Blackwell Publishing Ltdmigration and Range Use of Asian Houbara Bustard Chlamydotis Macqueenii Breeding in the Gobi Desert, China, Revealed by Satellite Tracking

Home , Haloxylon ammodendron, Muyunkum Desert

Ibis (2006), 148, 343–351

Blackwell Publishing LtdMigration and range use of Asian Houbara Bustard Chlamydotis macqueenii breeding in the Gobi Desert, China, revealed by satellite tracking

JACKY JUDAS,1* OLIVIER COMBREAU,1 MARK LAWRENCE,1 MOHAMMED SALEH,1 FREDERIC LAUNAY1 & GAO XINGYI2 1National Avian Research Center (NARC), Environment Agency, PO Box 45553 Abu Dhabi, United Arab Emirates 2Xinjiang Institute of Ecology & Geography, CAS, no. 40 South Beijing Road, 830011, Urumqi, People’s Republic of China

Four adult male Asian Houbara Bustards Chlamydotis macqueenii were caught on their breeding grounds in the Gobi Desert of China and tracked by satellite from July 2000 for from 5 months to > 3.5 years. Wintering areas were identiﬁed for two individuals, one on the Turkmenistan/Uzbekistan border in the Amur-Darya valley, the second at the Iran/ Turkmenistan border. One individual used the same wintering and breeding areas for three consecutive years. Overall departure dates from breeding grounds ranged from 29 September to 14 October, with arrival on wintering quarters from 23 October to 7 November. Birds left their wintering grounds between 2 and 21 March and reached their breeding areas between 11 and 21 April. The mean overall migration distance was 3935 km (sd = ± 229, n = 9). Houbara Bustards mainly followed steppe areas to migrate avoiding the highest elevations of the Himalayan massif and travelling 267 km/day on average. Pre-breeding migration lasted longer than post-breeding and included more and longer stopovers. The Taukum Desert and Jungar Basin are critical areas for migration of eastern Houbara populations. Breeding range, used for 5.5 months, was 274 km2 (sd = ± 53, n = 4), whereas wintering range, used for around 4 months a year, was 76 km2 (sd = ± 22, n = 3). Range use pattern appeared similar for Asian Houbara released in central Saudi Arabia, but differed from the African Houbara Bustard. More investigations are required to determine the effects of food availability and meteorological conditions on the migration pattern and on the use of stopovers by Asian Houbara Bustards.

The Asian Houbara Bustard Chlamydotis macqueenii Bustards (hereafter Houbara) while maintaining is a ground-dwelling migrant inhabiting steppe areas falconry. Identification of the breeding areas for from the Middle-East (Syria, Saudi Arabia) to China Houbara wintering in Arabia was identified as a pri- and Mongolia (Collar 1980, 1996, Cramp & Simmons ority (Seddon et al. 1995). Previous satellite-tracking 1980). For centuries, it has been the main quarry of studies revealed migration routes of Houbara and Arabian falconers (Upton 1989). In the last few de- the complex connectivity between breeding and cades, over-hunting and over-grazing have eliminated wintering areas (Osborne et al. 1997, Combreau et al. most resident populations on the Arabian Peninsula, 1999, 2001, Launay et al. 1999, Tourenq et al. 2005). and more eastern wintering migrant populations have Thus, some Houbara captured in winter in the United been declining (Collar 1980, Goriup 1997). Concern Arab Emirates migrated to China and Mongolia to over this population decrease has led the United Arab breed. This paper describes the migration routes, main Emirates and Saudi Arabia to develop conservation stop-over locations and wintering areas of Houbara programmes with the main goal of securing viable breeding in the southern edge of the Gobi Desert in resident and migrating populations of Houbara China and provides the first results on one Houbara monitored for more than two consecutive seasons, *Corresponding author. and information on its site fidelity to breeding and Email: [email protected] wintering areas.

