Black-bellied Sandgrouse Research Articles

Using GPS and accelerometer data to remotely detect breeding events in two elusive ground-nesting steppe birds

BackgroundModern biologging technologies allow researchers to gain a better understanding of animal movements, offering opportunities to measure survival and remotely study the breeding success of wild birds, i.e., by locating nests. This is particularly useful for species whose nests are difficult to find or access, or when disturbances can impact the breeding outcome. We developed and validated, with field data, a framework to detect nesting events by two sandgrouse species, the black-bellied (Pterocles orientalis) and pin-tailed sandgrouse (Pterocles alchata), using GPS and Overall Dynamic Body Acceleration (ODBA) data. Sandgrouses are ground-nesting, cryptic, and elusive birds with biparental incubation efforts. Because both sexes take turns to incubate, a novel framework considering when tagged individuals are on incubation duty or not needs to be designed to detect nests.ResultsWe tagged 52 birds with high-resolution GPS devices to monitor their breeding during 2021–24. Using remote tracking and field data from the first 2 years (2021–22), we first determined sex-specific time windows for incubation to maximise differentiation between incubation and non-incubation behaviours. We then used a threshold-based classification to identify incubation days and inferred the minimum number of successive incubation days needed to correctly identify a nesting event. We show how ODBA and GPS data can be used to successfully detect nests incubated for only 2 or 3 days. GPS-only data or combined GPS-ODBA data had a success rate of around 95%, whereas ODBA-only data had a success rate of 100%. Cross-validation using data from 2023 to 2024 confirmed the model’s performance, showing an overall success > 90% for GPS-only and ODBA-only data and of 85% for combined GPS–ODBA data.ConclusionsBy accurately identifying nesting events, our framework offers new opportunities to study the breeding of conservation-dependent species. Besides its applicability to ground-nesting species with biparental care and sex-specific incubation schedules, the framework can be adapted to other bird species sensitive to disturbances or with inaccessible nesting sites. By doing so, it reduces the need for nest visits and associated disturbances, as well as the carbon footprint and expenses associated with fieldwork.

Early Neolithic avifaunal remains from southeast Anatolia provide insight into Early Holocene species distributions and long‐term shifts in their range

Based on the species‐rich avifaunas from Early Neolithic sites across Upper Mesopotamia (southeast Türkiye, northern Syria, northern Iraq), we compared seven species' Early Holocene distribution patterns with that of their modern species ranges. The avifaunal remains from four sites were analysed by the authors and bird identifications from 10 additional sites were extracted from published reports. In the case of the Common Crane Grus grus, Grey Partridge Perdix perdix and Black Francolin Francolinus francolinus, shifts in distributions relate to significant changes in climate marking the transition from the Pleistocene to the Holocene. In contrast, the massive decline of the Griffon Vulture Gyps fulvus represents a more recent phenomenon related to anthropogenic impact on their habitats and food sources. For the Black‐bellied Sandgrouse Pterocles orientalis and the Pin‐tailed Sandgrouse P. alchata, changes in distributional range from the Early Holocene to the present could not be detected. Finally, a single bone of Macqueen's Bustard Chlamydotis macqueenii at Göbekli Tepe is unexpected and conceivably we are dealing with the remains of a rare vagrant, more likely to be found in dry steppe and desert habitats, which were located south of the study area at that time. This study highlights the value of archaeozoological finds in helping to understand how species distributional ranges have changed over time. Similarly, our work suggests that authors studying archaeozoological data should not assume that present‐day distributional ranges of taxa of interest represent the ranges of these species in the past.

