4,046 research outputs found
Molecular genetics of the northern bobwhite, scaled quail, and Gambel's quail
No full textThe New World quails (Odontophoridae) are a family of galliforms that includes nine extant genera and 32 species. Little is known about the biogeography of the family or about the evolutionary relationships among the New World quail genera and species. This study used mitochondrial DNA to examine 1) the phylogenetic relationships among the New World quail genera, and the phylogeography of the northern (Colinus virginianus), Yucatán (Colinus nigrogularis), and crested (Colinus cristatus) bobwhites, and the scaled quail (Callipepla squamata) and Gambel’s quail (Callipepla gambelii). Phylogenetic analyses revealed that Odontophoridae was composed of three distinct lineages that diverged from one another during the Miocene: a Dendrortyx group composed of the genera Colinus, Callipepla, Oreortyx, Philortyx, and Dendrortyx; an Odontophorus group of Odontophorus, Dactylortyx, and Cyrtonyx, and the tawny–faced quail (Rhynchortyx cinctus). The northern and Yucatán bobwhites are more closely related to one another than to the crested bobwhite. The deep divergence between the two complexes indicates that the phylogenetic split occurred prior to the Pleistocene (2.5 million years ago). The northern–Yucatán bobwhite complex exhibited little phylogeographic structure and showed some evidence of range or demographic expansion during the Pleistocene, whereas the crested bobwhite was composed of four geographically and genetically distinct clades in Central and South America. The scaled quail displayed low genetic diversity and little structure across its limited range, possibly as a consequence of recent demographic growth and expansion after passing through a severe bottleneck. The Gambel’s quail is composed of two genetically distinct, but geographically overlapping clades. Both clades exhibited evidence of past demographic growth. Overall, little concordance between subspecies taxonomy and genetic data was observed in any of the species studied, except in the crested bobwhite
Parasitological survey of scaled quail from West Texas
No full textThe scaled quail (Callipepla squamata) has experienced a long-term decline and the influence of parasites is being considered as a possible cause. Little research has been conducted on the impact of parasites on scaled quail in any part of its range and even less parasite research has been conducted in west Texas. The objectives of this study were to determine the influences of host age, host sex, host weight, hunting season of collection and Palmer's Drought Severity Index (PDSI) on helminth infections and to document pathological responses of infected tissues. A total of 204 scaled quail was collected from west Texas. Thirty-four were trapped in cooperation with the intensive disease and parasite quail study Operation Idiopathic Decline (OID) conducted in 2012 and 2013. Additionally, hunters donated 170 quail during the 2012- 2013, 2013-2014 and 2014-2015 Texas quail hunting seasons. Histological analyses were conducted on scaled quail intraorbital glands (n = 4) and ceca (n = 6). Because of small sample size, OID collected scaled quail were not examined statistically. Considering the entire OID and hunter donation samples together, seven helminth species were found with a total count of 13,315 individuals. Aulonocephalus pennula dominated numerically with 12,655 individuals (95% of total) followed by Oxyspirura petrowi with 477 individuals (4% of total) and Procyrnea pileata with 184 individuals (0.8% of total). The three most common species (>25% prevalence) were statistically tested; however, A. pennula was extremely common and variation of prevalence could not be detected. Pro cyrnea pileata and 0. petrowi were more prevalent in the 2013-2014 season and P. pileata prevalence was greater in females than males. Mean abundance of A. pennula varied by age, season of collection and the interaction of age and season of collection. Mean abundance of 0. petrowi was influenced by host age, season of collection, the interaction of age and season of collection and host weight. Procyrnea pileata abundance was not influenced by any of the measured variables. Species richness among host age, host sex and season of collection was similar. Assessment of the intraorbital glands found an increase of lymphocytes, indicating an immune response and acinar atrophy in the Harderian glands sampled when 0. petrowi was present. Additionally, cecal villi of samples with 213 and 396 A. pennula individuals displayed an increase of lymphocytes and plasma cells and experienced localized epithelium separation. This study provides baseline information that will benefit parasitologists, biologists and managers in future helminth research and management
