Asian Houbara Research Articles

Pathologic findings of acantholytic squamous cell carcinoma coexisting with cutaneous cryptococcosis in a Houbara bustard (Chlamydotis undulata)

A 2-year-old Asian Houbara bustard was presented with a solitary well-defined, firm cutaneous mass on the hock region. Grossly, the mass protruded from the surface was located on the hairless and unpigmented areas of the right hock joint with ulceration and dried hemorrhagic foci. On microscopic examination, ulceration, hemorrhage, as well as hyperkeratosis were observed. Large round, oval to polygonal neoplastic cells extended into the dermis were arranged to form cords, trabeculae, islands or glandular-like structures without keratin pearls. These pseudoglandular structures were composed of pseudolumina containing acantholytic and detached tumor cells. Necrosis of the neoplastic cells was accompanied by infiltration of inflammatory cells particularly heterophils. Unlike pleomorphic tumor cells, mitosis count was almost frequent. No evidence of other abnormalities and tumor metastasis was found. These gross and microscopic features appeared to be suggestive of a rare histologic variant of squamous cell carcinoma (SCC), acantholytic SCC.

Timing of Release Influence Breeding Success of Translocated Captive-Bred Migrant Asian Houbara Bustard

In conservation translocation, released animals should have comparable fitness to their wild counterparts to effectively contribute to the species demography. Captive-bred animals frequently exhibit lower fitness performances, which can often be attributed to an inadequate release strategy. Untimely release of migrant animals may interfere with key events such as their migration and breeding. In Kazakhstan and Uzbekistan, declining wild populations of Asian houbara (Chlamydotis macqueenii) are reinforced in their breeding grounds with captive-bred individuals. Using data from 6 years of monitoring, we compare eight breeding traits and the productivity of wild and captive-bred females released in two distinct seasons (autumn vs. spring) considering the effects of age and time in the season. Females released in the spring nest prior to their first migration, and females released in the autumn nest following their first migration. Our results highlight that captive-bred and wild females have similar breeding traits and productivity. Breeding probability, laying date, and egg volume varied, depending on the release season and female age. One-year-olds released in autumn have a significantly lower breeding probability compared to wild and spring-released females. However, 1-year-old females released in the spring nest later and lay smaller eggs than wild and autumn-released birds; effects which appear to be carried over with age. Age has a positive effect on breeding probability, egg volume, re-clutching probability and advancement of nesting date. These findings suggest a complex interplay of release timing with migration and breeding, resulting in short- and long-term effects on population demography, emphasizing its importance in conservation translocation.

Transnational Seasonal Land Grabbing in Pakistan: Power Positions and Resistance

Each year, the Ministry of Foreign Affairs (MoFA), Pakistan issues a special 10-day hunting permit to royal family members of Gulf countries for seasonal hunting of Asian Houbara bustard ( Chlamydotis macqueen). This paper attempts to systematically present the understandings on seasonal land grabbing and its political economy in Pakistan. The role of local elites and government institutions and the response of local people, as well as their resistance, is discussed in detail.

Birds use individually consistent temperature cues to time their migration departure.

A fundamental issue in migration biology is how birds decide when to start their journey, given that arriving too early or too late in a variable environment reduces individual fitness. Internal circannual regulation and predictable cues such as photoperiod prepare birds for migration, while variable external cues such as temperature and wind are thought to fine-tune departure times; however, this has not been demonstrated at the key point at which an individual animal decides to start migrating. In theory, environmental cues correlated between departure and arrival sites allow informed departure decisions. For 48 satellite-tracked Asian houbara Chlamydotis macqueenii, a medium-distance migrant with climatic connectivity between wintering and breeding areas, each tracked across multiple years, spring departure was under individually consistent temperature conditions, with greater individual repeatability than for photoperiod or wind. Individuals occupied a range of wintering sites latitudinally spanning 1,200 km but departed at lower temperatures from more northerly latitudes. These individual departure decisions produced earlier mean population-level departure and arrival dates in warmer springs. Phenological adjustments were fully compensatory, because individuals arrived on the breeding grounds under similar temperature conditions each year. Individuals' autumn departure decisions were also repeatable for temperature but less distinct than for spring, likely because of relaxed time constraints on leaving breeding grounds and the use of wind as a supplementary departure cue. We show that individual-level departure decisions informed by local temperatures can preadapt a population to adjust its population-level phenology in response to annual variability in spring temperatures without requiring genetic change in reaction thresholds.