Population decline of the Black-bellied Sandgrouse Pterocles orientalis in continental Spain, a main western Palearctic stronghold

Summary Many European farmland bird populations are rapidly declining because of agricultural intensification and land-use changes. Robust estimates of population sizes and trends, habitat use, and protected area coverage within the distribution range are crucial to inform the conservation and management of threatened species. Here we report on the results of the 2019 Black-bellied Sandgrouse Pterocles orientalis (BBS) survey promoted and coordinated by SEO/BirdLife to update its breeding distribution, population size, and trends in continental Spain. A total of 660 grid cells, 10 × 10 km, Universal Transverse Mercator (UTM), were surveyed (81% of the distribution area), with 2,257 visits to 1,750 walked transects (7,001 km in total; 10.6 km per UTM). BBS was detected in 43% of sampled UTMs. At transect level, occupancy was 11% higher inside protected areas. At UTM level, occupancy was estimated at 0.58 (Bayesian credible interval [BCI] 95%: 0.55–0.61), revealing that BBS occupied about half of its previous breeding range (2003–2005). Using hierarchical distance sampling modelling, we estimated an average density of 1.33 individuals/km2 in occupied areas, and a population of 4,025 individuals (confidence interval: 1,840–7,609) within sampled areas, with an additional 697 individuals (confidence interval 461–1,075) in areas that were not surveyed. Further, the relative abundance of BBS (Kilometric Abundance Index) declined by 63% between 2005 and 2019 (annual decline rate of 4.5%). BBS used agricultural habitats (73%) and unprotected areas (54%) despite a higher occupancy within protected areas. Given the recent decline rate and persistent threats, the BBS conservation status should be upgraded to “Endangered” in peninsular Spain. Its future depends on land-use changes and agricultural practices, in particular the maintenance of fallows, semi-natural habitats, and pastures for extensive grazing. Better protection of important areas and targeted conservation initiatives should be promoted to halt and reverse the population decline in this key western Palearctic stronghold.

GPS tracking reveals the timing of collisions with powerlines and fences of three threatened steppe bird species

Summary Collision with powerlines is a major cause of mortality for many bird species, including bustards and sandgrouse. In this work, we used GPS tracking data to identify the hour of collision of three threatened steppe birds, i.e. Little Bustard Tetrax tetrax, Black-bellied Sandgrouse Pterocles orientalis, and Pin-tailed Sandgrouse Pterocles alchata. Out of a data set of 160 GPS-tracked individuals collected over a 13-year period, we detected eight collision events with powerlines or fences. Of these, we were able to determine the timing of 87.5% of the collision events with a resolution accurate to within two hours. Our results reveal that collisions occurred throughout the year and at different hours of the day, presenting a challenge for implementing effective mitigation strategies. The use of dynamic and reflective or luminescent devices may therefore be appropriate to prevent collision of steppe birds with powerlines during the day and night. Overall, this study adds evidence to the utility of using tracking data to better understand anthropogenic mortality in birds.

Metabarcoding insights into the diet and trophic diversity of six declining farmland birds

Knowledge of feeding ecology of declining species, such as farmland birds, is essential to address their conservation requirements, especially when their habitats are suffering important reductions of trophic resources. In this study, we apply a metabarcoding approach to describe the diet composition of six of the most significant farmland birds inhabiting European cereal pseudo-steppes: little bustard, great bustard, pin-tailed sandgrouse, black-bellied sandgrouse, red-legged partridge, and common quail. We further studied seasonal diet variations (autumn to spring) in all species but the common quail, whose diet was studied during spring and summer. We show that study species´ diets mostly consisted of plants, although in the case of little bustard and great bustard arthropods are also highly relevant. Among arthropods, we found high proportions of thrips, arachnids, and springtails, which were previously unreported in their diet, and some taxa that could be used as antiparasitic food. Moreover, we report that little bustard’s diet is the least rich of that of all studied species, and that diet of all these species is less diverse in winter than in autumn and spring. Diet composition of these declining species supports the importance of natural and semi-natural vegetation and landscape mosaics that can provide a wide variety of arthropods, plants, and seeds all year-round.

