Emirates Center for Wildlife Propagation

Sperm competition is a powerful force driving the evolution of ejaculate and sperm traits. However, the outcome of sperm competition depends on many traits that extend beyond ejaculate quality. Here, we study male North African houbara bustards (Chlamydotis undulata undulata) competing for egg fertilization, after artificial insemination, with the aim to rank the importance of 14 parameters as drivers of siring success. Using a machine learning approach, we show that traits independent of male quality (i.e., insemination order, delay between insemination and egg laying) are the most important predictors of siring success. Traits describing intrinsic male quality (i.e., number of sperm in the ejaculate, mass motility index) are also positively associated with siring success, but their contribution to explaining the outcome of sperm competition is much lower than for insemination order. Overall, this analysis shows that males mating at the last position in the mating sequence have the best chance to win the competition for egg fertilization. This raises the question of the importance of female behavior as determinant of mating order.

Growing urbanization increasingly influences ecosystems worldwide. While the effects of urban conditions within species (through either plastic or evolutionary responses) have been widely studied, their potential influences among species (through environmental filter), especially concerning their colouration, remain poorly known. Here, we investigated whether avian communities breeding inside and outside a major European city (Paris) differ with regards to melanin‐based plumage colouration. Melanins are heritable pigments present in many taxa and have a series of unique properties that may allow coping with urban conditions. Using melanic‐based colouration as an integrative phenotypic marker, we predicted 1) that the probability of breeding inside the city should increase with the intensity of species melanin‐based colouration, 2) that for species breeding both inside and outside the city, density should increase with the intensity of dark colouration inside the city, but not outside the city and 3) that species not breeding inside the city should not exhibit this positive relation between density and colouration. Our results confirmed these predictions. In addition, the density of species not breeding inside the city decreased with the darkness of their plumage. Altogether, these results suggest that bird species experience a balance between costs and benefits of melanin‐based colouration shaped by environmental conditions. Both the environmental filtering and the urbanisation‐shaped relation between density and colouration evidenced here are likely a general trend, however possibly modulated by additional local environmental conditions. Their importance may even be underestimated given the restricted geographical scale and the overall urbanization rate of the region studied. Further studies involving regions with contrasted environmental conditions should gain insight into the consequences of urbanization worldwide on traits associated with melanin‐based colouration.

Piptatherum fumeauxii F.M. Vázquez, Chamboul. & C. Chatel. sp. nova (Poaceae) is described from the Hoggar Mountains in central Sahara, Algeria. It morphologically resembles P. coerulescens and P. holciforme var. longiglume, but differs from them by the narrow panicles, shorter spikelets and smaller floral parts. The presence of P. holciforme in Libya is confirmed, while it is excluded from the flora of Morocco. Lectotypes are designated for the names Milium coerulescens Desf. and P. holciforme subsp. longiglume Hausskn., and the latter is recognized as P. holciforme subsp. longiglume (Hausskn.) Freitag ex F.M. Vázquez & F. Márquez comb. et stat. nov.

Conservation breeding programs pursue the double objective of preserving genetic diversity and producing individuals to support in situ conservation measures. Genetic management and monitoring are commonly based on pedigree analyses and are therefore dependent on the pedigree quality and the underlying assumption that founders of the captive population are neither inbred nor related to each other or to the captive population. Should founders be related, this assumption may lead to an overestimation of genetic diversity and an underestimation of inbreeding in captivity. In this study, we examined the effects of the founder assumption on estimates of genetic diversity by combining three approaches: (1) computer simulations of pedigrees of theoretical captive populations and their associated in situ source populations, (2) analysis of pedigrees of real conservation breeding programs and (3) microsatellite‐based computation of kinship among founders from a captive population of houbara bustard. The theoretical approach revealed that the captive population's average mean kinship Mk increases linearly with founder average Mk. The bias in Mk due to the founder assumption was strongly related to the effective size of the source population and to pedigree quality while remaining critical after 25 generations of captivity. Results based on real populations were consistent with theoretical ones and confirmed the overestimation of genetic diversity in captive populations. Overall, our results indicate that under situations classically encountered in conservation breeding programs (e.g. small and isolated source population, incomplete pedigrees), estimates of genetic diversity are potentially highly overestimated, challenging the genetic management of captive populations of species of conservation concern.