344 J. Judas et al.

METHODS Selection of locations Of the seven location classes of accuracy provided by Capture area ARGOS, we used only the three upper quality ones Capture of breeding Houbara was conducted in (ARGOS classes LC 1, 2 and 3; Argos 1996, Britten the southeastern part of the Gobi Desert, over the et al. 1999, Hays et al. 2001). We calculated inter-fix Alashan Plateau, which lies between 1000 and geodesic distances with the Animal Movement exten- 1500 m a.s.l. (People’s Republic of China, Gansu sion (Hooge et al. 1999) in Arcview 3.2 (ESRI 1996) Province, 39°N, 102°E). In this region, winter in the WGS84 coordinate system. The travel rate (in temperatures can fall to −35 °C, whereas summer km/day) was assessed between successive locations temperatures can reach 40 °C. Annual rainfall rarely with a minimum 1-day time interval. Speed between exceeds 150 mm and mainly occurs in summer but successive locations was also assessed by dividing the with important temporal and spatial variations inter-fix distances (in km) by the corresponding time (Times Books 1998). Shifting dunes alternate with intervals (in h). Locations that produced excessive arid stretches occupied by xerophytic salt-tolerant unrealistic speeds were excluded from samples. This shrubs (Haloxylon ammodendron and Reaumuria case mainly occurred when the time interval between soongolica). Semi-desert shrub communities (Artem- successive locations was less than 30 min. Although isia salsoloides, A. ordosica, Zygophyllum xanthoxy- no information is available on Houbara flight speed, lum and Calligonum mongolicum) are found in less by referring to other species of similar size (Berthold arid areas, and numerous oases, fed by mountain 1993, Lincoln et al. 1998), we considered a speed snowmelt, occur along the northern flank of the as unrealistic when exceeding 80 km/h. Following Qilian Range in the south. Few nomadic herders Shimazaki et al. (2004), we assigned to each location graze livestock on the Chinese Alashan Plateau, an an approach travel rate (Ta) and a departure travel area of very low population density. However, rate (Td), calculated from immediately precedent measures taken by the Chinese Government have and subsequent locations, respectively. Comparing encouraged the transfer of the human population both Ta and Td to a travel rate threshold (Tt), four to increase agricultural productivity and industri- states of movement were defined: alization; empty deserts are progressively being • ‘Stay’ for Ta and Td = Tt converted into inhabited or irrigated agricultural • ‘Departure’ for Ta = Tt and Td > Tt lands. • ‘Travel’ for Ta and Td > Tt • ‘Arrival’ for Ta > Tt and Td = Tt The travel rate threshold was determined by K- Capture and tagging means clustering (Wilkinson et al. 2004) as the Four adult male Houbara were caught on 13–15 maximum travel rate value of the first cluster, which May 2000 on their display grounds. Nylon lines with grouped locations with lower travel rates. snares were fixed on the ground around a stuffed We used locations with lower LC accuracy (LC 0 female Houbara used as decoy. The four males were and A) to refine travel dates and migration routes when fitted with 35-g solar-powered satellite transmitters no other locations were available for a given day (Microwave Telemetry Inc., Columbia, MD, USA) during the migration periods. Migration routes were harnessed on a Teflon ribbon backpack (for details overlapped in Arcview to a Landsat satellite view of see Osborne et al. 1997). The platform terminal the world (Worldsat International 1997) with 1 pixel/ transmitters (PTT), operated through the ARGOS km2 accuracy to determine routes according to system in Toulouse (France), were programmed to geographical features. Location names followed the work on a 10-h on/21-h off duty cycle. All Houbara Times Atlas of the World ( Times Books 1998). Stop- were ringed, weighed and measured before release. overs were determined using all previously defined Indices of PTT orientation measured by a built-in arrival and departure events occurring between breed- position sensor provide the ability to check a bird’s ing and wintering grounds. Distances were calculated activity through variations of this index from one as the sum of successive travel segments between record to another. We considered a bird as dead selected locations. Home-range sizes were computed when these indices ceased to vary substantially and using the Kernel method (Worton 1989), including the date of death as the first day on which the index 90% LC 1–3 locations on breeding and wintering stabilized. quarters. Exploratory analyses were performed to