Disentangling the drivers of Black-bellied Sandgrouse Pterocles orientalis nesting habitat use in a Mediterranean arid environment

ABSTRACTCapsule: Nest site selection of Black-bellied Sandgrouse Pterocles orientalis in an Algerian arid environment is dictated by a combination of topography, human presence, landscape and space.Aims: To disentangle the drivers affecting Black-bellied Sandgrouse nest habitat use in an Algerian arid environment.Methods: We used data on a series of topographic, anthropogenic, landscape and space variables, to identify the predictors of the occurrence probability of Black-bellied Sandgrouse nests. These variables were measured at nests (n = 33) and random points (n = 33) within landscape plots of 250 m radius.Results: The probability of a site being selected for nesting by Black-bellied Sandgrouse was negatively related to distance to the nearest cereal crops, but positively associated with the cover of natural water, cover of rocks, and distance to the nearest road. This probability was also high at elevations between 251 and 289 m.Conclusion: From a practical perspective, it would be interesting to reproduce the same investigation in other Mediterranean arid environments to find out if this species follows a similar pattern of nesting habitat use. This would provide guidance for future conservation actions and inform appropriate habitat management for this species.

Plumage development and moult in captive Black-bellied Sandgrouse Pterocles orientalis: age and sex variations

The sandgrouse, family Pteroclididae, are a group of birds adapted to open, arid habitats and powerful fliers but information on their plumage development and moult is scarce. In this study, the annual cycle of body plumage development, sequence and duration of primary flight feathers moult were investigated in Black-bellied Sandgrouse Pterocles orientalis, from hatching to the adult stage. Body plumage differed among juvenile, immature and subadult birds before their first breeding season. Yearling Black-bellied Sandgrouse showed three annual moults with only the pre-breeding one being complete. Juvenal body plumage was acquired shortly before the first attempts to fly at 5–6 weeks of age. The acquisition of definitive adult body plumage took place after the breeding season in late August, when birds were about 10–12 months old. The species typically replaced all primaries annually with a gradual descendent moult at a slow rate, taking 10–11 months for their completion, from December to September, including the breeding period. This study provides the first detailed analysis of flight feather development and moulting in the Black-bellied Sandgrouse, which provides useful ageing criteria based on the patterns of both primary growth and moult.

When do yearling male Black-bellied Sandgrouse Pterocles orientalis reach sexual maturation?

In the present study, a histological and morphometric investigation of testes in yearling male Black-bellied Sandgrouse Pterocles orientalis was performed during the reproductive period. The trial was conducted on four randomly selected yearling male birds that originated from eggs collected in the wild and artificially incubated. Upon sacrifice, testes were removed and routinely processed for light microscopic examination. Only two birds developed heavy testes, with enlarged tubular diameter of seminiferous tubules. A high correlation was observed between the mean paired testes weight and the total length, diameter of seminiferous tubules and relative seminiferous volume. Two birds presented tubules with a multilayered epithelium and germ cells developed until the stage of round spermatids and spermatozoa. The remaining two birds presented quiescent testes. In conclusion, the yearling males had apparently a relatively shorter breeding cycle and delayed sexual maturation than yearling females, which could explain the low fecundity rate observed in yearling birds of this species in captivity.

A multi-scale approach for identifying conservation needs of two threatened sympatric steppe birds

Habitat selection is an inherently scale-sensitive process in which detected selection patterns frequently depend on the scale of analysis employed. We used a multi-scale modelling approach to identify how the distributions of two sympatric birds are shaped by differential selection at the landscape, land use and microhabitat scales and by human infrastructures as possible sources of disturbance. We studied two threatened steppe birds, the pin-tailed sandgrouse (PTS) and black-bellied sandgrouse (BBS) in central Spain. Land use gradients explained most of the variation in PTS and BBS occurrence, but there was cross-scale interdependence between the lower (microhabitat) and upper (landscape) spatial scales for the PTS. Synergies between the three scales highlighted the importance of integrating habitat scales in a single modelling framework. The process of habitat selection was also modulated by human disturbance. Both species selected ploughs of large size distant from houses, tracks and other infrastructures, although BBS exhibited broader habitat tolerance than the PTS, and was more sensitive to human disturbance. At microhabitat scale, PTS selected ploughs with greater green vegetation cover and insect abundance and fallows with lower dry vegetation cover and height but greater stone cover. This might reflect a trade-off between camouflage (vegetation and stone cover for concealment) and visibility for predator detection and escape. Ploughs and fallows should be maintained by means of traditional 2-year rotations and low management during the breeding season. Ongoing urbanization trends and infrastructure development inside protected areas should be limited. Multi-scale models were key to identify scale-specific factors that determine sandgrouse habitat preferences and conservation requirements at appropriate levels, and are recommended to better guide regional and local conservation efforts of threatened species.

