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Mohammed Y. Shobrak 《Saudi Journal of Biological Sciences》2015,22(4):491-502
The numbers of Falco cherrug and Falco peregrinus trapped during their migration over the Kingdom of Saudi Arabia (KSA) were investigated from published reports and through interviews with well-known trappers and dealers over several years (1989–2013). The number of trapped individuals increased for both species over a 23 year period, which is probably related to an enhanced trapping effort. Time series analysis suggests that the number of Saker Falcons being trapped is likely to be stable with annual fluctuations in the coming ten-year period, whereas the number of trapped Peregrine Falcons will probably decline with a small fluctuation initially. Using the population viability analysis suggests a high extinction rate for the Saker Falcon population migrating through KSA during the coming 10 and 20 years; whereas Peregrine Falcons probably take more than 100 years to reach the extinction threshold. However, the increase in the trapping period, especially in the spring, that has been observed during the last five years could increase the number of falcons trapped in the future. As both falcon species are migratory, implementing conservation actions across all range states is important to ensure a favourable conservation status for the Saker and Peregrine Falcons. Both species will benefit through the implementation of the Global Action Plan (GAP), developed by the Saker Falcon Task Force. 相似文献
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Andrew Jenkins 《Ostrich》2013,84(3-4):416-424
Jenkins, A.R. 2000. Choracteristics of Peregrine and Lanner Falcon nesting habitots in South Africa. Ostrich 71 (3&4): 416-424. Peregrine Falcon, Falco peregrinus, and Lanner Falcon, F. biarmicus, nesting habitats in South Africa are described in terms of nest ledge, nest cliff and scree slope parameters, ond the environmental context of each site. Data were collected in a tropical study area where Peregrines and Lannen occurred in sympatry, from an allopatric south temperate Peregrine population, and opportunistically for bath species from other sites throughout the country. Elevation, ledge size, cliff size ond vegetation structure accounted for about 80%of the variation in falcon nesting habitots between species and between populations within species. Peregrines used larger nest ledges on higher, more elevated cliffs than Lanners, overlooking mare open, structurally complex Vegetation. Temperate Peregrines used smaller ledges on lower cliffs, overlooking vegetation that provided less refuge for overflying prey than subtropical pairs. Temperote Peregrines selected nest sites to minimize the negative effects of spring roinfall. Tropical Peregrines may have selected sites to maximize hunting and provisioning efficiency. 相似文献
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The saker (Falco cherrug) is a traditional and valued bird of Arabic falconry. Harvesting birds from the wild raises questions of its conservation status and sustainability. The external morphology of this species is highly variable and the Arabic system of classification identifies over 11 saker types, some of which are more favoured among Arab falconers than others. Our study assessed morphological variation of birds chosen for known natal origin. Although most variation was between individuals-within-regions, the remaining variation in size and plumage characters may be appropriately described as a gradual cline between small dorsally uniform brown sakers from western lowland regions (e.g. lowland Kazakstan, and south-west Russia) to large, dorsally barred russet, dark brown and grey coloured sakers from eastern highland regions (e.g. south-east Russia, Mongolia, and China). Between these extremes exists a plethora of highly variable and contiguous populations. Although preferred falconry types may originate from any of these populations, the preferred jarudi and 'sinjari sakers from northeastern Altai, Tuva, and Sayan populations, and the large sakers from eastern populations may be over exploited through trapping. The demand for wild sakers, however, may be substituted by an increasing number of captive bred falcons used for Arab falconry. 相似文献
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J. B. Mihoub N. G. Mouawad P. Pilard F. Jiguet M. Low C. Teplitsky 《Journal of avian biology》2012,43(5):472-480
Adjusting breeding phenology to climate fluctuations can be problematic for migratory birds as they have to account for local environmental conditions on the breeding grounds while migrating from remote wintering areas. Predicting general responses to climate change is not straightforward, because these responses vary between migrant species due to the species‐specific ecological drivers of breeding behaviour. Therefore more information is needed on species with different ecological requirements, including data on heritability of migration, factors driving phenological changes and how climate affects selection pressures. Here, we measure heritability in settlement dates and the effect of local climate at the breeding grounds on settlement dates, reproductive success and selection patterns in a French population of a trans‐Saharan migratory insectivorous raptor, the lesser kestrel Falco naumanni, monitored and ringed since 1996. Heritability of settlement dates was low (0.07 ± 0.03), indicating a weak evolutionary potential. Nevertheless, plasticity in settlement dates in response to temperatures allowed earlier settlement when early spring was warmer than average. Reproductive success and selection patterns were strongly affected by temperature during settlement and chick rearing respectively. Warmer spring decreased selection for earlier settling and warmer early summer increased reproductive success. Interestingly, selection for earlier settling was more intense in cooler springs, contrasting with patterns from passerines lagging behind food peaks. Altogether, these results suggest a positive effect of warmer temperatures on breeding performances of lesser kestrels most likely because the French population is at the coolest boundary of the species European breeding range. 相似文献