Migration and range use of Asian Houbara Bustard 345

determine the smoothing parameters using the least- Migration routes square cross-validation (LSCV) method (Seaman & Powell 1996) for all wintering and breeding periods The four monitored Houbara moved west-northwest recorded for the four Houbara (n = 12). The mean of from their breeding grounds up to the easternmost all resulting LSCV smoothing parameters was then edges of the Tien Shan Mountains along an approxi- used to re-run home-range computation. mately 600-km-long path (Figs 1 and 2). They followed this mountain range west up to the deserts bordering Lake Balkash in eastern Kazakhstan. From Statistics there, their routes curved southwest, turning around To avoid data pseudoreplication, we averaged the the edges of the high Tien Shan, Pamir and Hindu number and duration of stopovers to only one value Kush mountains through southeast Kazakhstan and per individual, but we considered pre- and post- Uzbekistan to end their journeys on their wintering breeding migration as independent events. Home- grounds in the Amu Darya valley, or on the border range sizes were also averaged to a single value per of the Karakum desert in southeast Turkmenistan individual per season (breeding and wintering). Given near the Iran border. The locations recorded around the small sample size, comparisons of means were the Tien Shan Mountains revealed that the birds performed using Mann–Whitney non-parametric U- crossed this area through different natural passes. tests. All statistical values are expressed as mean ± sd. During the 2000 post-breeding migration, three birds ﬂew south of the Tien Shan Mountains towards the Takla-Makan Desert (Fig. 1). Bird 20664 then RESULTS crossed into the Jungar Basin through the Turfan Pass (southeast of Urumqi), whereas birds 20672 and Monitoring period 28132 continued westward. However, the lack of Houbara movements were monitored by satellite for locations for several days did not allow us to identify periods ranging from 5 months to more than 3.5 years where these two last individuals crossed the Tien depending on individuals (Table 1). The signal trans- Shan Mountains. The fourth bird (28133) travelled mission of bird 20672 suddenly stopped on its arrival north along these mountains to cross the Kazakhstan/ in Kazakhstan on 12 October 2000. The signal of bird China border via the Emel valley. Over the next 3 years, 20664 was lost on 30 November 2000 and retrieved bird 28132 joined the Jungar Basin through a natural 3 months later, 295 km away, but with no signs of passage, east of the Bogda Chan Mountains (east of activity. Locations and activity signals indicate that bird Urumqi), crossing the Kazakhstan/China border 28132 died on its wintering ground on 13 November north of the Tien Shan Mountains (Fig. 2). The pre- 2003 and Houbara 28133 died on its breeding ground and post-breeding migration consistently followed on 4 April 2001. Eleven migration routes were recorded the same routes. (four pre-breeding and seven post-breeding). The post-breeding migrations of birds 20664 and 20672 Migration periods and travel rates were considered as incomplete as the birds’ transmitters had stopped before they reached their wintering Post-breeding migration departure dates ranged from quarters. 29 September to 14 October (n = 7, Table 2). None

Table 1. Houbara identity, start date, end date and duration of monitoring, number of locations used for analysis and of migration routes recorded.

Platform Transmission No. of locations used Ter minal No. of Transmitter Start End Period LC 1, 2 LC 0 migration (BIRD) no. date date Fate (days) and 3 and A routes

20664 05/13/00 11/30/00 death 201 119 20 *1 20672 05/15/00 10/12/00 hunted 150 87 7 *1 28132 05/15/00 11/13/03 death 1277 925 65 7 28133 05/15/00 04/28/01 death 348 297 28 2

*Houbara that did not complete their post-breeding migration.

346 J. Judas et al.

Figure 1. Migration routes and stopovers of three male Houbara Bustards (birds 20672, 20664 and 28133) captured in the Gobi Desert, China.

Table 2. Characteristics of pre- and post-breeding migrations of Houbara Bustard breeding in the Gobi Desert, China.

Distance Overall No. of Number Stopover Total Distance Migration per days migration short of long duration stopover Departure Arrival travelled duration Days travelled speed stopovers stopovers min.–max. duration BIRD date date (km) (days) travelled (km/day) (km/day) (< 7 days) (> 7 days) (days) (days)

Post-breeding 20664 10/06/00 – 3185 55 26 123 58 3 1 2–22 29 20672 09/24/00 – – – – – – – – – – 28133 10/02/00 10/23/00 3691 21 16 231 176 4 0 1–3 6 28132 10/12/00 11/03/00 3954 22 16 247 180 4 0 1–2 6 28132 10/08/01 11/01/01 4001 24 16 250 167 3 0 2–4 8 28132 10/14/02 10/27/02 4133 13 13 318 318 0 0 – 0 28132 10/12/03 11/07/03 4294 26 22 195 165 3 0 1–2 4 Pre-breeding 28133 03/21/01 04/17/01 3508 27 10 351 130 3 1 1–8 16 28132 03/07/01 04/21/01 3993 45 12 333 89 4 2 1–15 33 28132 03/02/02 04/11/02 3937 40 17 232 98 2 2 2–10 23 28132 03/02/03 04/18/03 3908 43 16 244 91 2 2 2–14 27