Growth Patterns and Developmental Strategy in the Black-Bellied SandgrousePterocles orientalis

As a result of convergent evolution, sandgrouse share similarities with some other precocial landbirds, namely Galliformes and precocial waders (Charadriiformes). They are birds of arid lands and hence their chicks face problems of predation risk and shortage of food and water, exacerbated by the patchy and unpredictable distribution of these resources. We therefore hypothesised that sandgrouse would be more precocious at hatching than precocial galliformes and charadriiformes living in more favourable habitats. Patterns of growth for body mass, wing, leg and sternum were described for the black-bellied sandgrouse Pterocles orientalis by a logistic model. Post-hatching development was characterised by the ratio of exponential growth rate (EGR) to relative size (Ln(W/A)) (W: Weight and A: Asymptotic size) at a given age. Developmental trajectories, indicating the degree of the development of precocity, were derived from these relationships as the slopes of least square regression of EGR on relative size. We also characterised the post-hatching development of body size in terms of maturation time. Growth parameters were compared to those of the Galliformes and precocial Charadriiformes using interspecific allometric relationships. Black-bellied sandgrouse hatched with relatively well developed body mass and legs, which accords with their faster post-hatching maturation. The development of body mass and wing reached their asymptotic sizes on steeper developmental trajectories than did the leg. The mean growth rate constant for the wing was the highest compared to those of the sternum and leg which were similar. In contrast to the leg, wing and sternum showed biphasic growth patterns. The black-bellied sandgrouse shows growth rates and a maturation degree at hatching that are intermediate between their convergent Galliformes and precocial Charadriiformes. It exhibits a developmental strategy in which both precocial legs and wings allow early development of either walking or flying. This constitutes an adaptive strategy to arid environments with low and unpredictable resource availability and high predation risk.

Middle Pleistocene vertebrate fossils from the Nefud Desert, Saudi Arabia: Implications for biogeography and palaeoecology

The current paucity of Pleistocene vertebrate records from the Arabian Peninsula – a landmass of over 3 million km2 – is a significant gap in our knowledge of the Quaternary. Such data are critical lines of contextual evidence for considering animal and hominin dispersals between Africa and Eurasia generally, and hominin palaeoecology in the Pleistocene landscapes of the Arabian interior specifically. Here, we describe an important contribution to the record and report stratigraphically-constrained fossils of mammals, birds and reptiles from recent excavations at Ti’s al Ghadah in the southwestern Nefud Desert. Combined U-series and ESR analyses of Oryx sp. teeth indicate that the assemblage is Middle Pleistocene in age and dates to ca. 500 ka. The identified fauna is a biogeographical admixture that consists of likely endemics and taxa of African and Eurasian affinity and includes extinct and extant (or related Pleistocene forms of) mammals (Palaeoloxodon cf. recki, Panthera cf. gombaszogenis, Equus hemionus, cf. Crocuta crocuta, Vulpes sp., Canis anthus, Oryx sp.), the first Pleistocene records of birds from the Arabian Peninsula (Struthio sp., Neophron percnopterus, Milvus cf. migrans, Tachybaptus sp. Anas sp., Pterocles orientalis, Motacilla cf. alba) and reptiles (Varanidae/Uromastyx sp.). We infer that the assemblage reflects mortality in populations of herbivorous animals and their predators and scavengers that were attracted to freshwater and plant resources in the inter-dune basin. At present, there is no evidence to suggest hominin agency in the accumulation of the bone assemblages. The inferred ecological characteristics of the taxa recovered indicate the presence, at least periodically, of substantial water-bodies and open grassland habitats.

