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For migratory species, the success of population reintroduction or reinforcement through captive-bred released individuals depends on survivors undertaking appropriate migrations. We assess whether captive-bred Asian Houbara Chlamydotis macqueenii from a breeding programme established with locally sourced individuals and released into suitable habitat during spring or summer undertake similar migrations to those of wild birds. Using satellite telemetry, we compare the migrations of 29 captive-bred juveniles, 10 wild juveniles and 39 wild adults (including three birds first tracked as juveniles), examining migratory propensity (proportion migrating), timing, direction, stopover duration and frequency, efficiency (route deviation), and wintering and breeding season locations. Captive-bred birds initiated autumn migration an average of 20.6 (±4.6 se) days later and wintered 470.8 km (±76.4) closer to the breeding grounds, mainly in Turkmenistan, northern Iran and Afghanistan, than wild birds, which migrated 1217.8 km (±76.4), predominantly wintering in southern Iran and Pakistan (juveniles and adults were similar). Wintering locations of four surviving captive-bred birds were similar in subsequent years (median distance to first wintering site = 70.8 km, range 6.56-221.6 km), suggesting that individual captive-bred birds (but not necessarily their progeny) remain faithful to their first wintering latitude. The migratory performance of captive-bred birds was otherwise similar to that of wild juveniles. Although the long-term fitness consequences for captive-bred birds establishing wintering sites at the northern edge of those occupied by wild birds remain to be quantified, it is clear that the pattern of wild migrations established by long-term selection is not replicated. If the shorter migration distance of young captive-bred birds has a physiological rather than a genetic basis, then their progeny may still exhibit wild-type migration. However, as there is a considerable genetic component to migration, captive breeding management must respect migratory population structure as well as natal and release-site fidelity. [ABSTRACT FROM AUTHOR]

ABSTRACT Increasing knowledge of post-release survival and habitat requirements of translocated animals is critical to improve success of conservation programs. We estimated survival of reintroduced captive-bred Asian houbara bustards ( Chlamydotis macqueenii) in reserves of western United Arab Emirates where plantations exist as supplementary feeding sites. We explored factors influencing short- (3 months after release) and long-term (tri-monthly periods after third month of release) survival rates of released birds. We modeled life histories of individually tracked houbara using Program MARK. Mean short-term survival probability (0.76 ± 0.14 SD) was lower than mean long-term survival (0.86 ± 0.03 SD), and observed group size and the age of released birds positively correlated with short-term survival. We hypothesize that higher quality habitat (plantations) affected survival; larger groups occurred in plantations and older birds might be better able to maintain access to plantations. Long-term survival was negatively influenced by subsequent release events. Releasing more individuals increases local houbara density. This may lead to food depletion, increase in density-dependent mechanisms between individuals, or both. Short- and long-term survival rates suggest that food availability at the release sites, together with intraspecific interactions, may influence survival of newly released and established individuals. To improve the management of translocated animals, the impact of managed food resources should be quantified to assess how it might affect population vital rates. © 2016 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Asian Houbara Chlamydotis macqueenii numbers are declining as a result of unsustainable levels of hunting and poaching, with the main conservation response being population reinforcement through the release of captive-bred birds. We assessed the contribution of captive breeding to the species' conservation by examining the fates of 65 captive-bred birds fitted with satellite transmitters and released during spring (March-May) and autumn (August) into breeding habitat in Uzbekistan. Of the released birds, 58.5% survived to October, the month favoured by Emirati hunters in Uzbekistan, but only 10.8% of those released survived the winter to return as subadults next spring. To mitigate and compensate for the loss of wild adults to hunting, the number of released birds needs to be an order of magnitude higher than hunting quotas (with a release of between 1640 and 1920 required for a hypothetical quota of 200), indicating that releases may be costly and do not remove the need for a biologically determined sustainable hunting quota. [ABSTRACT FROM AUTHOR]

