Long‐term Production and Profitability from Grazing Cattle in the Northern Mixed GrassPrairie

Conventional wisdom among rangeland professionals has been that for long‐term sustainability of grazing livestock operations, rangeland should be kept in high good to low excellent range condition. Our objective was to analyze production parameters, economic costs, returns, and profit using data generated over a thirty‐four year period (1969‐2002) from grazing a Clayey range site in the mixed‐grass prairie of western South Dakota with variable stocking rates required to maintain pastures in low‐fair, good, and excellent range condition classes. Cattle weights were measured at turnout and at the end of the grazing season. Gross income per acre was calculated by multiplying total gain per acre times price using historical National Agricultural Statistics Services feeder cattle prices. Annual variable costs were estimated from a historical yearling cattle budget developed by South Dakota State University (SDSU) agricultural economists. All economic values were adjusted to a constant dollar using the Bureau of Labor Statistics’ Consumer Price Index. Stocking rate, average daily gain, total gain, net profit, gross revenue, and annual costs per acre varied among range condition classes. Net income for low‐fair range condition ($11.18 per acre) and good range condition ($11.86 per acre) were not different, but both were greater (P \u3c 0.01) than excellent range condition ($ 9.31 per acre). Over the life of the study, real profit (adjusted for inflation) steadily increased (P \u3c 0.01) for the low‐fair and good treatments while it remained level for the excellent treatment. Neither drought nor wet springs impacted profit differently for the three treatments. These results support generally observed rancher behavior regarding range condition: to maintain their rangeland in a lower range condition than would be normally recommend by rangeland professionals. Ecosystem goods and services of increasing interest to society and associated with high range condition, such as floristic diversity, hydrologic function, and wildlife cover, come at an opportunity cost to the rancher

Reduced stomatal density in bread wheat leads to increased water-use efficiency

Wheat is a staple crop, frequently cultivated in water-restricted environments. Improving crop water-use efficiency would be desirable if grain yield can be maintained. We investigated whether a decrease in wheat stomatal density via the manipulation of epidermal patterning factor (EPF) gene expression could improve water-use efficiency. Our results show that severe reductions in stomatal density in EPF-overexpressing wheat plants have a detrimental outcome on yields. However, wheat plants with a more moderate reduction in stomatal density (i.e. <50% reduction in stomatal density on leaves prior to tillering) had yields indistinguishable from controls, coupled with an increase in intrinsic water-use efficiency. Yields of these moderately reduced stomatal density plants were also comparable with those of control plants under conditions of drought and elevated CO2. Our data demonstrate that EPF-mediated control of wheat stomatal development follows that observed in other grasses, and we identify the potential of stomatal density as a tool for breeding wheat plants that are better able to withstand water-restricted environments without yield loss

Increased captures of the critically endangered leatherback turtle (Dermochelys coriacea) around New Zealand: the contribution of warming seas and fisher behavior

Five species of sea turtles are known to occur in New Zealand waters, with the leatherback turtle (Dermochelys coriacea) being the most frequently reported. In New Zealand all sea turtles are protected, but there are currently no fisheries bycatch mitigation measures. We describe fishery captures of leatherbacks from Ministry observer and fisher self-reported data. A generalized additive model (GAM) was then used to evaluate which factors might explain the observed year trend in captures. Between fishing years 2007–08 and 2020–21 (years starting 1 October), there were 217 captures of leatherback turtles, an annual average of 15.5. Reported captures increased substantially to 50 in 2020–21. Nearly all (97.7%) captures were reported from surface longline fisheries. Because of sparse observer coverage most captures (85.3%) were self-reported by fishers. Within the main fishery, just 9.4% of the vessels reported 94.5% of the leatherback captures, and one vessel reported 40.4% of all captures. Some non-reporting of captures seems likely. The GAM estimated a higher probability of capture with increasing SST from a constant-over-time spatial pattern of monthly sea surface temperature, and predicted the increase in captures in 2020–21. Much of the increase in bycatch could therefore be explained by the fleet moving into warmer areas where the probability of leatherback capture was higher. Capture mitigation measures could include restricting fishing in turtle ‘hotspot’ times and areas. New Zealand waters should be recognized as an important seasonal foraging ground for leatherback turtles where capture mitigation measures are necessary

Stimulant Medication and Reading Performance

The study examined the sustained effects of methylphenidate on reading performance in a sample of 42 boys, ages 8 to 11, with attention deficit-hyperactivity disorder (ADHD). Two subgroups were formed based on the presence or absence of co-occurring conduct disorders. Subjects were selected on the basis of their positive response to methylphenidate as determined in a series of original medication trials (Forness, Cantwell, Swanson, Hanna, & Youpa, 1991). For the purpose of this study, subjects were placed on their optimal dose of medication for a 6-week period and then tested on measures of oral reading and reading comprehension equivalent to those used in the original trials, retested after a week without medication (placebo), then tested again the following week after return to medication. Only the subgroup with conduct disorders responded, and this response was limited to reading comprehension improvement in only those subjects who also demonstrated improvement in oral reading on original trials. No response differences were found between subjects with or without learning disabilities.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68569/2/10.1177_002221949202500205.pd

Nest and foraging‐site selection in Yellowhammers Emberiza citrinella: implications for chick provisioning