Assessing the short‐term effects of capture, handling and tagging of sandgrouse

Capturing and marking free‐living birds permits the study of important aspects of their biology but may have undesirable effects. Bird welfare should be a primary concern, so it is necessary to evaluate and minimize any adverse effects of procedures used. We assess short‐term effects associated with the capture, handling and tagging with backpack‐mounted transmitters of Pin‐tailed Pterocles alchata and Black‐bellied Pterocles orientalis Sandgrouse, steppe birds of conservation concern. There was a significantly higher mortality (15%) during the first week after capture than during the following weeks (< 2.5%) in Pin‐tailed Sandgrouse, but no significant temporal mortality pattern in Black‐bellied Sandgrouse. In Pin‐tailed Sandgrouse, mortality rate during the first week increased with increasing relative transmitter and harness weight regardless of season, and with increasing handling time during the breeding season. There were no significant differences in mortality rate between study areas, type of tag, sex or age or an effect of restraint time. These results suggest the use of lighter transmitters (< 3% of the bird's weight) and a reduction of handling time (< 20 min), particularly during the breeding season, as essential improvements in procedure to reduce the mortality risk associated with the capture, handling and tagging of these vulnerable species.

Niche-habitat mechanisms and biotic interactions explain the coexistence and abundance of congeneric sandgrouse species.

Ascertaining which niche processes allow coexistence between closely related species is of special interest in ecology. We quantified variations in the environmental niches and densities of two congeneric species, the pin-tailed and the black-bellied sandgrouse (Pterocles alchata and Pterocles orientalis) in allopatry and sympatry under similar abiotic, habitat and dispersal contexts to understand their coexistence. Using principal component analysis, we defined environmental gradients (niche dimensions) including abiotic, habitat and anthropogenic variables, and calculated niche breadth, position and overlap of both species in sympatry and allopatry. Additionally, sandgrouse density was modelled as a function of the niche dimensions and the density of the other species. We found evidence that each species occupies distinct environmental niches in sympatry and in allopatry. The black-bellied sandgrouse exploits a broader range of environmental conditions (wider niche breadth) while the pin-tailed sandgrouse reaches high densities where conditions seem to match its optimum. In sympatry, both species shift their niches to intermediate positions, indicating the importance of abiotic factors in setting coexistence areas. Environmental conditions determine regional densities of pin-tailed sandgrouse whereas biotic interactions explain the density of the black-bellied sandgrouse in areas with abiotic conditions similarly conducive for both species. Highly suitable areas for the pin-tailed sandgrouse fall beyond the upper thermal limit of the black-bellied sandgrouse, leading to niche segregation and low densities for the latter. Finally, local niche shift and expansion plus possible heterospecific aggregation allow the pin-tailed sandgrouse to thrive in a priori less favourable environments. This work provides insight into how different mechanisms allow species coexistence and how species densities vary in sympatry compared to allopatry as a result of environmental filtering and biotic interactions.

Habitat preferences of sympatric sandgrouse during the breeding season in Spain: a multi-scale approach

Predictive species’ distribution models may answer ecological questions about habitat selection, co-occurrence of species and competition between them. We studied the habitat preferences and segregation of two sympatric species of declining sandgrouse, the black-bellied sandgrouse (Pterocles orientalis) and the pin-tailed sandgrouse (Pterocles alchata), during the breeding season. We developed predictive models that related sandgrouse presence to environmental variables at three different spatial levels: large geographical, landscape and microhabitat scales. At the large geographical scale, differences between sandgrouse distributions, in the Iberian Peninsula, seem to be explained mainly in terms of bioclimatology: pin-tailed sandgrouse appear to be a more thermophilous species and occupy warmer sites usually located in flatter areas. At the landscape spatial level, in those areas that exhibit environmental conditions allowing for both species’ co-existence at a large geographical scale, black-bellied sandgrouse appear to be more tolerant to environmental variation than pin-tailed sandgrouse. At the microhabitat level, however, differences between species could be related to different flocking behaviour as a consequence of different sensitivities to vegetation structure and predators. Thus, the observed spatial distribution patterns are the result of different ecological factors that operate at different spatial levels. Conservation guidelines for these species should therefore consider their habitat preferences at large geographical, landscape and microhabitat scales.