For endangered species that are hunted, the establishment of mixed conservation areas including both hunting zones and sanctuaries to complement translocation actions (i.e. reinforcement) can improve both hunting yields and population sustainability. However, the effects of this type of management on the demography of the exploited species are not well understood. We used multi-event capture-recapture modelling in a population of captive-bred houbara bustards C hlamydotis undulata translocated into a mixed conservation area in Morocco. The specific management practice of our system (hunting regime varying in time and space) led to a quasi-experimental situation that allowed the differentiation of 'natural' from 'hunting-induced' mortality and movement between areas. The analysis uncovered strong asymmetries in both movement and survival that were not only due to direct hunting effects. Firstly, movement probabilities were higher from the sanctuary to the hunting areas than vice versa, even in years without hunting. Secondly, in addition to a direct effect of hunting on mortality in hunting areas, our results uncovered permanent differences in both areas (even outside the hunting period). Overall, our results were consistent with predictions under a source-sink dynamic model but illustrated that mixed conservation areas should not merely be treated as homogeneous systems with spatially heterogeneous hunting pressure but rather as fully heterogeneous systems. The patterns observed may be related to (1) the choice and design of hunting and sanctuary areas by managers, which might not be neutral with respect to habitat quality, or (2) indirect consequences of hunting via an effect on local growth rate and density. [ABSTRACT FROM AUTHOR]

A high immediate mortality rate of released animals is an important cause of translocation failure ('release cost'). Post-release dispersal (i.e. the movements from the release site to the first breeding site) has recently been identified as another source of local translocation failure. In spite of their potential effects on conservation program outcomes, little is known about the quantitative effects of these two sources of translocation failure and their interactions with environmental factors and management designs., Based on long-term monitoring data of captive-bred North African houbara bustards Chlamydotis undulata undulata (hereafter, houbara) over large spatial scales, we investigated the relative effects of release (e.g. release group size, period of release), individual (e.g. sex and body condition) and meteorological (e.g. temperature and rainfall) conditions on post-release survival ( n = 957 individuals) and dispersal ( n = 436 individuals)., We found that (i) rainfall and ambient air temperature had, respectively, a negative and a positive effect on houbara post-release dispersal distance; (ii) in interaction with the release period, harsh meteorological conditions had negative impact on the survival of houbara; (iii) density-dependent processes influenced the pattern of departure from the release site; and (iv) post-release dispersal distance was male-biased, as natal dispersal of wild birds (although the dispersal patterns and movements may be influenced by different processes in captive-bred and in wild birds)., Synthesis and applications. Our results demonstrate that post-release dispersal and mortality costs in translocated species may be mediated by meteorological factors, which in turn can be buffered by the release method. As the consequences of translocation programs on population dynamics depend primarily upon release costs and colonization process, we suggest that their potential interactions with meteorological conditions must be carefully addressed in future programs (i) through monitoring of short-term post-release mortality to understand its link with environmental conditions, (ii) by carefully choosing the season of release to minimize exposition of inexperienced individuals to harsh conditions and (iii) by generalizing the use of long-term weather forecast to adapt release effort and staggering releases over several years to buffer meteorological effects. [ABSTRACT FROM AUTHOR]

Selection pressures acting on both intrasexual competition and intersexual relationships may lead to the emphasis of individual variation and might thus lead to the expression of individual signature. This is particularly true in lek mating systems, where providing information on identity and/or quality to potential mates or congeners of the same sex can be essential for individuals to optimize their reproductive success. Visual and acoustic signals produced during the courtship of the lekking North African Houbara bustard ( Chlamydotis undulata undulata), based on field data from wild birds, are investigated here for the first time. Results show that the vocal signals, called booms, are characterized by a very low frequency, a rare phenomenon in birds which should allow booms to propagate over long distances. Results also show that both visual and acoustic signals are individualized and stereotyped between males. Using three methods of analysis, we highlight the acoustic parameters likely to support vocal individual signature and show that such information mainly relies on frequency parameters. [ABSTRACT FROM AUTHOR]

