The present study describes Ecology of Houbara Bustard (Chlamydotis undulata macqueenii), a desert adapted species in Pakistan. In Punjab the total wintering habitat of Houbara Bustard is 32,300 km2, and Rajanpur/Rojhan shares 4,600 km2 (14.24%), Thal 4,800 km2 (14.86%) and Cholistan 22,900 km2 (70.90%). Nag Valley (Kharan, Balochistan) comprises about 1500 km2 breeding habitat of Houbara.
Vegetation cover varied from place to place depending upon the texture and structure of the soil and was greatly influenced by rainfall. In Rajanpur/Rojhan 33 plant species, belonging to 20 families were recorded. Importance value for plant species in Rajanpur/Rojhan was worked out for the years 1999, 2000 and 2001. Based on the importance value the dominant species were, Dipterygium glaucum, Calligonum polygonoides, Prosopis cineraria, .cymbopogon jwarancusa, Lasiurus scindicus, Capparis decidua, Leptadcnia pyrotechnica, Haloxylon salicornicum and Fagonia indica. However feeding propensity of Houbara in descending order was Dipterygium glaucum, Capparis decidua, Fagonia indica, Haloxylon salicornicum, Farsetia hamiltonii, and Tribulus longipetalus
In Thal, 36 plant species, belonging to 18 families, were recorded. Dominant species on the basis of importance value were, Calligonum polygonoides, Aerva javanica, Cymbopogon jwarancusa, Dipterygium glaucum, Lasiurus scindicus, Leptadenia pyrotechnica, Haloxylon salicomicum, and Fagonia indica. In Thal area, dominant food plants of Houbara Bustard were, Dipterygium glaucum, Haloxylon salicomicum, Fagonia indica, Farsetia hamiltonii and Capparis decidua.
In Cholistan 102 plant species, belonging to 37 families, were recorded. Data on importance value, based on three years (1999-2001) revealed that dominant species were, Aerva javanica, Dipterygium glaucum, Cymbopogon jwarancusa, Lasiurus scindicus, Calligonum polygonoides, Suaeda fruticosa, Haloxylon salicornicum, Fagonia indica, Ochthochloa compressa, Haloxylon recurvum, Crotalaria burhia, Cynodon dactylon, Capparis decidua, and Farsetia hamiltonii. The dominant food plants of Houbara Bustard were, Dipterygium glaucum, Suaeda fruticosa, Haloxylon salicornicum, Fagonia indica. Capparis decidua, Farsetia hamiltonii, Tribulus longipetalus, Indigofera argentea and Salsola baryosma.
Present studies also revealed that Houbara generally avoided the high sand dunes (above 6 meter) and preferred interdunal flats and small sand dunes (2-6 meter). Consequently more Houbara tracks (38.43%) were recorded on saline clay patches, having Capparis decidua, Suaeda fruticosa, Haloxylon recurvum and Salsola baryosma plant species. In interdunal flates, 33.79% Houbara tracks were observed. Some sandy habitat with Calligonum polygonoides, Lasiurus scindicus species had only 2.78% tracks, but those sandy. habitat, dominated with Dipterygium glaucum, Haloxylon salicornicum, Farsetia hamiltonii and Indigofera argentea species had more Houbara tracks (25%). The areas with more than 50% shrub covers were also avoided, because in such areas due to thick cover visibility of the bird relatively becomes poor.
In breeding habitat of Nag Valley, 118 species belonging to 61 families, were recorded. The most dominant species on the basis of importance value were Zygophyllum eurypterum and Rhazya stricta, which grows in graval sand, sandy clay and sandy streambeds. Pennisetum divisum and Convolvulus spinosus were also wide spread species found in sandy clay and sandy streambeds. The other common species of Nag were Otostegia aucheri, Astrogalus stocksii, Cymbopogon jwarancusa, Haloxylon ammodenderon, Haloxylon griffithi, Fagonia indica and Peganum harmala. Two new species Douepia tortuosa and Cynomorium songaricum were also recorded from Nag area.