Capsule Vegetation structure and invertebrate abundance interact to influence both foraging sites and nestling provisioning rate; when invertebrate availability is low, adults may take greater risks to provide food for their young. Aims To investigate nesting and foraging ecology in a declining farmland bird whose fledging success is influenced by the availability of invertebrate prey suitable for feeding to offspring, and where perceived predation risk during foraging can be mediated by vegetation structure. Methods Provisioning rates of adult Yellowhammers feeding nestlings were measured at nests on arable farmland. Foraging sites were compared with control sites of both the same and different microhabitats; provisioning rate was related to habitat features of foraging-sites. Results Foraging sites had low vegetation density, probably enhancing detection of predators, or high invertebrate abundance at high vegetation density. Parental provisioning rate decreased with increasing vegetation cover at foraging sites with high invertebrate abundance; conversely, where invertebrate abundance was low, provisioning rate increased with increasing vegetation cover. Conclusions Vegetation structure at foraging sites suggests that a trade-off between predator detection and prey availability influences foraging site selection in Yellowhammers. Associations between parental provisioning rate and vegetation variables suggest that where invertebrate abundance is high birds increase time spent scanning for predators at higher vegetation densities; however, when prey are scarce, adults may take more risks to provide food for their young

Assessing rates of parasite coinfection and spatiotemporal strain variation via metabarcoding: insights for the conservation of European turtle doves Streptopelia turtur

Understanding the frequency, spatiotemporal dynamics and impacts of parasite coinfections is fundamental to developing control measures and predicting disease impacts. The European turtle dove (Streptopelia turtur) is one of Europe's most threatened bird species. High prevalence of infection by the protozoan parasite Trichomonas gallinae has previously been identified, but the role of this and other coinfecting parasites in turtle dove declines remains unclear. Using a high-throughput sequencing approach, we identified seven strains of T. gallinae, including two novel strains, from ITS1/5.8S/ITS2 ribosomal sequences in turtle doves on breeding and wintering grounds, with further intrastrain variation and four novel subtypes revealed by the iron-hydrogenase gene. High spatiotemporal turnover was observed in T. gallinae strain composition, and infection was prevalent in all populations (89%–100%). Coinfection by multiple Trichomonas strains was rarer than expected (1% observed compared to 38.6% expected), suggesting either within-host competition, or high mortality of coinfected individuals. In contrast, coinfection by multiple haemosporidians was common (43%), as was coinfection by haemosporidians and T. gallinae (90%), with positive associations between strains of T. gallinae and Leucocytozoon suggesting a mechanism such as parasite-induced immune modulation. We found no evidence for negative associations between coinfections and host body condition. We suggest that longitudinal studies involving the recapture and investigation of infection status of individuals over their lifespan are crucial to understand the epidemiology of coinfections in natural populations

Mesophyll porosity is modulated by the presence of functional stomata

The formation of stomata and leaf mesophyll airspace must be coordinated to establish an efficient and robust network that facilitates gas exchange for photosynthesis, however the mechanism by which this coordinated development occurs remains unclear. Here, we combine microCT and gas exchange analyses with measures of stomatal size and patterning in a range of wild, domesticated and transgenic lines of wheat and Arabidopsis to show that mesophyll airspace formation is linked to stomatal function in both monocots and eudicots. Our results support the hypothesis that gas flux via stomatal pores influences the degree and spatial patterning of mesophyll airspace formation, and indicate that this relationship has been selected for during the evolution of modern wheat. We propose that the coordination of stomata and mesophyll airspace pattern underpins water use efficiency in crops, providing a target for future improvement

The Generationing of Power: A Comparison of Child-Parent and Sibling Relations in Scotland

The paper concentrates on an exploration of power relations within families. The paper discusses parental power in relation to legitimacy, household resources and children’s anticipated reactions of adult discipline. The nature of sibling power is highlighted before exploring the reciprocal expectations of sibling and child-parent interactions. The paper ends by suggesting that the generationing of power relations can lead to differing degrees of backstage and frontstage performances within the home

Modal mineralogy of CI and CI-like chondrites by X-ray diffraction

The CI chondrites are some of the most hydrated meteorites available to study, making them ideal samples with which to investigate aqueous processes in the early Solar System. Here, we have used position-sensitive-detector X-ray diffraction (PSD-XRD) to quantify the abundance of minerals in bulk samples of the CI chondrite falls Alais, Orgueil and Ivuna, and the Antarctic CI-like chondrites Y-82162 and Y-980115. We find that Alais, Orgueil and Ivuna are dominated by a mixed serpentine/saponite phyllosilicate (81–84 vol%), plus minor magnetite (6–10%), sulphides (4–7%) and carbonates (<3%). This reflects an extended period of aqueous alteration and the near-complete transformation of anhydrous phases into a secondary mineral assemblage. The similarity in total abundance of phyllosilicate suggests that the CI chondrites all experienced the same degree of aqueous alteration on the parent body. In contrast, Y-82162 contains a highly disordered serpentine/saponite phyllosilicate (68 vol%), sulphide (19%), olivine (11%) and magnetite (2%). This mineralogy is distinct from that of the CI chondrites, attesting to both a different starting mineralogy and alteration history. The structure and relatively low abundance of the phyllosilicate, and the high abundance of olivine, are consistent with previous observations that Y-82162 represents CI-like material that following aqueous alteration suffered thermal metamorphism at temperatures >500 °C. Similarly, Y-980115 contains disordered serpentine/saponite (71 vol%), sulphide (19%), olivine (8%) and magnetite (2%), confirming that it too is a thermally metamorphosed CI-like chondrite. We suggest that the CI-like chondrites are derived from a different parent body than the CI chondrites, which underwent short-lived thermal metamorphism due to impacts and/or solar radiation