The Irano-Turanian Rumex chalepensis has been recorded in two localities in Morocco since 2013, apparently for the first time in Africa and rather disjunct from the species' known distribution range. Populations were found in eastern Morocco: one close to the city of Midelt (High Moulouya valley), in the high plains between the Middle Atlas and High Atlas mountain ranges, whereas the second is located close to the city of Jerada (Lower Moulouya valley / High plateaus), close to the border with Algeria. This species is morphologically similar to R. obtusifolius and might have been overlooked elsewhere in North Africa. The presence of the latter in Morocco, always assumed to be very questionable up to present, is also confirmed here. Distinguishing features for these two species are discussed, some illustrations are also presented and R. chalepensis is lectotypified. It is most likely a naturalized weed in Morocco although it cannot be completely ruled out that it is a previously overlooked native species with two disjunct areas, an Irano-Turanian and North African one.

Although density-dependent processes and their impacts on population dynamics are key issues in ecology and conservation biology, empirical evidence of density-dependence remains scarce for species or populations with low densities, scattered distributions, and especially for managed populations where densities may vary as a result of extrinsic factors (such as harvesting or releases). Here, we explore the presence of density-dependent processes in a reinforced population of North African Houbara bustard (Chlamydotis undulata undulata). We investigated the relationship between reproductive success and local density, and the possible variation of this relationship according to habitat suitability using three independent datasets. Based on eight years of nests monitoring (more than 7,000 nests), we modelled the Daily Nest Survival Rate (DNSR) as a proxy of reproductive success. Our results indicate that DNSR was negatively impacted by local densities and that this relationship was approximately constant in space and time: (1) although DNSR strongly decreased over the breeding season, the negative relationship between DNSR and density remained constant over the breeding season; (2) this density-dependent relationship did not vary with the quality of the habitat associated with the nest location. Previous studies have shown that the demographic parameters and population dynamics of the reinforced North African Houbara bustard are strongly influenced by extrinsic environmental and management parameters. Our study further indicates the existence of density-dependent regulation in a low-density, managed population.

While uncovering the costs and benefits of polyandry has attracted considerable attention, assessing the net effect of sexual selection on population fitness requires the experimental manipulation of female mating over generations, which is usually only achievable in laboratory populations of arthropods. However, knowing if sexual selection improves or impairs the expression of life history traits is key for the management of captive populations of endangered species, which are mostly long‐lived birds and mammals. It might therefore be questionable to extrapolate the results gathered on laboratory populations of insects to infer the net effect of sexual selection on populations of endangered species. Here, we used a longitudinal dataset that has been collected on a long‐lived bird, the houbara bustard, kept in a conservation breeding program, to investigate the effect of enforced monoandry on female investment into reproduction. In captivity, female houbara bustards are artificially inseminated with sperm collected from a single male (enforced monoandry), or sequentially inseminated with semen of different males (polyandry), allowing post‐copulatory sexual selection to operate. We identified female lines that were produced either by monoandrous or polyandrous inseminations over three generations, and we compared reproductive investment of females from the two mating system groups. We found that females in the polyandrous lines had higher investment into reproduction as they laid more eggs per season and produced heavier hatchlings. Higher reproductive investment into reproduction in the polyandrous lines did not result from inherited differences from females initially included in the two mating system groups. These results show that removal of sexual selection can alter reproductive investment after only few generations, potentially hindering population fitness and the success of conservation breeding programs.