Migration and range use of Asian Houbara Bustard 347

Figure 2. Migration routes and stopovers of the male Houbara Bustard 28132 captured in the Gobi Desert, China, and satellite-tracked for three consecutive years. of the birds travelled together. For four successive distances exceeded 500 km in 16% of cases (29 of years, male 28132 regularly left its breeding ground 182 overall travelling days). As an example, bird between 8 and 14 October. From breeding to win- 28133 travelled 774 km in slightly more than 1 day tering areas, Houbara covered a mean distance of and bird 28132 covered 1082 km in less than 2 days 4014 ± 224 km (n = 5) in 21 ± 5 days (n = 5), but between the Taukum Desert and the Jungar Basin. In the effective number of days travelling (total travel this latter case, the average speed would have been time minus stopover times) was 17 ± 3 days (n = 5), 36 km/h, assuming continuous flight. with an average daily travel distance of 248 km. Arrival on the wintering grounds ranged from 23 October to Stopovers 7 November. Pre-breeding migration started between 2 and 21 March, with arrival dates of between 11 The birds had between zero and six stopovers during and 21 April, having travelled 3836 ± 222 km in their migrations (Table 2). In 2002, bird 28132 flew 39 ± 8 days (n = 4). The effective travelling time was its complete post-breeding migration (4132 km) in 14 ± 3 days with an average daily travel distance of 13 days without any stopover that exceeded 24 h. 290 ± 61 km (n = 4). Distances covered during pre- Removing this case, there were 3.6 ± 0.7 stopovers and post-breeding migration did not differ significantly (n = 2) and 4.3 ± 0.5 stopovers (n = 3) during pre- (U = 16, P = 0.142), nor did the effective travelling and post-breeding migrations, respectively. Stopo- durations (U = 6, P = 0.327) or the average daily travel vers lasted 4.1 ± 2.6 days (n = 5; range over the 36 distances (U = 13.5, P = 0.371), whereas the overall recorded stopovers was 2 h −22 days). Long stopovers migration duration did (U = 0, P = 0.014). Daily flight (> 7 days), as defined by Combreau et al. (1999),

Table 3. Characteristics of trans-country migration (distance travelled, ﬁrst and last dates of migration, mean number of days and sample size per country) of four Houbara Bustards captured in the Gobi Desert, China.

China Kazakhstan Uzbekistan Turkmenistan

Trans-country distance travelled (km) Mean (n) 1935 (11) 1391 (9) 374 (9) 324 (8) Post-breeding migration First – last dates 24/9–14/10 6/10–31/10 20/10–31/10 22/10–2/11 Mean time per bird, days (n) 13 (7) 6 (5) 2 (5) 2 (5) Time slot (days) 20 25 11 10 Pre-breeding migration First – last dates 25/3–3/4 6/3–22/3 5/3–21/3 2/3–21/3 Mean time per bird, days (n) 19 (4) 13 (4) 2 (4) 6 (4) Time slot (days) 27 28 17 19 Breeding/wintering First – last dates 14/4–12/10 24/10–19/3 Time (n) 155 (7) 128 (4)

