June, with a peak at the end of April. The laying periods vary according to latitude and between years depending on environmental conditions, especially rainfall occurrence.
In North Africa, houbara lays one to four eggs. Houbara eggs are pale grey-olive, mottled generously with brown spots. The incubation period is 23 days. The female and her brood leave the nest a few hours after hatching. Chicks are fed beak-to-beak by their mother. Houbara chicks are able to fly at 30 days old, but remain with their mother until two to three months old.
The houbara is well adapted to desert environments and its range reflects these adaptive advantages. In North Africa, it prefers little-inhabited steppes and semi deserts with rainfalls ranging from 50 to 250 mm per year, which provide open lands and shrubby vegetation.
During the year, both sexes are selective in their use of available habitat types. In the non-breeding season, habitat use does not differ between sexes, and houbaras forage in mix flocks of males, females and juveniles. They use preferentially well vegetated patches, especially those that were temporarily flooded after rainfalls and water courses (wadis). During the breeding season (end of winter to the beginning of summer) habitat use differ between sexes. Males forage in water courses and display on open reg (gravel plain) characterized with small vegetation cover (3%) and height (<5 cm), looking for conspicuousness.
Females lay their eggs on the ground often close to a bush that provides shelter from both sun and predators. Nesting females used a heterogeneous complex of habitats provided by a network of wadis, crossing regs covered by tall perennial plants (> 10 cm), which offer both food and cover for their brood.
So well adapted to semi-desert environment is the houbara that it does not even need to drink water. Rather it receives all the moisture it needs directly from food. It is an omnivorous bird, feeding on plants, invertebrates and small vertebrates as lizards.
In fall and winter plants represent 60% of the diet with houbara consuming mainly green parts of Asteraceae, Poaceae and Chenopodiaceae. In spring and summer the plants represent less than 35% of the diet as birds shift towards an animal diet mainly composed of Ants and Beetles.
Status and threats
Among the houbara’s most pressing threat is the over hunting and loss of suitable habitats due to various human activities. In addition, land reclamation for recreational, tourism (Canary Islands), industrial or agricultural purpose take a toll.
Among the sadder truths about the houbara’s decline is the persistence of illegal hunting and poaching. Despite its endangered status and international bans on trade in houbara, unauthorized hunting continues to contribute to the species’s decline. Each year, the illegal trade in poached houbara destroys thousands upon thousands of wild houbaras.
Consequently, the houbara numbers have been in steep decline for decades and, in 2004, the World Conservation Union (IUCN) placed the houbara on its “Red List” of endangered species, listing it as “Vulnerable”.
Today, reliable data on houbara densities and their variations throughout the species range are still lacking, impeding adequate conservation planning. Recent protection measures in the Canary Island and in Morocco (ECWP conservation strategy) allowed significant increase in the population size. However, similar conservation measures are needed at the scale of the entire species range.