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F. Nittinger E. Haring W. Pinsker M. Wink A. Gamauf 《Journal of Zoological Systematics and Evolutionary Research》2005,43(4):321-331
The phylogeographic history of the lanner falcon ( Falco biarmicus ) and the phylogenetic relationships among hierofalcons ( F. biarmicus , Falco cherrug , Falco jugger and Falco rusticolus ) were investigated using mitochondrial (mt) DNA sequences. Of the two non-coding mt sections tested, the control region (CR) appeared more suitable as phylogenetic marker sequence compared with the pseudo control region (ΨCR). For the comprehensive analysis samples from a broad geographic range representing all four hierofalcon species and their currently recognized subspecies were included. Moreover, samples of Falco mexicanus were analysed to elucidate its phylogenetic relationships to the hierofalcons. The sequence data indicate that this species is more closely related to Falco peregrinus than to the hierofalcons. In the DNA-based trees and in the maximum parsimony network all hierofalcons appear closely related and none of the species represents a monophyletic group. The close relationships among haplotypes suggest that the hierofalcon complex is an assemblage of morphospecies not yet differentiated in the genetic markers used in the present study and that the radiation of the four hierofalcon species took place rather recently. Based on the high intraspecific diversity found within F. biarmicus we assume an African origin of the hierofalcon complex. The observed pattern of haplotype distribution in the extant species may be due to incomplete lineage sorting of ancestral polymorphisms, and interspecific gene flow through hybridization. 相似文献
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Pascual López-López José Verdejo Emilio Barba 《European Journal of Wildlife Research》2009,55(2):125-132
In this paper, we describe and analyze the diet of peregrine falcons during a long-term period (1982–2002). A combination of direct observations of prey brought to nests, prey remains, and regurgitated pellets were used to calculate diet diversity and dietary overlap between peregrine pairs. We also examined diet diversity in relation to breeding performance. All peregrine pairs fed mainly on birds, with pigeons the most common prey. An increase in pigeon availability has been associated with both an increase in population size and an increase in breeding performance (measured as the average productivity of pairs per year) of a small peregrine falcon population in eastern Spain. Average productivity was lower when dietary breadth was higher. We speculate that our results were the synergistic effect of declining persecution and increased pigeon availability through increased popularity of keeping racing pigeons. There is a conflict of interests between pigeon fanciers and peregrine conservation. As a consequence, this could result to an increased risk of mortality by direct persecution. In accordance with this, conservation measures aimed at preventing direct persecution are encouraged. 相似文献
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Mace GM Collen B Fuller RA Boakes EH 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2010,365(1558):3743-3751
Continuing downward trends in the population sizes of many species, in the conservation status of threatened species, and in the quality, extent and connectedness of habitats are of increasing concern. Identifying the attributes of declining populations will help predict how biodiversity will be impacted and guide conservation actions. However, the drivers of biodiversity declines have changed over time and average trends in abundance or distributional change hide significant variation among species. While some populations are declining rapidly, the majority remain relatively stable and others are increasing. Here we dissect out some of the changing drivers of population and geographic range change, and identify biological and geographical correlates of winners and losers in two large datasets covering local population sizes of vertebrates since 1970 and the distributions of Galliform birds over the last two centuries. We find weak evidence for ecological and biological traits being predictors of local decline in range or abundance, but stronger evidence for the role of local anthropogenic threats and environmental change. An improved understanding of the dynamics of threat processes and how they may affect different species will help to guide better conservation planning in a continuously changing world. 相似文献
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Andrew Jenkins 《Ostrich》2013,84(3-4):385-392