were more frequent during pre-breeding inward its wintering quarters in Turkmenistan. Two and a migrations. Only one bird had a long stopover during half months (77.0 ± 18.5 days) were spent on migra- post-breeding migration, whereas all pre-breeding tion. The individual breeding season home range was migrations included at least one long stopover 274.2 ± 53.0 km2 on average for the four birds. In (Table 2). The 28 identified short stopovers were not 2000, all of them used a single core home range, localized on specific sites along the migration routes, whereas in the 2001 and 2002 breeding seasons, bird but never occurred in the mountainous areas between 28132 used three and two different areas, respectively. Urumqi and Lake Balkash. By contrast, the eight long The movements from one area to the other occurred stopovers occurred in only a few different areas, the at the end of the breeding season before migration Karakum Desert in Turkmenistan, the Muyunkum departure, from 9 August to 7 October 2001, and and Taukum deserts in Kazakhstan and mainly the from 22 July to 11 October 2002. The overall home- Jungar Basin in China (Figs 1 and 2). range overlap between the four Houbara caught on their breeding ground in 2000 was 59.7 ± 13.0% (151.6 ± 21.5 km2). Bird 28132, which was moni- Characteristics of trans-country tored for four consecutive breeding seasons, gradu- migration ally shifted its breeding home range from one season By mid-October all four birds had left China, and by to the other. The range overlap decreased from 73.8% early November had arrived on their wintering between 2000 and 2001 to no overlap between 2000 grounds in Turkmenistan (Table 3). The migration and 2003. segments in China and Kazakhstan lasted 20 and Wintering quarters were identified for birds 28132 25 days, respectively, during the post-breeding migra- and 28133. Bird 28133 wintered in Turkmenistan in tion, whereas crossing of Uzbekistan and Turkmenistan the Amu Darya valley, near the Uzbekistan border did not exceed 11 days. Time segments spent in each and had a 71-km2 wintering season home range. Bird country were longer during the pre-breeding migra- 28132 spent the 2000 winter 320 km away from tion, lasting, respectively, 27 and 28 days in China and Bird 28133, also in Turkmenistan but nearer the Iran Kazakhstan, where they had their long pre-breeding border. It used a 161-km2 wintering range in three stopovers. Flying through Turkmenistan and Uzbekistan distinct areas, separated by 8 km (between first and in spring took 19 and 17 days, respectively. By 21 second) and 70 km (between the second and third March the birds had left Turkmenistan, and arrived areas). Between 2000 and 2002, bird 28132 spent in China 1 month later. winters in the same region, but shrank (from 161 to 56 km2) and shifted its home range from one year to the other. Wintering home range in 2001 overlapped Range use on breeding and wintering its 2000 wintering home range by 0.6%. The home grounds range in winter 2002 overlapped the home range used Over 3 years, male 28132 spent 5.5 months (165.7 ± in winter 2001 by 35%, but completely excluded the 16.6 days) on its breeding ground in the Gobi Desert home range used in winter 2000, although these and approximately 4 months (122.3 ± 3.5 days) in latter two were only 4 km apart.

DISCUSSION Stopovers Short stopovers were distributed along migration Migration routes routes without any particular features, and were pre- During their post-breeding migration, the four satellite- sumably merely devoted to rest and feeding for a few tracked Houbara Bustards crossed China from the hours. Long stopovers occurred in four regions already Gobi Desert up to the Jungar Basin on an ill-defined identified as important for Houbara, either for breed- wide front. In the Jungar Basin, they joined routes ing or for staging (Combreau et al. 1999, Tourenq used by Houbara breeding in the north of Mongolia et al. 2005). The Jungar Basin was the most important and wintering in the Cholistan Desert of Pakistan staging area. Male 28132 stopped there