Population reinforcement, through translocations of individuals, aims to restore populations of threatened species. The increase in population size or geographic distribution is often used as positive facts when assessing the recovery of a species, making abundance monitoring a major criterion. Based on 8‐year monitoring of a reinforced population of North African Houbara bustard (Chlamydotis undulata undulata), over an area of 50 170 km² in the eastern region of Morocco, we assessed the success of management actions by assessing spatial and temporal variation in abundance as well as the factors driving this variation. We used count data to estimate and spatialize population abundance. We then assessed environmental (climate) and management covariates (release effort and hunting management) associated with temporal and spatial variation in abundance. The overall estimate of abundance in the study area was 16 918 individuals (95% CI = 13 629–21 027) over our study period, with strong variation between years (range = 10 409–32 401). Our results highlighted strong spatial heterogeneity over the study area, linked to spatial variation in local climate and management conditions. Local abundances were negatively associated with local temperature, were higher in hunting than in non‐hunting areas, and were positively influenced by the number of birds released around the focal point. In addition to describing the spatio‐temporal variation in the abundance of the species on a large scale, we estimated two major proxies of its conservation status: population size and population trend. The determination of these proxies and the comparison with the counterfactual state of the species confirms the beneficial impact of the restoration and protection program on the dynamics of the North African Houbara bustard, while underlining the dependence of these dynamics on ongoing management.

Although captive breeding programs are valuable for conservation, they have been shown to be associated with genetic changes, such as adaptation to captivity or inbreeding. In addition, reproductive performance is strongly age-dependent in most animal species. These mechanisms that potentially impact reproduction have often been studied separately, while their interactions have rarely been addressed. In this study, using a large dataset of nine male and female reproductive parameters measured for 12,295 captive houbara bustards (Chlamydotis undulata undulata) over 24 years, we investigated the relative and interactive effects of age, inbreeding and number of generations in captivity on reproduction. We clearly identified (1) senescence patterns in all parameters studied; (2) negative effects of inbreeding on sperm characteristics, display behavior, egg weight, egg volume and hatching probability; and (3) changes in phenotypic values for seven parameters according to number of generations in captivity. However, the effect sizes associated with age were substantially greater than those associated with inbreeding and number of generations in captivity. Beyond the independent effects of these three factors on reproductive parameters, the results highlighted their interactive effects and thus the importance of integrating them in the design of genetic management plans for conservation breeding programs.

Parental age has profound consequences for offspring's phenotype. However, whether patrilineal age affects offspring sperm production remains unknown, despite the importance of sperm production for male reproductive success in species facing post-copulatory sexual selection. Using a longitudinal dataset on ejaculate attributes of the houbara bustard, we showed that offspring sired by old fathers had different age-dependent trajectories of sperm production compared to offspring sired by young fathers. Specifically, they produced less sperm (-48%) in their first year of life, and 14% less during their lifetime. Paternal age had the strongest effect, with weak evidence for grandpaternal or great grandpaternal age effects. These results show that paternal age can affect offspring reproductive success by reducing sperm production, establishing an intergenerational link between ageing and sexual selection.

In many taxa, breeding success depends heavily on reliable vocal recognition between parents and offspring. Although the acoustic basis of this recognition has been explored in several species, few studies have examined the evolution of acoustic cues to identity across development. Here, in a captive breeding program, we investigated for the first time the acoustic signals produced by North African houbara bustard Chlamydotis undulata undulata chicks. Two call types (contact and distress) were recorded from 15 chicks in 4 age classes. Acoustic analyses showed that the acoustic parameters of the calls varied systematically with age in both contact and distress calls. However, both call types remained highly stereotyped and individualized between chicks at every tested age, indicating that calls encode reliable information about individual identity throughout development, thus potentially enabling the mother to distinguish her own chicks through their development up to fledging. Playback experiments are now needed to verify such parent-chick recognition in houbara bustards and its efficiency across chick ontogeny.

Protection and restoration of species in the wild may require conservation breeding programs under genetic management to minimize deleterious effects of genetic changes that occur in captivity, while preserving populations' genetic diversity and evolutionary resilience. Here, through interannual pedigree analyses, we first assessed the efficiency of a 21-year genetic management, including minimization of mean kinship, inbreeding avoidance, and regular addition of founders, of a conservation breeding program targeting on Houbara bustard (Chlamydotis undulata undulata) in Morocco. Secondly, we compared pedigree analyses, the classical way of assessing and managing genetic diversity in captivity, to molecular analyses based on seven microsatellites. Pedigree-based results indicated an efficient maintenance of the genetic diversity (99% of the initial genetic diversity retained) while molecular-based results indicated an increase in allelic richness and an increase in unbiased expected heterozygosity across time. The pedigree-based average inbreeding coefficient F remained low (between 0.0004 and 0.003 in 2017) while the proportion of highly inbred individuals (F > .1) decreased over time and reached 0.2% in 2017. Furthermore, pedigree-based F and molecular-based individual multilocus heterozygosity were weakly negatively correlated, (Pearson's r = -.061 when considering all genotyped individuals), suggesting that they cannot be considered as alternatives, but rather as complementary sources of information. These findings suggest that a strict genetic monitoring and management, based on both pedigree and molecular tools can help mitigate genetic changes and allow to preserve genetic diversity and evolutionary resilience in conservation breeding programs.