In light of widespread declines of houbara bustard Chlamydotis macqueenii populations across its extant range, captive breeding has emerged as a viable option for regenerating viable populations of houbaras in addition to limiting hunting pressure, habitat management and amelioration of predation pressure. Although reintroductions of captive-bred houbaras have been carried out in many regions in recent years, information on differences in ranging behavior and habitat selection between captive-bred and wild-born houbaras is lacking. In this study, we utilized radiotelemetry data spanning 13 years to assess differences in home range use and habitat selection by houbara bustards in the Mahazat as-Sayd reserve in Saudi Arabia. The mean (±standard error of the estimate) annual home range size, estimated using the Kernel density method, was 307.76 ± 15.91 km2, and did not differ significantly between genders. Annual home ranges of wild-born houbaras were however larger than those of their captive-born counterparts (wild-born: 423.77 ± 62.66 km2, captive-bred: 299.31 ± 16.39 km2). Rainy season home ranges were the largest (279.29 ± 27.75 km2) followed by winter home ranges (245.79 ± 19.19 km2) and summer home ranges (110.51 ± 8.91 km2) indicating larger-scale movements of houbaras when forage was available. Seasonal home ranges did not differ significantly between wild-born or captive-bred houbaras. Analysis of habitat selection patterns using the distance-based method revealed consistent patterns of habitat preferences across years and seasons and between genders, ages and whether the bird was captive-bred or wild-born. Results indicate that scrub forms the most preferred habitat for houbaras, and should be conserved for the population welfare of the houbara in Saudi Arabia. [ABSTRACT FROM AUTHOR]

Habitat selection is a hierarchical process where the distribution of individuals is constrained by environmental factors acting from the landscape scale to specific microhabitats such as breeding sites. However, interactions between conspecifics might greatly influence bird distribution and habitat use, especially in lekking birds. In the lekking Houbara bustard Chlamydotis undulata undulata, we investigated the respective role of environmental and social constraints on the distribution of nests and display sites. We measured environmental variables around 69 nests and 70 display sites at different spatial scales: the landscape, the breeding range, and the display and nest site scale. The variables were compared to those measured at 50 random plots to determine whether environmental features are actively selected. Social variables were included by studying spatial relationships between displaying male density, nests and female movements throughout the year. At the landscape scale, human presence acted as a limiting factor for the establishment of nest and display sites. At the breeding range scale, habitat requirements differed between sexes. Breeding females used a heterogeneous complex of habitats provided by the network of wadis (water courses) crossing the reg (gravel plain) covered by tall perennial plants. In contrast, display males looked for conspicuousness and courtship ability by selecting the reg with short perennials, and used temporarily flooded areas for feeding. Males aggregated on traditional display site where they experienced the greatest female density. This result supported the hotspot model in the evolution of leks in the Houbara bustard. It underlies an overriding effect of female attraction on male settlement in the individual habitat selection process. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The distribution and global habitat association of the North African houbara bustard (Chlamydotis undulata sensu stricto) were studied for the first time in a large semi-arid steppe-land region in eastern Morocco. The study area has been protected from hunting for 6 years, but was still under significant pressure from grazing activities. Houbara distribution was assessed using point count surveys conducted during the 2002 breeding season and compared to natural- and human-related predictors. The hierarchy and quantification of influences was evaluated using a discriminant function analysis. Micro-topography first drove houbara bustard distribution, since birds were usually found in open flat tracts allowing visibility over a long distance for the prevention of potential predator approaches, but also for breeding males to be seen by conspecifics. 'Flooding surfaces' presenting concealment possibilities, as well as readily available food resources, were secondly sought. Proximity to wells was a surrogate to human presence and pastoral activity influences and appeared to affect houbara bustard distribution. The weight of human disturbance on houbara distribution is highlighted and it is recommended that this should be considered in conservation plans. [ABSTRACT FROM AUTHOR]