for 10–15 (Tourenq et al. 2005). Several natural passes between days at the end of March during three consecutive the Jungar Basin and Kazakhstan, such as the Emel years and male 28133 for 8 days in early April 2001. valley (Tourenq et al. 2005), should channel migrant The other long stopovers occurred in the Muyunkum eastern Asian Houbara populations, as they turn and Taukum deserts of Kazakhstan, and the Karakum around the higher elevations of the Tien Shan Moun- Desert of Turkmenistan. The Kyzylkum Desert, tains. From the Taukum and Sary-Ishikotrau deserts, identified as an important staging site for Houbara the routes of the Gobi Desert breeding Houbara were breeding in the Taukum Desert and in north Mongolia, broadly similar to the paths used by north Mongolian was not used by the birds from Gobi. breeding Houbara (Combreau et al. 1999), passing Autumn migrations are often performed more slowly through Uzbekistan north to Turkmenistan. Overall, with more stages than spring migrations (Berthold their migration routes followed the distribution range 1996). Conversely, with the exception of bird 20664, of Houbara breeding populations along desert and which spent 22 days in the Muyunkum Desert in xeric shrub lands from eastern Asia to the Middle-East. autumn 2000, our Houbaras’ stopovers lasted longer These Chinese Gobi breeders migrating east–west in spring, so that their effective travelling time was spent the winter in areas that were used during the shorter. If refuelling was the main purpose of stopo- breeding season by other Houbara populations that vers, and as long as weather conditions were not too migrate further south in winter. The Karakum is thus different or adverse, we should have expected to both a wintering and a breeding area for different observe the same pattern during pre- and post-breeding populations that successively use the same site. Some migrations, and to record stopover durations more or Houbara may also be resident in Karakum. less proportional to the distances travelled. Although our data do not support this hypothesis, they might suggest that the Houbara is a capital breeder that Migration dates stores energy for reproduction during long pre-breeding Departure dates from the Gobi Desert in late stopovers. September–early October 2000 were similar to the Osborne et al. (1997) hypothesized that male departure dates recorded in Mongolia in 1998 and in Houbara could attempt to breed ‘en route’ by estab- the Xingjian Province of China between 1998 and lishing temporary display territories at stopovers to 2002 (NARC unpubl. data). In 1995, Houbara from attract local breeding females. In accordance with the Taukum Desert left their breeding grounds their lek-like breeding system (Hingrat et al. 2004), between late July and early September (Combreau males do not contribute to incubation and chick et al. 1999). The difference in departure dates could rearing, giving them the theoretical opportunity to be the result of annual variations; however, the extent mate during stopovers. Moreover, females can start of the difference (nearly 2 months) suggests this var- to lay eggs only 3–5 days post-arrival on their breed- iation to be related to the geographical origin of the ing grounds in China (Combreau et al. 2002). Given Houbara subpopulations. With monthly similar aver- a sperm storage ability of around 10 days (Gaucher age temperatures in both breeding areas, we would et al. 1996), females could also, potentially, copulate have predicted that birds living in more eastern areas during pre-breeding stopovers. The absence of would have left earlier because of the greater dis- important genetic variations in Asian Houbara popula- tance that they have to travel. By the time that the tions (Pitra et al. 2004) supports the hypothesis of an Houbara from the Gobi Desert crossed the Taukum exchange of genes ‘en route’ between populations Desert, the Houbara breeding there had been gone breeding east of the Aral Sea. As flapping-wing for nearly 2 months. migrants, particular wind conditions could also affect

