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Through case studies that link changes in invertebrate populations to changes in bird populations, we suggest how climate change may increasingly impact bird populations through variation in their invertebrate prey. To assess whether invertebrate and bird population declines could be linked and suggest potentially emerging climate change impacts on wildlife. We draw on field experience and case studies to illustrate how potential climate change impacts on invertebrates may cascade to affect bird populations and identify some key research gaps for urgent consideration. We highlight four invertebrate groups which may be sensitive to the impacts of climate change and that have the potential to impact bird populations that feed on them: soil invertebrates, foliar invertebrates, aerial insects, and aquatic invertebrates. Our ability to understand these impacts is hampered by a lack of extensive long-term monitoring data for many invertebrates, and invertebrate data collected at scales that can be related to bird populations. We call for collaboration between entomologists and ornithologists, both non-vocational and professional, to support new empirical research and long-term monitoring initiatives to better link changes in insect populations and birds to inform future decision-making. This will be particularly important to understand likely future increasing climate change pressures on birds. [ABSTRACT FROM AUTHOR]

Among plausible causes for replicability failure, one that has not received sufficient attention is the environment in which the research is conducted. Consisting of the population, equipment, personnel, and various conditions such as location, time, and weather, the research environment can affect treatments and outcomes, and changes in the research environment that occur when an experiment is redone can affect replicability. We examine the extent to which such changes contribute to replicability failure. Our framework is that of an initial experiment that generates the data and a follow-up experiment that is done the same way except for a change in the research environment. We assume that the initial experiment satisfies the assumptions of the two-sample t-statistic and that the follow-up experiment is described by a mixed model which includes environmental parameters. We derive expressions for the effect that the research environment has on power, sample size selection, p-values, and confidence levels. We measure the size of the environmental effect with the environmental effect ratio (EER) which is the ratio of the standard deviations of environment by treatment interaction and error. By varying EER, it is possible to determine conditions that favor replicability and those that do not. [ABSTRACT FROM AUTHOR]

COVID-19 restrictions significantly biased BTO/JNCC/RSPB Breeding Bird Survey coverage across the UK allowing indicative trends to be produced for approximately one-third of species in England only. To investigate the effect that COVID-19 restrictions had on participation in and coverage of the Breeding Bird Survey (BBS), and to quantify the likely impacts on population change reporting based on 2020 data. We determined geographic, seasonal, and habitat coverage for the BBS in 2020 and compared this to previous years, and quantified the scale of biases and reductions in sample size for target species. We degraded existing BBS data (1994–2019) to simulate 2020 coverage and produced population change estimates using three methods applied to the complete and degraded data to assess the impacts of 2020 coverage on emergent trends. In 2020, 49% fewer survey squares were visited compared to 2019. Reductions were greatest in Wales, Scotland, and Northern Ireland, and in the early breeding season, when 90% fewer visits were made. The few early visits completed were on atypical dates and showed marked habitat biases. Individual species were detected in 23–96% fewer squares than normal. Population change estimates derived using routine trend models were negatively biased in up to 96% of species, with errors greatest for species normally detected on early visits. Alternative trend models using visit-specific parameterization or focussing only on late season visits overcame coverage biases for some species. Lockdown restrictions associated with the COVID-19 outbreak meant it was not possible to produce population trend information for UK, Wales, Scotland, or Northern Ireland in 2020. Indicative long-term trends could be produced in England only for a subset of about 40 species. We recommend managers of citizen science schemes undertake similar analyses to assess the scale of coverage biases when unforeseen events cause temporary, but substantial changes, in sampling effort. [ABSTRACT FROM AUTHOR]

Tick infestation increased with temperature and vegetation height, and was negatively correlated with Golden Plover Pluvialis apricaria chick survival, but not growth rates. To examine the factors associated with tick loads on Golden Plover chicks and whether tick loads correlated with the growth rate or short-term survival probability. Twenty-one chicks from eight broods were radio-tagged and recaptured at 4-day intervals to measure tick loads, growth rate and determine survival probability between recaptures. All broods and 90% of chicks (19/21) had ticks present during at least one recapture, and ticks were present on 81% (70/86) of all recaptures. Mean tick load per capture was 9.2 (range 0–45) which was 13 times higher than the only previous comparable study on wader chicks. Tick loads were highest in warmer weather and when chicks moved through areas with taller average field layer vegetation. Tick loads were also correlated with chick age and date. The chick growth rate was highest in warmer weather and at mid-altitudes (400–450 m) but showed no significant correlation with tick load. The probability of a chick surviving between recaptures was positively correlated with chick body condition and negatively correlated with tick load. This study, albeit from one site and with small sample size, recorded high tick loads on Golden Plover chicks. Although unrelated to growth rates, ticks were negatively correlated with chick survival. Further work to identify the mechanism(s) underpinning associations between tick load and survival is required. Prior to considering whether tick control is an effective and justified management for wader conservation, research should first establish whether chick mortality from ticks limits Golden Plover and other wader populations on moorland. [ABSTRACT FROM AUTHOR]