Captive breeding and the conservation of the threatened houbara bustards

Translocation of captive-bred individuals to reinforce wild populations may be an important conservation approach for some species, but can be detrimental when employed to boost exploited wild populations, particularly where repeated long-term reinforcement aims to compensate for repeated unregulated offtake. We review evidence that captive breeding alters multiple physiological, life-history and temperamental traits through founder effects, genetic drift and unintended adaption to captivity; degrades learnt behaviours; and compromises biogeography, population structure and viability through introgression. We highlight these risks for the globally threatened African houbara Chlamydotis undulata and Asian houbara C. macqueenii, 2 bustard species hunted throughout much of their ranges and now subject to multiple large-scale captive-breeding programmes and translocations. In eastern Morocco, annual releases of captive-bred African houbara are 2‒3 times higher than original wild numbers, but no investigation of their potentially deleterious effects has, to our knowledge, been published, although most wild populations may now have been replaced by captive-bred domestic stock, which are reportedly not self-sustaining. Despite multiple decades of reinforcement, we are not aware of any analysis of the contribution of captive breeding to African houbara population dynamics, or of the genomic consequences. Asian houbara release programmes may also be promoting rather than preventing declines, and need to contextualise themselves through rigorous analyses of wild population numbers, demographic rates and threats, maintenance of phylogeographic concordance of released with supplemented populations, profiling of traits crucial to survival and the measurement and modelling of the impacts of reinforcement on physiological and behavioural fitness of wild populations.

Quantifying egg attendance behaviours of wild Asian houbara can improve artificial incubation outcomes

Artificial incubation is fundamental in ex situ avian conservation interventions for an increasing range of threatened species, but incubation parameters can differ between species. Both egg-turning angle and frequency are critical for successful embryonic development, but measuring these parameters in wild birds has historically been difficult. Using data-loggers inside artificial eggs that accurately record parental egg attendance behaviours, we quantified turning angles and rates throughout the incubation of 6 nesting wild Asian houbaras Chlamydotis macqueenii, a species bred in captivity in response to human over-exploitation. Wild females turned their eggs 0.6 times h-1 with a mean angle of 40.9° turn-1. Mimicking the patterns of wild birds (‘wild’ treatment), we applied a mean angular change of 40-50° turn once h-1 to artificially incubated eggs and compared this to eggs treated with an existing protocol (‘control’) of 120-130° per turn. Mean hatchability for the wild treatment (78.8%, n = 766) was similar to the control (76.6%, n = 1196). The wild treatment (n = 591) produced significantly heavier hatchlings (2.7%) than the control treatment (n = 893). However, chick growth rates (g d-1 and daily % mass change) and survival to Day 10 were not different between groups. The wild treatment demonstrates that turning angles affect embryo development and, perhaps, hatchability. Investigating natural incubation behaviours using egg-loggers and applying these patterns to artificial incubation appears efficacious to achieve optimal incubation protocols and reduce the need for ex situ trial and error refinement in conservation interventions of captive-bred threatened bird species.

Asian Houbara bustard male sexual maturity studies – preliminary results

Asian Houbara bustard male sexual maturity studies – preliminary results

The potential distribution of wintering and breeding populations of Asian Houbara Chlamydotis macqueenii in Iran

SummaryAsian Houbara Chlamydotis macqueenii is a vulnerable flagship species specific to steppe, desert and semi-desert habitats of the Middle East and Central Asia. Iran provides a critical corridor in the middle of Asian Houbara’s migratory route and also hosts a relatively large proportion of wintering and breeding populations. The aim of this study was to assess the distribution and habitat suitability of both wintering and breeding populations of Asian Houbara in Iran and evaluate the effectiveness of the existing protected area network for long-term protection of the species. For this purpose, 644 occurrence points for wintering and 216 points for breeding birds were collected from 17 Iranian provinces during 2015 to 2017. We then used a consensus species distribution modelling (SDM) approach using 11 uncorrelated environmental variables to explore the distribution of Asian Houbara habitats. Results showed that climatic and topographic variations have the most significant influence on the regional-scale distribution of Asian Houbara. Of the suitable habitats recognised for the wintering and breeding populations, 40.6% and 29.6% respectively overlapped with the extent of the protected network. A high level of spatial niche similarity (78%) was observed between wintering and breeding populations. The central, eastern and south-central Iranian semi-arid regions and desert landscapes hosted the majority of both wintering and breeding houbara occurrences. Results of this study could be used for adopting direct management planning and raising the protection level of important no-hunting areas.

Releases of Asian houbara must respect genetic and geographic origin to preserve inherited migration behaviour: evidence from a translocation experiment.