departure dates from major stopovers sites before in most countries of the Houbara wintering range. crossing mountain regions or the huge peneplains In our small sample, bird 20672 was hunted on 14 of central Asia (Weber & Hedenström 2000, O. October 2000 in south Kazakhstan (reported by a Combreau pers. obs.). ring recovery at the Kazakh Institute); the activity sensor on bird 20664 stopped 110 km north, in the same continuous habitat, and this bird is likely also Range-use pattern to have been hunted. Bird 28132 was last located in The four Houbara studied were captured on the same Turkmenistan, where falconry is widely practised. breeding ground between 1 and 4 km from each Only the death of bird 28133 in China could not be other. Their wintering area was identified for two of definitively related to hunting. Given the important them, 370 km apart on either side of Turkmenistan. impact of hunting on Houbara populations, the The area used by bird 28132, on the border between implementation of a hunting regulation strategy and Uzbekistan and Turkmenistan, was previously recog- the creation of Protected Areas should be considered nized as the wintering quarters for one Houbara as high conservation priorities for this species. from the Taukum Desert (Combreau et al. 1999). The understanding of population connectivity is These results support both the view that migrant of major relevance for conservation issues (Webster Houbara populations, which were previously thought et al. 2002). With regard to migration routes from to be more separated (Osborne 1996), are substan- different breeding populations, Asian Houbara tially mixed and the view that there is weak migratory populations show a low degree of connectivity, but connectivity (sensu Webster et al. 2002) between a large geographical overlap. Hunting on stopovers breeding and wintering Houbara populations. Hou- and wintering grounds may affect many different bara breeding in the same area may winter in differ- breeding populations. The Taukum Desert and the ent areas, and vice versa. Apart from this, the data Jungar Basin, where different populations cross from bird 20132 suggest a strong individual fidelity together, can already be identified as key areas for to wintering and breeding areas. However, home Houbara conservation. However, the effects of sex, ranges of this adult male shifted slightly from year to age, geographical origin, meteorological conditions year both in winter and in spring and short range and food availability on migration pattern and the movements were recorded at the end of the breeding ecological significance of long stopovers still need to season before migratory departure. These local move- be addressed. The possibility that Houbara might ments could coincide with the utilization of habitats breed ‘en route’ during long stopovers and mix offering different food or different possibilities to genetically with different populations should be hide from predators during moulting, which occurs considered in order properly to appraise population from May to September (Saint-Jalme et al. 1996, dynamics in an evolutionary perspective. Jacquet 1998). The home ranges of these Gobi Desert Houbara were similar in size, and showed a similar We are grateful to HH Sheikh Hamdan bin Zayed Al reduction in range between breeding and wintering Nahyan, Deputy Prime Minister of the UAE and Chairman seasons to Houbara introduced to central Saudi of the board of the Environment Agency of Abu Dhabi (EAD), HH Sheikh Mansour bin Zayed Al Nahyan, Arabia (Combreau et al. 2000, J. Judas unpubl. data). Minister of Presidential Affairs and Vice Chairman of the However, this range-use pattern differed from the EAD board. We are especially grateful to HE Mohammed African Houbara in Morocco (Hingrat et al. 2004), Al Bowardi, Secretary General of Abu Dhabi Executive which have home ranges an order of magnitude smaller. Council and EAD Managing Director, and HE Majid Al Mansouri, EAD Secretary General, for their invaluable support. We thank colleagues from the Institute for Ecology Conservation implications and and Geography of Urumqi, Xinjiang Province, People’s perspectives Republic of China, without whom this study could not have been envisaged. I.R. Taylor and an anonymous referee Tourenq et al. (2005) reported a 17.5% decrease in are thanked for their comments on the manuscript. Houbara numbers per year between 1998 and 2002. Combreau et al. (2001) showed that this alarming trend was related to a high adult mortality rate, REFERENCES which was mainly due to poaching and over-hunting Argos. 1996. User’s Manual. Toulouse: CLS/Service Argos. by falconry. They considered the possible effects of Berthold, P. 1993. Bird Migration: a General Survey. Oxford: transmitters to be negligible. Falconry is practised Oxford University Press.