Present studies about its population in the Punjab during 1999, 2000 and 2001, reveled that population of Houbara was 4,854, 4,729 and 4,746 birds respectively. There was 2.57% decline in 2000 but no change in population was recorded in 2001. Overall densities in Punjab were calculated as 0.152±008, 0.150±007 and 0.147±006 birds/km2 in 1999, 2000 and 2001 respectively. This reflects minor fluctuations in population dynamics.
In Nag Valley (Kharan, Balochistan) the density was 0.141±024 birds/km2 in 1999, which gradually decreased to 0.116±023 in 2000 and 0.103±023 birds/km2 in 2001.
The results of gizzard analysis revealed that Houbara fed heavily on desert plants in their wintering areas in the Punjab. Parts of plants like seeds, leaves, flowers and young shoots of 19 plant species belonging to 13 families were consumed, indicating a wide range of Houbara food. The preferred food plant was Dipterygium glaucum, constituting 39.34% of total plant matter. The other plants were Capparis decidua (26.17%), Farsetia hamiltonii (10.52%), Fagonia indica. (5.77%), Cicer arietinum (2.3%), Haloxylon salicornicum (1.63%), Salsola baryosma (1.59%) and Tribulus longipetalus (0.86%).
The preferred animal food of Houbara bustard was beetles. The leading family was Tenebrionidae with 7 species. The most favorite species of Houbara was Adesmia aenescens 49.30% of total animal matter. The other dominant species were Arthrodosis sp 11.36%, Pimelia inexpectata 10.72% and Pimelia indica, 9.90%. These four species collectively made up of 81.29% of total animal food indicating that Houbara is also very selective in animal food. The less favorite species were Formica rufa (2.39%) and Blaps mucronota (2.24%) while other were used occasionally.
Houbara Bustard fed chiefly on plants in wintering grounds but with the increase in cold, consumption of animal food significantly increased. Perhaps the bird required more energy in cold weather. The consumption of animal food was low in October/November, moderate in December and high in January/February. The consumption of animal food further increased in March, due to breeding and migration activities.
Samples of Houbara dropping collected from birds kept in captivity at Houbara Research and Rehabilitation Center (HRRC) Rahim Yar Khan were studied under microscope. The eggs of different parasitic species were observed in different groups of Houbara. Sixty percent of the birds freshly arrived in the center in 1999 were infested with parasites: Fascioloides, Ascaridia, Capillaria, Aacaris and Avitellina species. Birds which were already in captivity (1997), showed 53.33% infestation of parasites: Fascioloides, Capillaria, Raillietina and Aacaris species. Similarly 40% healthy, 55% ophthalmic, 46.66% weak and 60% birds arrived from Karachi were found infested with eggs of parasites in their dropping. Eighty percent birds recovered from different diseases at HRRC were also found harbouring endoparasites. Only 6 birds (13.63%) out of 44 collected from the wild were infested with eggs of endoparasites.
Morphometric analysis of 235 Houbara (Male 136, Females 99) were carried out. Comparison of sexes suggested that there were non-significant differences (P>.05) between males and females for toe + claw and beak length from nostril. Other characters differed significantly in both sexes. Body weight was the most variable character in both males and females, followed by wing and tail. Beak width and beak length were the least variable characters in both males, females.
Houbara with transmitters were released in different areas and monitored up to expiry of batteries to study the survival ratio. The release sites were Houbara Research Rehabilitation and Breeding Center (HRRBC) at Nag Valley 27° 16 N, 64°50 E, Kadinwali, Khairpur 27° 09 N, 69° 19 E and Houbara Research and Rehabilitation Center (HRRC), Salluwali Rahim Yar Khan 28° 32 N, 70° 55 E. The survival ratio in Nag was 60%, in Khairpur 46.47% and in Rahim Yar Khan 80%.
Arabs Falconry, trapping, overgrazing, fuel wood collection and habitat shrinkage were main threats for Houbara population. Effective management involving local commul1ities is required for the sustainable use of Houbara and other wildlife.