Micro-magnetic resonance imaging study of live quail embryos during embryonic development
No full textEggs containing live Japanese quail embryos were imaged using micro-magnetic resonance imaging (μMRI) at 24-h intervals from Day 0 to 8, the period during which the main body axis is being laid down and organogenesis is taking place. Considerable detail of non-embryonic structures such as the latebra was revealed at early stages but the embryo could only be visualized around Day 3. Three-dimensional (3D) changes in embryo length and volume were quantified and also changes in volume in the extra- and non-embryonic components. The embryo increased in length by 43% and nearly trebled in volume between Day 4 and Day 5. Although the amount of yolk remained fairly constant over the first 5 days, the amount of albumen decreases significantly and was replaced by extra-embryonic fluid (EEF). 1H longitudinal (T1) and transverse (T2) relaxation times of different regions within the eggs were determined over the first 6 days of development. The T2 measurements mirrored the changes in image intensity observed, which can be related to the aqueous protein concentrations. In addition, a comparison of the development of Day 0 to 3 quail embryos exposed to radiofrequency (rf) pulses, 7 T static magnetic fields and magnetic field gradients for an average of 7 h with the development of control embryos did not reveal any gross changes, thus confirming that μMRI is a suitable tool for following the development of live avian embryos over time from the earliest stages
Montezuma quail habitat and occupancy in the Southern Edwards Plateau of Texas
No full textMontezuma quail (Cyrtonyx montezumae) historically occupied nearly every county within the Edwards Plateau ecoregion of Texas, USA. Over the last 2 centuries overgrazing, lack of natural fire and subsequent encroachment of woody cover has constricted the Montezuma quail’s distribution to a 5 county area centered on Edwards County, Texas. Very little is known about this quail, and much of what we know has come from populations in southern New Mexico, southern Arizona and Mexico. The objective of this research was to identify variables effecting detection and use of Montezuma quail and to develop a predictive distribution model to identify areas potentially holding Montezuma quail. Call-back surveys were conducted April– August 2015 and March–August 2016 at 60 stratified sampling locations on private ranches known to be occupied by Montezuma quail. Detection of Montezuma quail was most effected by temperature. Site use by Montezuma quail was most influenced by bunchgrass density (pooled use). Maximum entropy was used to develop a predictive distribution model which identified 601,629 ha of the Edwards Plateau with a probability of use ≥0.5
Habitat use and resource selection by scaled quail in the South Texas Plains
No full textHabitat loss and fragmentation have been proposed as the driving factors for the scaled quail (Callipepla squamata) decline throughout their geographic range. However, the importance of undisturbed plant communities for the chestnut-bellied subspecies (C.s. castanogastris) in South Texas is unclear and their selection of thermal and vegetation characteristics at relocation and nest sites is poorly documented. My objectives were to determine 1) the importance of undisturbed plant communities in home range selection and 2) thermal and vegetation variables important in organism-centered and nest-site selection. Scaled quail were monitored using radiotelemetry during April – August, 2013 – 2014 in LaSalle County, Texas, USA. Geographic information software (GIS) was used to calculate proportions of plant communities in used and random home ranges. Thermal and vegetation variables were sampled at organism-centered locations, nests, and random locations. Scaled quail used undisturbed plant communities more, and exotic-grass invaded communities less, than was available for home range selection. Ground-surface temperatures >42° C negatively influenced organism-centered site selection and birds used structurally complex, undisturbed plant communities to reduce heat loads. Prickly pear cactus and diverse, complex structured woody vegetation were used for nesting sites. Brush clearing and planting exotic grasses may reduce and fragment habitat for scaled quail by removing thermal and escape cover and impeding movement among undisturbed habitat patches
Comparative habitat use of Montezuma Quail in the Edwards Plateau and Trans-Pecos ecoregions of Texas