Berthold, P. 1996. Control of Bird Migration. London: Chapman tion of Birds. Circular 16. Washington, DC: US Department of & Hall. the Interior, US Fish and. Wildlife Service, and Jamestown, Britten, M.W., Kennedy, P.L. & Ambrose, S. 1999. Perform- ND: Northern Prairie Wildlife Research Center Home Page, ance and accuracy evaluation of small satellite transmitters. http://www.npwrc.usgs.gov/resource/othrdata/migratio/ J. Wildl. Manage. 63: 1349–1358. migratio.htm (Version02APR-2002). Collar, N.J. 1980. The world status of the Houbara: a preliminary Osborne, P.E. 1996. The Houbara Bustard in Arabia with special review. In Coles, C.L. & Collar, N.J. (eds) Proceedings of the reference to Abu Dhabi. In Osborne, P.E. (ed.) Desert Ecology Symposium on the Houbara Bustard Chlamydotis undulata. of Abu Dhabi: a Review and Recent Studies: pp. 86–97. Poole, UK: Sydenhams Printers. Newbury, UK: Pisces Publications. Collar, N.J. 1996. Family Otididae. In Del Hoyo, J., Elliot, A. & Osborne, P.E., Al Bowardi, M. & Bailey, T.A. 1997. Migration Sargatal, J. (eds) Handbook of the Birds of the World, Vol. 3 of the Houbara Bustard Chlamydotis undulata from Abu Hoatzin to Auks: 240–273. Barcelona: Lynx Edicions. Dhabi to Turkmenistan: the first results from satellite tracking Combreau, O., Gelinaud, G. & Smith, T.R. 2000. Home range studies. Ibis 139: 192–196. and movements of Houbara bustards introduced in the Nadj Pitra, C., D’Aloia, M.A., Lieckfelt, D. & Combreau, O. 2004. Genetic Pediplain in Saudi Arabia. J. Arid. Env. 44: 229–240. variation across the current range of the Asian Houbara Bustard Combreau, O., Launay, F., Al Bowardi, M. & Gubin, B. 1999. (Chlamydotis undulata macqueenii). Conserv. Genet. 5: 205 –215. Outward migration of Houbara Bustards from two breeding Saint-Jalme, M., Williams, J., Mickaelian, I. & Paillat, P. 1996. areas in Kazakhstan. Condor 101: 159–164. Seasonal variation of LH, Sex steroids, body mass, molt, Combreau, O., Launay, F. & Lawrence, M. 2001. An assessment display, and laying in two subspecies of Houbara Bustard, of annual mortality rates in adult-sized migrant Houbara Chlamydotis undulata macqueenii and Chlamydotis undulata bustards (Chlamydotis [undulata] macqueenii). Anim. Conserv. undulata, housed in outdoor cages under natural conditions. 4: 133–141. Gen. Comp. Endocrinol. 102: 102–112. Combreau, O., Qiao, J., Lawrence, M., Gao, X., Yao, J., Yang, W. Seaman, D.E. & Powell, R.A. 1996. An evaluation of the accu- & Launay, F. 2002. Breeding success in a Houbara Bustard racy of kernel density estimators for home range analysis. Chlamydotis [undulata] macqueenii population on the eastern Ecology 77: 2075–2085. fringe of the Jungar Basin, People’s Republic of China. Ibis Seddon, P.J., Saint-Jalme, M., Van Heezik, Y., Paillat, P., 14 (on-line): E45–E56. Gaucher, P. & Combreau, O. 1995. Restoration of Houbara Cramp, S. & Simmons, K.E.L. 1980. The Birds of the Western Bustard populations in Saudi Arabia: developments and Palearctic, Vol. 2. Oxford: Oxford University Press. future directions. Oryx 29: 136–142. ESRI. 1996. Using Arcview GIS. Redlands, CA: Environmental Shimazaki, H., Tamura, M. & Higushi, H. 2004. Migration Systems Research Institute, Inc. routes and important stopover sites of endangered oriental Gaucher, P., Saint-Jalme, M. & Paillat, P. 1996. Artificial insem- white storks (Ciconia boyciana) as revealed by satellite track- ination and natural mating. In Saint-Jalme, M. & Van Heezik, Y. ing. Mem. Natl Inst. Polar Res., Spec. Issue 58: 162–178. (eds) Propagation of the Houbara Bustard: 45–56. London: Times Books. 1998. The Times Atlas of the World: Comprehen- Kegan Paul International. sive Edition. London: Times Publication. Goriup, P. 1997. The world status of the Houbara Bustard Tourenq, C., Combreau, O., Lawrence, M., Pole, S.B., Spalton, A., Chlamydotis undulata. Bird Conserv. Int. 7: 373–397. Xinji, G., Al Baidani, M. & Launay, F. 2005. Alarming houbara Hays, G.C., Åkesson, S., Godley, B.J., Lusci., P. & Santidrian, P. bustard populations trends in Asia. Biol. Conserv. 121: 1– 8. 2001. The implications of location accuracy for the interpre- Upton, R. 1989. The Houbara Bustard and the Arab Falconer. tation of satellite-tracking data. Anim. Behav. 61: 1035–1040. Bustard Stud. 4: 174–176. Hingrat, Y., Saint-Jalme, M., Ysnel, F., Lacroix, F., Seabury, J. & Weber, T.P. & Hedenström, A. 2000. Optimal stopover decisions Rautureau, P. 2004. Relationships between home-range size, under wind influence: the effects of correlated winds. J. Theor. sex and season with reference to the mating system of the Biol. 205: 95–104. Houbara Bustard Chlamydotis undulata undulata. Ibis 146: Webster, M.S., Marra, P.P., Haig, S.M., Bensch, S. & Holmes, R.T. 314–322. 2002. Links between worlds: unraveling migratory connectivity. Hooge, P.N., Eichenlaub, W. & Salomon, E. 1999. The animal Trends Ecol. Evol. 17: 76–83. movement Program. Gustavus, Alaska: USGS, Alaska Biological Wilkinson, L., Engelman, L., Corter, J. & Corward, M. 2004. Science Center, http://www.absc.-usgs.gov/glba/gistools/ Cluster Analysis. In Systat 11 Statistics I. Richmond, CA: animal_mvmt.htm. Systat Software Inc. Jacquet, J.M. 1998. Seasonal changes in food intake and body Worldsat International Inc. 1997. LandSat view of the world. mass in captive Houbara bustards (Chlamydotis undulata) Mississauga, Ontario: Worldsat International Inc. and effect of ambient temperature. J. Arid Env. 38: 359–370. Worton, B.J. 1989. Kernel methods for estimating utilization Launay, F., Combreau, O. & Al Bowardi, M. 1999. Annual distribution in home-renge studies. Ecology 70: 164–168. migration of Houbara Bustard Chlamydotis undulata macqueenii from the United Arab Emirates. Bird Conserv. Int. 9: 155–161. Received 7 January 2005; Lincoln, F.C., Peterson, S.R. & Zimmerman, J.L. 1998. Migra- revision accepted 31 January 2006.