Jenkins, A.R. 2000. Factors affecting breeding success of Peregrine and Lonner Falcons in South Africa. Ostrich 71 (384): 385-392. Breeding success was recorded for three Peregrine Falcon, Falco peregrinus, populations in South Africa over nine years, and for Peregrine and Lanner Falcon, Ebiarmicus, populations in an area of sympatry over three years. The objectives of the study were to measure geographic and interspecific variation in reproductive performance, and determine environmental correlates of productivity. Territory occupancy, the frequency of breeding per occupied territory and clutch size did not vary significantly between the three Peregrine populations. However, Peregrine breeding success was generally lower on the Cape Peninsula (1. 11 young fledged per territorial poir), higher in the Soutpansberg (1.36) and highest on the Orange River (1.70). Overall, fledging rates of Soutpansberg Peregrines and Lanners were not significantly different, although annual productivity of the Lonner population was consistently higher. Neither species' breeding success was significantly depressed by the presence of close neighbouring pairs of the other, suggesting that they were not active competitors. Breeding performance of Peregrines on the Cape Peninsula correlated strongly with spring weather conditions: egg and hatchling survival was lower in wet years, and fledging rates were higher in warm years. Annual productivity of Orange River Peregrines correlated positively with the height of the river at the onset of breeding, and productivity of Soutpansberg Peregrines was higher in seasons following years of high rainfall. Elements of the physical structure of the nesting habitat (exposure of the nest ledge, height of the nest cliff) correlated positively with Peregrine breeding performance. Breeding success of Soutpansberg Lanners was largely unaffected by any of the environmental variables considered. Overall, it is proposed that Peregrine productivity reflected variation in the physical environment and its affect on prey availability. 相似文献
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THOMAS ALERSTAM 《Ibis》1987,129(S1):267-273
Measurements in 10-s intervals by a tracking radar showed average speeds of about 25 ms-1 for a Peregrine Falcon Falco peregrinus and a Goshawk Accipiter gentilis during four stoops lasting 40–110 s, with angles of dive between 13o and 64o , and involving height losses between 450 and 1080 m. Maximum speeds during 10-s intervals were between 31 and 39 ms-1 in the Peregrine Falcon, and close to 30 ms-1 in the Goshawk. The observed speeds are well below the maximum possible terminal speeds in steep or vertical dives according to theoretical estimation. By adopting a moderate stooping speed, raptors may gain in hunting precision. 相似文献
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Okello JB Masembe C Rasmussen HB Wittemyer G Omondi P Kahindi O Muwanika VB Arctander P Douglas-Hamilton I Nyakaana S Siegismund HR 《The Journal of heredity》2008,99(5):443-452
We investigated population genetic structure and regional differentiation among African savannah elephants in Kenya using mitochondrial and microsatellite markers. We observed mitochondrial DNA (mtDNA) nucleotide diversity of 1.68% and microsatellite variation in terms of average number of alleles, expected and observed heterozygosities in the total study population of 10.20, 0.75, and 0.69, respectively. Hierarchical analysis of molecular variance of mtDNA variation revealed significant differentiation among the 3 geographical regions studied (F(CT) = 0.264; P < 0.05) and a relatively lower differentiation among populations within regions (F(SC) = 0.218; P < 0.0001). Microsatellite variation significantly differentiated among populations within regions (F(SC) = 0.019; P < 0.0001) but not at the regional levels (F(CT) = 0.000; P > 0.500). We attribute the high differentiation at the mitochondrial genome to the matrilineal social structure of elephant populations, female natal philopatry, and probably ancient vicariance. Lack of significant regional differentiation at the nuclear loci vis-a-vis strong differences at mtDNA loci between regions is likely the effect of subsequent homogenization through male-mediated gene flow. Our results depicting 3 broad regional mtDNA groups and the observed population genetic differentiation as well as connectivity patterns should be incorporated in the planning of future management activities such as translocations. 相似文献
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Italo Barrai Gino Schiliro Maria Beretta Paola Mazzetti Antonio Russo Giovanna Russo Mancuso 《Human genetics》1987,75(1):1-3
Summary The population structure of two alleles with similar characteristics, HbS and beta-thalassemia, was studied in the same area in Sicily. It was observed that beta-thalassemia has uniform frequencies over the island, and that HbS shows a South-North cline. A singularity exists for HbS in the town of Butera, where the frequency of the S gene is six times higher than the island average. It was suggested that HbS entered Sicily from Greece (or directly from North Africa) when the beta-thalassemia allele was already established in the Island. 相似文献
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Each year salmon and other fishes are caught and used for supportive breeding programs that attempt to augment natural populations
that are threatened with extinction. These programs typically mate individuals randomly and as such they overlook the importance
of genetic quality to offspring fitness and ultimately to ensuring population health. Here, we use Chinook salmon (Oncorhynchus tshawytscha) and a fully crossed quantitative genetic breeding design to partition genetic variance in offspring performance (growth
and survival) to additive and non-additive genetic effects as well as maternal effects. We show that these three effects contribute
about equally to the variation in survival, but only non-additive genetic and maternal effects contribute to variation in
growth. Some of the genetic effects could be assigned to variation at the class IIB locus of the major histocompatibility
complex, but the maternal effects were not associated with egg size and we found no relationship between dam phenotypic measures
and offspring survival or growth. We also found no relationship between sire sexually selected characters and offspring survival
or growth, which is inconsistent with a “good genes” hypothesis. Finally, we show that incorporation of genetic quality into
supportive breeding programs can increase offspring growth or survival by between 3% and 19% during the endogenous feeding
stage alone, and projections to adulthood suggest that survivorship could be over four fold higher.