No full textMontezuma quail (Cyrtonyx montezumae) are a secretive and understudied bird species inhabiting the southwestern United States (Texas, Arizona, and New Mexico), and populations have been declining for the past century. Two populations of Montezuma quail are found in Texas, and they occupy the Edwards Plateau and Trans-Pecos Mountains and Basins ecoregions. A common vegetation characteristic found in both ecoregions is juniper, with Ashe (Juniperus ashei) and alligator juniper (Juniperus deppeana) being the dominant juniper species in the Edwards Plateau and Trans-Pecos, respectively. Ashe juniper has increased over the past several decades and created dense stands of woody cover leading to a decline in usable space for Montezuma quail, while alligator juniper occurs throughout the western portion of the Montezuma quail’s geographic distribution. Comparisons of Montezuma quail use of juniper species between these 2 ecoregions have not been conducted. I compared Montezuma quail habitat use at the micro-scale (16-m radius) for both ecoregions and at the macro-scale (350-m radius) for the Edwards Plateau. During 2018–2020, I collected vegetation data at used locations of quail in the Edwards Plateau (n = 24) and the Trans-Pecos (n = 13), as well as at random locations (n = 41 and n = 29, respectively). Resource selection analyses indicated avoidance of areas with ≥ 20‒30% Ashe juniper cover at both scales in the Edwards Plateau and a selection/indifference to alligator juniper cover (≥ 8% to ≤ 50%) in the Trans-Pecos at the micro-scale. Land managers in should reduce dense stands of Ashe juniper to create usable space for Montezuma quail in the Edwards Plateau but no management may be necessary in the Trans-Pecos
Impacts of oil-and-gas development in the Eagle Ford Shale on quail and other birds
No full textMany North American birds have been declining across their geographical ranges for the past few decades due to habitat loss and fragmentation. South Texas is one of the last remaining strongholds for northern bobwhite (Colinus virginianus; hereafter bobwhite) and scaled quail (Callipepla squamata) populations in the US. The region is also important for conservation of all birds because it contains large tracts of unfragmented habitat, mostly in the form of privatelyowned ranches. However, the recent development of the Eagle Ford Shale hydrocarbon formation in this region has the potential to negatively impact quail and other avian species and their habitat. The objective of this study was to determine how bobwhites, scaled quail, and other avian species respond to localized oil-and-gas disturbance. My study took place on 2 private ranches located in Dimmit County, Texas during March – September (2015 and 2016). I trapped and radio-marked bobwhites and scaled quail in 2 focal areas along an oil-and-gas exploration corridor (disturbed treatment) and 2 focal areas along corridors where relatively little Eagle Ford Shale exploration activities have occurred (relatively undisturbed treatment). Point counts and nest searches for all birds were also conducted in these focal areas. Indirect oil-and-gas disturbance was quantified with a sound level meter and traffic counters. Noise propagation for 2 frequencies (250 Hz and 1,000 Hz) was modeled during each month of the study with field measurements and noise propagation software. I examined quail site selection to roads and sound levels, and quail home range and core area size, seasonal adult survival, nest success, and density in response to disturbance from oiland- gas activity. Bobwhites and scaled quail selected for areas 0 m–200 m and >425 m from the primary corridor road, respectively. In the relatively undisturbed area, bobwhites and scaled quail selected for areas 0 m–425 m and 0 m–300 m from primary roads, respectively. Bobwhites and scaled quail avoided sites with sound levels >1.6 dB and >2.2 dB above ambient levels at the 250 Hz frequency level, respectively. At the 1,000 Hz frequency level, bobwhites and scaled quail avoided sites with sound levels >2 dB and >3.2 dB above ambient levels, respectively. I found no linear relationship between home range and core area size and disturbance (sound levels and vehicle passage rates) for either species of quail (P > 0.359 for bobwhites, P > 0.127 for scaled quail), although mean home range and core area sizes of both quail species were numerically larger in disturbed area than undisturbed areas. Seven-month (Mar – Sep) survival probability for bobwhites and scaled quail was 11.9 ± 5.1% and 43.8 ± 9.0%, respectively. I found no relationship between seasonal survival probability and disturbance for either species of quail. Probability of nest success for bobwhites and scaled quail was 49.8 ± 12.4% and 38.1 ± 18.9%, respectively. For bobwhites, probability of nest success decreased as sound levels (dB) at 250 Hz increased. I found no relationship between probability