Maintaining appropriate migratory strategies is important in conservation; however, translocations of migratory animals may alter locally evolved migration behaviours of recipient populations if these are different and heritable. We used satellite telemetry and experimental translocation to quantify differences and assess heritability in migration behaviours between three migratory Asian houbara (Chlamydotis macqueenii) breeding populations (640 km range across eastern, central and western Uzbekistan). Adults from the eastern population migrated twice as far (mean = 1184 km ± 44 s.e.) as the western population (656 km ± 183 s.e.) and showed significantly less variation in migration distance than the central population (1030 km ± 127 s.e.). The western and central populations wintered significantly further north (mean: +8.32° N ± 1.70 s.e. and +4.19° N ± 1.16 s.e., respectively) and the central population further west (−3.47° E ± 1.46 s.e.) than individuals from the eastern population. These differences could arise from a differing innate drive, or through learnt facultative responses to topography, filtered by survival. Translocated birds from the eastern population (wild-laid and captive-reared, n = 5) migrated further than adults from either western or central recipient populations, particularly in their second migration year. Translocated birds continued migrating south past suitable wintering grounds used by the recipient populations despite having to negotiate mountain obstacles. Together, this suggests a considerable conserved heritable migratory component with local adaptation at a fine geographic scale. Surviving translocated individuals returned to their release site, suggesting that continued translocations would lead to introgression of the heritable component and risk altering recipient migration patterns. Conservation biologists considering translocation interventions for migratory populations should evaluate potential genetic components of migratory behaviour.

Backpack-mounted satellite transmitters do not affect reproductive performance in a migratory bustard

Backpack-mounted satellite transmitters (PTTs) are used extensively in the study of avian habitat use and of the movements and demography of medium- to large-bodied species, but can affect individuals’ performance and fitness. Transparent assessment of potential transmitter effects is important for both ethical accountability and confidence in, or adjustment to, life history parameter estimates. We assessed the influence of transmitters on seven reproductive parameters in Asian houbara Chlamydotis macqueenii, comparing 114 nests of 38 females carrying PTTs to 184 nests of untagged birds (non-PTT) over seven breeding seasons (2012–2018) in Uzbekistan. There was no evidence of any influence of PTTs on: lay date (non-PTT x̅ = 91.7 Julian day ± 12.3 SD; PTT x̅ = 95.1 Julian day ± 15.7 SD); clutch size (non-PTT x̅= 3.30 ± 0.68 SD; PTT x̅ = 3.25 ± 0.65 SD); mean egg weight at laying (non-PTT x̅ = 66.1 g ± 5.4 SD; PTT x̅ = 66.4 g ± 5.4 SD); nest success (non-PTT x̅ = 57.08% ± 4.3 SE; PTT x̅ = 58.24% ± 4.5 SE for nests started 2 April); egg hatchability (non-PTT x̅ = 88.3% ± 2.2 SE; PTT x̅ = 88.3% ± 2.6 SE); or chick survival to fledging from broods that had at least one surviving chick (non-PTT x̅ = 63.4% ± 4.2 SE; PTT x̅ = 64.4% ± 4.7 SE). High nesting propensity (97.3% year−1 ± 1.9% SE) of tagged birds indicated minimal PTT effect on breeding probability. These findings show that harness-mounted transmitters can give unbiased measures of demographic parameters of this species, and are relevant to other large-bodied, cursorial, ground-nesting birds of open habitats, particularly other bustards.

Short-term Land Acquisition, Long-term Impacts: The Case of Houbara Bustard Hunting in South Punjab, Pakistan

Pakistan provides seasonal hunting permits to the rulers of Gulf countries for hunting of Asian Houbara bustard ( Chlamydotis macqueenii) in different parts of the country. This research deals with (transnational) seasonal land acquisition of different rangelands/deserts of the Punjab province of Pakistan. So far, no comprehensive research has been conducted in Pakistan on this issue. This research attempts to address the impact of seasonal land grabbing by the foreigners on livelihood assets of local stakeholders in South Punjab, Pakistan. Based on the idea of ‘control grabbing’, this research uses ‘sustainable livelihood framework’ as an analytical framework. Quantitative and qualitative data were acquired from three (out of a total nine) randomly selected hunting sanctuaries in the districts of Rajanpur and Dera Ghazi Khan. The results revealed that natural assets of local population (agricultural land and rangeland) are adversely affected during the entire hunting season. Limited access to natural assets (especially livestock fodder) has long-term negative impacts on livelihood diversification of the locals as the number of livestock – one of the most important assets of respondents – is continuously decreasing in the case study area. We recommend that land enclosure should be restricted to a limited area for a limited time, and that the Government should develop an effective monitoring and evaluation system.