A new species of blister beetle (Coleoptera, Meloidae, Mylabrini), Croscherichia armass Ruiz, François & García-París, sp. nov. , is described from the arid steppes of eastern Morocco (Missour, Boulemane Province). The new species presents traits shared with both Croscherichia and desert species of the genus Ammabris , making it morphologically singular. Conspicuous external similarities (coloration pattern, shape of the mandibles, setation) between C. armasssp. nov. and Ammabris allow the two to be easily confused. However, C. armasssp. nov. can be readily distinguished from all other Croscherichia species by the following traits: reddish-orange legs with dark tarsi; relatively short black antennae with the proximal-most three to four antennomeres of each antenna having a reddish-brown coloration; dense and silvery body setation that lies over most of the body integument; straight and pointed outer mandible margins that protrude from the labrum; a mesosternum with an angulate anterior margin; a short, subcylindrical, and weakly spatulate external metatibial spur that is truncated obliquely at the apex. Croscherichia armasssp. nov. is only known from three localities in the arid Hammada steppes, which are located within the Quaternary alluvial plains of the Muluya river valley. Live specimens of C. armasssp. nov. were found in flight and actively feeding on Atriplex halimus (Chenopodiaceae) flowers at the end of summer (mid-September). The phenology of C. armasssp. nov. is exceptional as no other Mylabrini species known from eastern areas of Morocco are active in late summer.

Male senescence has detrimental effects on reproductive success and offspring fitness. When females mate with multiple males during the same reproductive bout, post-copulatory sexual selection that operates either through sperm competition or cryptic female choice might allow females to skew fertilization success towards young males and as such limit the fitness costs incurred when eggs are fertilized by senescing males. Here, we experimentally tested this hypothesis. We artificially inseminated female North African houbara bustards with sperm from dyads of males of different (young and old) or similar ages (either young or old). Then, we assessed whether siring success was biased towards young males and we measured several life-history traits of the progeny to evaluate the fitness costs due to advanced paternal age. In agreement with the prediction, we found that siring success was biased towards young males, and offspring sired by old males had impaired hatching success, growth and post-release survival (in females). Overall, our results support the hypothesis that post-copulatory sexual selection might represent an effective mechanism allowing females to avoid the fitness costs of fertilization by senescing partners.

Kinship and inbreeding are two major components involved in sexual selection and mating system evolution. However, the mechanisms underlying recognition and discrimination of genetically related or inbred individuals remain unclear. We investigated whether kinship and inbreeding information is related to low‐frequency vocalizations, “booms,” produced by males during their courtship in the lekking houbara bustard (Chlamydotis undulata undulata). Based on a captive breeding program where the pedigree of all males is known, we investigated the similarity of booms’ acoustic parameters among captive males more or less individually inbred and therefore genetically related with each other. In the wild, we investigated the relationship between the spatial distribution of males within leks and the similarity of acoustic parameters of their booms. In the captive population, we found (a) a relationship between the individual inbreeding level of captive males and their vocalization parameters; (b) that kin share similar frequency and temporal characteristics of their vocalizations. In the wild, we found no evidence for spatial structuring of males based on their acoustic parameters, in agreement with previous genetic findings on the absence of kin association within houbara bustard leks. Overall, our results indicate that genetic information potentially related to both the identity and quality of males is contained in their vocalizations. Kinship and inbreeding are two major components involved in sexual selection and mating system evolution. However, the mechanisms underlying recognition and discrimination of genetically related or inbred individuals remain unclear. Here, we investigated whether kinship and inbreeding information is related to low‐frequency vocalizations produced by males houbara bustard.