of nest success and disturbance for scaled quail. However, average sound levels (at 250 Hz) at scaled quail nests only ranged from ambient to 1 dB above ambient, whereas levels at bobwhite nests were over a larger range. Density of all quail was not significantly different between disturbed and undisturbed areas. I examined avian nest-site selection, nest success, and density in response to oil-and-gas disturbance. Birds preferred nest sites with sound levels 0 dB–2.6 dB above ambient levels at the 1,000 Hz frequency level in both study years. I found no effect of treatment (P = 0.144) on apparent nest success. However, apparent nest success was 28% lower in disturbed areas (41.2 ± 11.9%) than in undisturbed areas (69.2 ± 12.8%). I found no relationship between disturbance (noise levels and vehicle passage rates) and apparent nest success. Density of all bird species was greater in disturbed areas (6.0 birds/ha) than in undisturbed areas (1.8 birds/ha). Grassland associates and cosmopolitan species constituted a greater proportion of total density in disturbed areas than in undisturbed areas. In addition to outright habitat loss due to conversions of rangeland to oil-and-gas infrastructure, the apparent indirect influence of oil-and-gas activity on site use and demographics of quail and other avian species is an important management consideration as production in the Eagle Ford Shale region continues
Rapid manufacturing technique used in the development of a regenerative pump impeller
No full textThis paper presents a method of rapid manufacture used in the development of a regenerative pump impeller. Rapid manufacturing technology was used to create complex impeller blade profiles for testing as part of a regenerative pump optimisation process. Regenerative pumps are the subject of increased interest in industry. Ten modified impeller blade profiles, from the standard radial configuration, were evaluated with the use of computational fluid dynamics and experimental testing. Prototype impellers were needed for experimental validation of the CFD results. The manufacture of the complex blade profiles using conventional milling techniques is a considerable challenge for skilled machinists. The complexity of the modified blade profiles would normally necessitate the use of expensive CNC machining with 5 axis capability. With an impeller less than 75 mm in diameter and a maximum blade thickness of 1.3mm, a rapid manufacturing technique enabled production of complex blade profiles that were dimensionally accurate and structurally robust enough for testing. As more advanced rapid prototyping machines become available in the study in the future, e.g. 3D photopolymer jetting machine, the quality of the parts particularly in terms of surface finish will improve and the amount of post processing operations will reduce. This technique offers the possibility to produce components of increased complexity whilst ensuring quality, strength, performance and speed of manufacture. The ability to manufacture complex blade profiles that are robust enough for testing, in a rapid and cost effective manner is proving essential in the overall design optimisation process for the pump
Survey of quail parasites in South Texas
No full textThe northern bobwhite (Colinus virginianus) and scaled quail (Callipepla squamata) are in decline across their ranges in Texas. The cause of these declines has long been thought to be habitat loss and fragmentation. However, there is speculation that factors such as parasites may play a role in the decline of bobwhite populations. South Texas, a region with some of the highest bobwhite densities in the state, has had limited studies on quail parasites. The objective of this study was to determine relationships of helminth infections to host age, sex, mass, and season of collection. Nine helminth species were documented in bobwhites (n = 209) and 7 in scaled quail (n = 23). The cecal nematode Auloncephalus pennula was numerically dominant and had the greatest prevalence, abundance, and intensity in bobwhites and scaled quail. The prevalence and abundance of A. pennula was higher in adult bobwhites than juveniles. The abundance of A. pennula was also higher in bobwhites with greater mass within each age cohort. Host sex was not a significant factor. Prevalence of A. pennula was higher during the 2012– 2013 hunting season than the 2013–2014 season. This research provides insight regarding helminth infections in quails from South Texas
Frequency of quail detection with respect to the distance from the ‘quail caller’ (10 m increments).
No full textFrequency of quail detection with respect to the distance from the ‘quail caller’ (10 m increments).</p
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