This paper presents observations of Houbara BustardChlamydotis undulata undulatahome-range, in the semi-desert steppe of eastern Morocco. Home-ranges were calculated from radiotagged birds using the fixed kernel method (LSCV). The mean annual home-range of males (17 km2) was smaller than that of females (146 km2;P < 0.001). The majority of male home-ranges had a unimodal distribution (86%), whereas 67% of female home-ranges were multimodal. Consequently, the amplitude of female movements was larger (mean: 44 km/13 km;P < 0.002). In spring, male home-ranges decreased in size around display sites (8 km2) and many of them overlapped considerably. Display sites show an aggregative distribution (P < 0.001) and a single female reproductive range may contain the display sites of several males. The data fulfil the definition of an exploded lek social structure. In our study,C. u. undulataappears to be sedentary with relatively limited home-ranges. Successive years of fidelity to home-ranges indicate that adults are not nomadic. [ABSTRACT FROM AUTHOR]

Investigates the influence of climate, age and egg-laying experience on reproductive performance of a flock of captive houbara bustards in Saudi Arabia. Influence of winter temperatures on reproduction; Comparison between first-time egg-layers and females with previous egg-laying experience.

Studies the migration and behavioral ecology of houbara bustard or Chlamydotis undulata, by adapting different capture methods for use during the breeding season. Description of the study area; Capture methods for displaying males, nesting females and immatures or non-breeding males and females; Results of the study; Conclusions.

The in-vitro activity of enrofloxacin against 117 strains of bacteria isolated from bustards was determined. Minimum inhibitory concentrations for 72% of the Proteus spp., E. coli, Salmonella spp. and Klebsiella spp. (n = 61) and for 48% of the Streptococci spp. and Staphylococci spp. (n = 31) were <= 0.5 μ g/mL. The minimum inhibitory concentration (MIC) of 76% of Pseudomonas spp. (n = 25) was < 2 μg/mL. Fourteen strains were resistant to concentrations > 128 μg/mL. The elimination half-lives (t½ elim β) (mean± SEM) of 10 mg/kg enrofloxacin in eight houbara bustards (Chlamydotis undulata) were 6.80± 0.79, 6.39± 1.49 and 5.63± 0.54 h after oral (p.o.), intramuscular (i.m.) and intravenous (i.v.) administration, respectively. Enrofloxacin was rapidly absorbed from the bustard gastro-intestinal tract and maximum plasma concentrations of 1.84± 0.16 μg/mL were achieved after 0.66± 0.05 h. Maximum plasma concentration after i.m. administration of 10 mg/kg was 2.75± 0.11 μg/mL at 1.72± 0.19 h. Maximum plasma concentration after i.m. administration of 15 mg/kg in two birds was 4.86 μg/mL. Bioavailability was 97.3± 13.7% and 62.7± 11.1% after i.m. and oral administration, respectively. Plasma concentrations of enrofloxacin >= 0.5 μg/mL were maintained for at least 12 h for all routes at 10 mg/kg and for 24 h after i.m. administration at 15 mg/kg. Plasma enrofloxacin concentrations were monitored during the first 3 days of treatment in five houbara bustards and kori bustards (Ardeotis kori) with bacterial infections receiving a single daily i.m. injection of 10 mg/kg for 3 days. The mean plasma enrofloxacin concentrations in the clinical cases at 27 and 51 h (3.69 and 3.86 μg/mL) and at 48 h (0.70 μg/mL) were significantly higher compared with the 3 h and 24 h time intervals from clinically normal birds. The maximum plasma concentration (Cmax)/MIC ratio was ranked i.v. (10/mg/kg) > i.m. (15 mg/kg) > i.m. (10 mg/kg) > oral (10 mg/kg), but it was only higher than 8:1 for i.v and i.m. administrations of enrofloxacin at 10 mg/kg and 15 mg/kg, respectively, against a low MIC (0.5 μg/mL). A dosage regimen of 10 mg/kg repeated every 12 h, or 15 mg/kg repeated every 24 h, would be expected to give blood concentrations above 0.5 μg/mL and hence provide therapeutic response in the bustard against a wide range of bacterial infections. [ABSTRACT FROM AUTHOR]