The Role of Birds in the Settlement of Shahr‐i Sokhta (Sistan, Iran) During the 3rd Millennium BC

ABSTRACTArchaeological excavations at the site of Shahr‐i Sokhta yielded many bird remains. The excellent state of preservation allowed for the identification of 2875 specimens attributed to 43 different species. The avifaunal assemblage is mainly characterized by aquatic species, such as the Eurasian coot (Fulica atra), representing 60% of the identified remains, and the Anseriformes. The presence of cinereous vulture (Aegypius monachus), see‐see partridge (Ammoperdix griseogularis), black‐bellied sandgrouse (Pterocles orientalis) and spotted sandgrouse (Pterocles senegallus) suggests that near the urban center there were also some very arid and semi‐desert areas. The bird remains of Shahr‐i Sokhta confirm the existence of environmental and climatic conditions that can still be found in central and northern Iran, near the Caspian Sea. With the exception of the Suliformes, Pelecaniformes and Accipitriformes, there is evidence that most species were hunted for their meat. Furthermore, eggshell fragments found at the site suggest that eggs were collected and used as food. Taphonomic analysis showed that the Gruiformes and the Anseriformes were eaten, while the other species were exploited for non‐food purposes. The use of bird bones as raw material is indicated by the presence of anthropic marks on the ulnae of large birds. Copyright © 2014 John Wiley & Sons, Ltd.

A temperature-based monitoring of nest attendance patterns and disturbance effects during incubation by ground-nesting sandgrouse

Sandgrouse are birds of arid environments adapted to cope with extreme temperature variations. We used temperature data-loggers to remotely study incubation rhythms by pin-tailed and black-bellied sandgrouse in Spain. In both species, mates switched incubation roles twice a day, between 08:00 and 10:00 and between 19:30 and 21:30, when the nest and ambient temperature were most similar. During mate switches, sandgrouse preferred to risk a cooling rather than a warming of eggs. In the pin-tailed sandgrouse, the timing of morning switches was consistent within-pairs, while the timing of evening switches was more related to sunset time. Absences lasted longer following a disturbance than during a mate switch. During disturbances, changes in nest temperatures depended on the changes in outside temperature, and negatively correlated with absence duration. Absences following a disturbance were shorter when the outside temperature was higher. Nesting success was low (19%), with no noticeable effect of data-loggers. Our study highlights some of the constraints that birds breeding in arid environments, such as sandgrouse, face during incubation. It also stresses out the importance of evaluating the consequences of disturbances during incubation, in particular nest visits. Temperature data-loggers can provide an easy and effective way of monitoring nests, without the need of repeated nest visits.

Wild‐laid versus captive‐laid eggs in the black‐bellied sandgrouse: Is there any effect on chick productivity?

Because survival in captivity is a significant determinant of birds available for release and reinforcement of wild populations, we aimed to identify sources of variation in mortality to assess potential impacts of management on chick productivity. We analyzed characteristics of Black-bellied Sandgrouse eggs collected from the wild and produced by captive pairs. Wild laid-eggs and pulled captive-laid eggs were incubated artificially and all chicks were hand-reared until seven weeks of age. Wild-laid eggs were significantly bigger, heavier, and denser than captive-laid eggs which showed a higher variability in size. Fertility, embryo mortality, and fertile egg hatchability were similar for wild-laid and captive-laid eggs (67.92% vs. 68%; 15.62% vs. 15.7%, and 80.55% vs. 84.44%, respectively). There were significant positive relationships between egg weigh/volume and chick hatch weight. Mortality of chicks hatched from wild-laid eggs was much lower than that of chicks from captive-laid eggs (19.44% vs. 60.5%) during the first week after hatching, but decreased and being nil from the third week. Heavier hatchlings from captive-laid eggs exhibited higher survival rates which is not the case of hatchlings from wild-laid eggs. These latter hatchlings had higher survival rates increasing with the age of eggs in relation with the period of natural incubation. The recommended age at which wild-laid eggs could be collected is at least 13 days for full chick survivability. We concluded that in our experimental captive breeding program of the Black-bellied Sandgrouse, productivity of viable hatchlings was much better from wild-laid eggs and as later as these were collected.