Ejaculate attributes are important factors driving the probability of fertilizing eggs. When females mate with several males, competition between sperm to fertilize eggs should accentuate selection on ejaculate attributes. We tested this hypothesis in the North African houbara bustard (Chlamydotis undulata undulata) by comparing the strength of selection acting on two ejaculate attributes when sperm from single males or sperm from different males were used for insemination. In agreement with the prediction, we found that selection on ejaculate attributes was stronger when sperm of different males competed for egg fertilization. These findings provide the first direct comparison of the strength of selection acting on ejaculate attributes under competitive and non-competitive fertilizations, confirming that sperm competition is a major selective force driving the evolution of ejaculate characteristics.

The success of translocation programmes is reflected by the ability of translocated individuals to survive and reproduce in their new environment. However, it has previously been reported that translocated individuals have lower demographic performance than their wild-born conspecifics, due to management and individual factors (such as release conditions or age). Here, we study six breeding parameters in free-ranging females of the North African Houbara bustard (Chlamydotis undulata undulata) and compare these parameters between captive-bred released (n = 204) and wild-born (n = 101) birds, considering the age of individuals and the period of release (autumn versus spring). Our results indicate that (1) captive-bred released females successfully breed in the wild; (2) for three out of the six breeding parameters studied, released females show lower performances than wild-born females; but, (3) Although we observed consistently reduced breeding performances in 1 year old females relative to older females, we did not uncover any interaction between age and the origin of females, suggesting that the impairment of breeding parameters in released females is long lasting; and, (4) interestingly, this impairment of breeding parameters depends on the period of release, with lower breeding performances for spring releases compared to autumn releases. Overall, our study highlights the capacity of captive-bred females to reproduce in the wild, contributing to the dynamics of the population beyond their individual history. Our results also uncover complex variations of breeding parameters in translocated birds, but suggest that these differences can be minimized through an appropriate translocation strategy.

Trox strandi is a rare species whose taxonomic status has been controversial and so far is only known from the type-locality, Sidi-bel-Abbes, in northwestern Algeria. However, it has been indicated generically from Libya, Tunisia and Morocco, but without providing precise locations or additional material. During surveys in southeastern Morocco in recent years, we have found two specimens ascribable to this species in as many other locations (Tameslemt, in the north foothills of the Eastern High Atlas, and Ksabi, in the upper basin of the Moulouya river), which are the first accurate records for this country. These stations are located in regions with arid and semi-arid bioclimate and scarce vegetation cover. Data on the habitat, diagnostic traits and morphological variability of the species are provided.

Offspring resulting from mating among close relatives can suffer from impaired fitness through the expression of recessive alleles with deleterious effects. Post‐copulatory sperm selection (a pre‐zygotic mechanism of cryptic female choice) has been suggested to be an effective way to avoid inbreeding. To investigate whether post‐copulatory female choice allows the avoidance of fertilization by close kin, we performed artificial inseminations in a promiscuous bird, the houbara bustard (Chlamydotis undulata undulata). Females were inseminated with a mix of sperm from triads of males, each constituted of a male genetically unrelated to the female, a first cousin, and a half‐sibling. When counting the number of eggs sired by unrelated males, cousins or half‐siblings, we found a significant deviation from the expected random distribution, with more eggs sired by unrelated males. However, offspring sired by cousins, and especially by half‐siblings suffered from high pre‐hatching mortality, suggesting that the observed paternity skew towards unrelated males might reflect differential offspring mortality rather than sperm selection. In agreement with this hypothesis, within‐triad siring success was similar for the three parental relatedness categories, but the relationship between siring and hatching success differed across categories. In clutches with high hatching success, unrelated males had the highest success while in clutches with high failure rate, half‐siblings had the highest success. Offspring sired by half‐siblings also suffered from reduced growth rate during the first three months and higher post‐hatching mortality. Hence, despite substantial fitness costs associated with fertilization by close relatives, females do not seem to select sperm of unrelated males. This article is protected by copyright. All rights reserved.