Captive breeding cannot sustain migratory Asian houbara Chlamydotis macqueenii without hunting controls

To evaluate the potential contribution of captive breeding to the conservation of exploited migratory Asian houbara Chlamydotis macqueenii, we estimated release numbers required to stabilise a population in a hunting concession (14,300 km2), under scenarios of local licensed hunting and flyway-scale protection. We developed a population model, initially 2350 adult females, re-sampling parameters measured through fieldwork and satellite telemetry, over 1000 iterations. With current flyway-scale unregulated harvest, and without any licensed hunting in the concession, populations declined at 9.4% year−1 (95% CI: −18.9 to 0% year−1); in this scenario a precautionary approach (85% probability λ ≥ 1.0) to population stabilisation required releasing 3100 captive-bred females year−1 (131% of initial wild numbers). A precautionary approach to sustainable hunting of 100 females year−1 required releasing 3600 females year−1 (153% of initial wild numbers); but if interventions reduced flyway-scale hunting/trapping mortality by 60% or 80%, sustaining this quota required releasing 900 or 400 females year−1, 38% and 17% of initial wild numbers, respectively. Parameter uncertainty increased precautionary numbers for release, but even with reduced precaution (50% probability λ ≥ 1.0), sustainable hunting of 100 females year−1 required annual releases of 2200 females (94% wild) without other measures, but 300 (13%) or no (0%) females under scenarios of a 60% or 80% reduction in flyway-scale hunting/trapping. Captive breeding cannot alone sustain migrant populations of wild C. macqueenii because it risks replacement and domestication. Trade and exploitation must be restricted to avoid either extinction or domestication. For exploited populations, supplementation by captive breeding should be used with caution.

Consistent nest-site selection across habitats increases fitness in Asian Houbara

ABSTRACT Nest-site choice profoundly influences reproductive success and the survival of incubating adult birds. Asian Houbara (Chlamydotis macqueenii) nest in subtly contrasting habitats where the main cause of nest failure is predation. We examined nest-site selection across 3 semiarid shrub habitats that differed in vegetation structure and hypothesized that increased concealment would reduce nest predation. We quantified vegetation structure at 210 nests and 194 random control sites at 2 scales, the “nest area” (50 m radius, considering mean “shrub height” and mean “shrub frequency”) and “nest scrape” (2 m radius, considering a “concealment index”). Variance ratio tests showed that variance in both shrub height and concealment index was lower at nests than at random sites, indicating nonrandom selection. Analysis of the probability of nest occurrence for nest area indicated consistent selection of intermediate shrub heights (shrub height + shrub height2) in the Astragalus, Salsola arbuscula, and S. ri...

Seasonal evaluation habitat of Asian Houbara in the Central and East Iran

The Asian Houbara is vulnerable species, the population of which is dwindling. Its protection must be prioritized in conservation programs. In this study, maximum entropy models were developed in four seasons to evaluate habitat suitability and factors affecting Asian Houbara in the Center and East Iran. Environmental variables used in modeling and evaluating the niche consisted of 24 environmental and climate variables for Gharetapeh hunting prohibited region and 36 environmental and climate variables for Petregan protected area. Also, seasonal overlap area was obtained using the ENM TOOLS software. The results showed that the most important factors affecting habitat suitability of the Asian Houbara in all seasons included the ratio of distance to the type of Artemisia sieberi–Zygophyllum eurypterum, distance to the slope 2–5%, distance to the type of Seidlitzia rosmarinus in the Gharetapeh hunting prohibited region, distance to the type of Artemisia aucheri, distance to the land passion, and distance to the dry land farming in the Petregan region. In summer and fall–winter, the most suitable habitat is Gharetapeh but is Petergan during fall–winter. There is maximum overlap in fall and winter, and the least overlap in the spring in these areas.

Rainfall validates MODIS-derived NDVI as an index of spatio-temporal variation in green biomass across non-montane semi-arid and arid Central Asia