Electronic Supplementary Material Supplementary material is available in the online version of this article at and is accessible for authorised users. 相似文献
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S. J. PARR 《Ibis》1985,127(1):60-73
Brecding densities, nest spacing, breeding habitat, productivity and diet are compared for Hobbies Falco subbuteo in the New Forest (heathland and largely coniferous woodland), river valley farmland and largely cultivated chalk downland. Regular spacing of nests was characteristic of the three areas. The New Forest had the highest density and lowest mean nearest neighbour distance for nests. Nest areas tended to be traditional. A high proportion of clutches were laid in disused nests of Carrion Crows Corvus corone which favoured the crowns of Scots pine Pinus sylvestris. Except on downland, the availability of such sites is unlikely to provide a constraint on Hobby distribution. In the New Forest, woodland clearings and valley mires were a feature of nest territories. There was no evidence of a habitat-related difference in fledging success.
Division of labour between sexes is marked. The male is responsible for provisioning the female throughout most of the breeding season as well as the young. During the incubation period many woodland passerines were taken but when feeding nestlings Hobbies tended to specialize on Swallows Hirundo rustica , House Martins Delichon urbica and, where they had access to more urban areas, Swifts Apus apus. By breeding relatively late, Hobbies take advantage of the availability of the juveniles of such prey on which to feed their young. Large insects supplemented the diet before egg-laying and when the Hedged young were learning to hunt. 相似文献
Division of labour between sexes is marked. The male is responsible for provisioning the female throughout most of the breeding season as well as the young. During the incubation period many woodland passerines were taken but when feeding nestlings Hobbies tended to specialize on Swallows Hirundo rustica , House Martins Delichon urbica and, where they had access to more urban areas, Swifts Apus apus. By breeding relatively late, Hobbies take advantage of the availability of the juveniles of such prey on which to feed their young. Large insects supplemented the diet before egg-laying and when the Hedged young were learning to hunt. 相似文献
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Kathleen M. Fisch Jordana M. Henderson Ronald S. Burton Bernie May 《Conservation Genetics》2011,12(6):1421-1434
Over the last two decades, the collapse of the endangered delta smelt (Hypomesus transpacificus) in the San Francisco Bay-Delta has resulted in politically charged conservation decisions, including the rationing of valuable Delta water for use in California agriculture and urban centers. A fundamental question remaining in delta smelt conservation is whether current management strategies have been appropriately designed to protect the remaining genetic variation in delta smelt populations, rather than merely mitigating the decline of the species. We used 15 microsatellite markers to characterize genetic variation within and among sampling regions on geographic and temporal scales, to estimate changes in effective population size over time, to determine if a genetic bottleneck exists and to define conservation management units for this species. A genetic bottleneck was detected in each of the four sampling years, and a significant decline in effective population size was observed between sampling years 2003 and 2007. We also detected a weak geographic signal in any given sampling year that was unsupported by temporal consistency of this signal. We assessed two strategies for defining conservation units, and concluded that continuing to manage the species as a single, panmictic population throughout its range is the most feasible management strategy. The results of this study will inform conservation decisions and provide an effective means for genetically monitoring this imperiled species. 相似文献