Habitat selection and partitioning of the Black-bellied Sandgrouse (Pterocles orientalis), the Stone Curlew (Burhinus oedicnemus) and the Cream-coloured Courser (Cursorius cursor) in arid areas of North Africa

Niche theory predicts that coexisting species with similar trophic requirements should demonstrate resource partitioning, particularly where resources are scarce. Conversely, this is not expected between species that do not share primary resources. This study analyses the patterns of spatial coexistence and habitat selection, on two spatial scales, of three species of semidesert regions in Morocco: the Black-bellied Sandgrouse (Pterocles orientalis), the Stone Curlew (Burhinus oedicnemus) and the Cream-coloured Courser (Cursorius cursor). Co-occurrence analysis results point to between-species segregation on a macrohabitat scale. Hotelling's T test of the species-presence data showed a pattern of macrohabitat selection that diverged from habitat availability for the three species with differences among them. Both the classification tree and the pattern of microhabitat selection obtained by model averaging showed scant overlap between the Sandgrouse and the Courser, suggesting habitat partitioning between them on a fine scale. Our results confirm spatial segregation of the three species, especially between species with different trophic strategies: the Sandgrouse versus the Stone Curlew and the Courser. The latter two species were best segregated on a microhabitat scale, supporting the conclusions that macro- and microhabitat selection are major factors in bird community configuration in arid ecosystems and contributing to reduce potential competition.

Drinking schedule of four sandgrouse species (Pterocles spp.) in relation to sunrise and season

Sandgrouse (Pterocles spp.) are adapted to extreme desert environments. One such adaptation is that males transport water in their abdominal feathers to water the nesting female and hatchlings. Hence, understanding sandgrouse drinking regime and regularly used water holes is of great conservation importance. We studied the arrival of four sandgrouse species at a single water hole in the western Negev Desert, Israel. During our visits, the most numerous species was the Spotted Sandgrouse, and in decreasing abundance, we found Black-bellied Sandgrouse, Crowned Sandgrouse, and Pin-tailed Sandgrouse. Black- bellied Sandgrouse arrived significantly earlier than Spotted Sandgrouse and Crowned Sandgrouse. Spotted Sandgrouse arrival peaked later in the morning than Black-bellied Sandgrouse and Crowned Sandgrouse. The data suggest that this is connected to the absolute number of birds for each of the species which influences their synchronous arrival. Also, we find that the amount of time a species spends at the water hole is influenced by the number of birds present, i.e., the species that stay the longest are also the most numerous. The mean temperature when Spotted Sandgrouse peaked was marginally higher (21.2°C) than recorded for Black-bellied (19.5°C) and Crowned Sand- grouse (19.3°C).

An improved night-lighting technique for the selective capture of sandgrouse and other steppe birds

The night-lighting technique is routinely used to catch birds. We improved this technique using a thermal infrared camera to catch steppe birds such as the sandgrouse. Target birds were located by an observer using the thermal camera, and approached and dazzled by another observer carrying a spotlight attached to a helmet and a hand-held net together with a playback noise to camouflage the footsteps of the observer. Using this improved technique, we caught on average 1.14 individuals per 3-h capture session (N = 81) and a total of 92 sandgrouse in 2007–2010 (86 pin-tailed sandgrouse Pterocles alchata and six black-bellied sandgrouse Pterocles orientalis). Capture rate and success were negatively influenced by moonlight (lowest during full moon nights). Our night-lighting technique is a highly selective and harmless method to capture sandgrouse and can be used for other small/medium-sized open-land birds or mammals.