As satellite-derived normalized difference vegetation index (NDVI) is related to vegetation biomass, it may provide a proxy for habitat quality across extensive species ranges where ground-truth data are scarce. However, NDVI may have limited accuracy in sparsely-vegetated arid and semi-arid environments due to signal contamination by substrate reflectance. To validate NDVI as a vegetation proxy in the low-altitude deserts of Central Asia, we examine its response to precipitation across the migratory corridor of Asian Houbara Chlamydotis macqueenii, a threatened gamebird occupying deserts from the Middle East to China. Restricting NDVI data by altitude (masking higher elevations unoccupied by n = 61 satellite-tracked houbara) and 2009 Globcover land cover (excluding cropland and built-up area), we relate moderate-resolution imaging spectroradiometer (MODIS) NDVI data to Global Precipitation Climatology Project precipitation data across five World Wildlife Fund semi-arid ecoregions (totaling 4.06 million km2). We examine this both spatially (per 1°cell, mean annual NDVI and mean precipitation over 16 years, 2000–2015); and temporally (annual NDVI and annual precipitation) using separate temporal General Linear Models per cell and an overall Generalized Linear Mixed Model (GLMM) (including cell ID as a random effect). We sought to explain spatial variation in the NDVI-precipitation relation among temporal per degree-cell models, in terms of the slope (strength) and adjusted (adj.) R2 (explanatory power), using inter-annual mean NDVI (2000–2015) and Gridded Livestock of the World livestock density. NDVI increases with precipitation, both spatially (adj. R2 = 0.58, p < 0.001) and temporally (mean adj. R2 across n = 244, 1° cells = 0.44; GLMM across cells p < 0.001). More vegetated regions show a stronger temporal response of vegetation biomass for a given precipitation increment (slope of NDVI to precipitation in per cell temporal models increases with inter-annual mean NDVI; adj. R2 = 0.38, p < 0.001), reinforcing the conclusion that NDVI provides a proxy for vegetation abundance. The slope of this relation did not differ among ecoregions. Although livestock density is generally assumed to degrade vegetation and weaken the NDVI-precipitation relationship, explanatory power (adj. R2 of per cell NDVI-precipitation models) is weakly, but positively, related to livestock density (adj. R2 = 0.02, p = 0.011). This may be because we assess livestock at a coarse grain, at scales where overall stocking density is positively associated with vegetation abundance, but may also indicate that livestock are not degrading vegetation at regional landscape-scales despite potential localized effects. The strong signature of rainfall shows MODIS NDVI offers a potentially powerful proxy for spatial and temporal variation in arid and semi-arid vegetation at a resolution of 1° and 1 year over the houbara's breeding and wintering range, and probably also at finer spatial resolutions. NDVI can therefore be used in analyses relating (a) staging and wintering site selection to variation in habitat among potential wintering locations, and (b) variation within and between localities to demographic carry-over effects.

Comparative migration strategies of wild and captive‐bred Asian Houbara Chlamydotis macqueenii

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.

Breeding success and juvenile survival in a reintroduced captive-bred population of Asian houbara bustards in the United Arab Emirates

Breeding success and juvenile survival in a reintroduced captive-bred population of Asian houbara bustards in the United Arab Emirates

Habitat suitability and impacts of climate change on the distribution of wintering population of Asian Houbara BustardChlamydotis macqueeniiin Iran

SummaryWe developed a habitat suitability model for wintering populations of the Asian Houbara BustardChlamydotis macqueeniiin Iran and determined environmental variables affecting its occurrence. Our results indicate that various patches in central, western and eastern Iran provide the most suitable habitats for the Houbara. Annual precipitation, slope and distance to croplands were the most important variables for predicting Houbara occurrence. We also determined the effects future climate changes on the distribution of the Houbara in Iran. Results showed that suitable habitats for the wintering Houbara will increase in Iran, but will also considerably shift under future climatic conditions. The distribution maps that we present for the present and future climatic conditions can have important implications for the conservation and management of Houbara populations in Iran.

The Influence of Environmental Factors on the Distribution of Wintering Populations of Asian Houbara Bustard Chlamydotis Macqueenii in Central Iranian Plateau

The Influence of Environmental Factors on the Distribution of Wintering Populations of Asian Houbara Bustard Chlamydotis Macqueenii in Central Iranian Plateau

Seasonal habitat suitability modeling and factors affecting the distribution of Asian Houbara in East Iran.

In this study, maximum entropy models were developed in four seasons to evaluate habitat suitability and factors affecting Asian Houbara in Iran. Environmental variables used in modeling consisted of 42 environmental and climate variables for Nayband wildlife refuge and 36 environmental and climate variables for Petregan protected area. Also, seasonal overlap area were obtained using the ENM TOOLS software. The results showed that the most important factors affecting habitat suitability of the Asian Houbara in all seasons included the ratio of distance to hill, the type of Artemisia−Gymnocarpus, distance to the slope (8–12%) in the Nayband wildlife refuge, distance to the type of Artemisia aucheri, distance to the Land Passion, and distance to the dry land farming in the Petregan region. In summer, the most suitable habitat is Nayband but is Petergan during fall-winter. there is maximum overlap in summer, and the least overlap in the spring these areas. The results of this study can be used as a valuable tool in implementing conservation and management strategies, in order to increase desirable habitats in the eastern part of Iran.