Capsule:Across Britain, breeding Eurasian CurlewNumenius arquataare less numerous and have shown greater population declines in areas with more arable farming, woodland cover and higher generalist predator abundance. Aims:We present the first national-scale analysis of the potential drivers of Curlew population change in Britain, which is needed to guide conservation action for this globally near-threatened, declining species. Methods:Breeding Bird Survey data and environmental predictors were used to model variation in Curlew abundance in 1995–99 and 2007–11, and population change between these periods. Results:Arable farming and woodland cover were negatively associated with Curlew abundance and population declines. Curlew abundance was positively associated with extent of protected area coverage and gamebird numbers. Abundance and population change were positively associated with cooler temperatures and higher summer rainfall, but negatively associated with numbers of generalist predators. Conclusions:We found support for the negative effects of intensive agriculture, forestry, increases in generalist predator populations and climate warming on Curlew abundance and population change. Effective site protection and measures to reduce generalist predator abundance may be important conservation measures, together with improving breeding habitat quality in the wider countryside. [ABSTRACT FROM PUBLISHER]

CapsuleBlack Grouse declines across Scotland were greatest on less heterogeneous moorland, at low to intermediate altitudes and, more weakly, around post-thicket woodland. AimsTo examine correlates of change in abundance of Black Grouse across Scotland. MethodsChanges in abundance within 5-km squares between national surveys in 1995/96 and 2005 were modelled in relation to measures of habitat cover and woodland age derived from satellite imagery. ResultsPopulations across Scotland were most stable where unenclosed moorland comprised rough grassland, intermediate heather cover and at higher altitude. Declines tended to be greatest in squares which had transitioned from pre-thicket to closed-canopy woodland. ConclusionMoorland will be most beneficial where it is heterogeneous in composition, and the role of woodland maturation in driving regional declines has support, albeit more weakly, at a national scale. [ABSTRACT FROM PUBLISHER]

CapsuleAbundance monitoring data suggest that the short-term response of breeding birds to recent warming in Great Britain has been range expansion, caused by poleward shifts of leading range margins and no significant shifts of trailing range margins. AimsTo quantify latitudinal and elevational shifts of breeding bird populations in Great Britain and test for differential shifts in range margins during a period of warming (1994–2009). MethodsWe modelled the population density of 80 species as a smooth function of latitude, longitude, elevation and year. Reference points on the distribution curve were used to describe latitudinal and elevational shifts. ResultsAcross species, poleward shifts in the leading range margin were greater than in the range-centre. The trailing range margin was largely static, providing evidence for significant range expansion. The magnitude of latitudinal range shift lagged behind the equivalent shift in temperature, suggesting that species may be accumulating a climatic debt. There was no evidence for consistent elevational shifts. ConclusionContrary to the generally expected long-term consequences of climate change of range contraction, we show that the short-term response to recent warming has been range expansion. This suggests the mechanisms of short-term and long-term consequences of climate change may differ. [ABSTRACT FROM AUTHOR]

CapsuleHeterogeneous detectability amongst species may impact multi-species bird surveys and if not accounted for, may bias community level conclusions. Estimates of detectability were produced for 195 UK bird species, and detectability was significantly affected by bird size, diet and habitat specialization. AimsTo estimate detectability and understand which species traits may impact detectability. MethodsWe estimated the detectability of 195 species of birds in the UK using distance sampling methods and examined the average detectability of genetically related groups. We tested the significance of species traits in describing variation in detectability, whilst controlling for phylogenetic relationships. ResultsPasseriformes had the lowest median detectability of 0.37 and Charadriiformes the highest median detectability of 0.65, of the seven largest orders considered. Species most associated with closed habitats such as woodland and urban areas had the lowest detectability. Smaller species had lower detectability than larger species. ConclusionHeterogeneity in species detectability could lead to biased conclusions, particularly when calculating multi-species indices such as species richness or diversity. Accounting for detectability will be most important in studies that cover a wide range of habitat types or a diverse spread of taxa. [ABSTRACT FROM AUTHOR]

Capsule Accounting for changes in detectability over time which could invalidate population trends for common and widespread breeding birds in the UK, resulted in little change in trends for the majority of species considered. Aims To examine whether detectability has a significant influence on population trends for common and widespread breeding birds in the UK. Methods Using data collected over 16 years of the UK Breeding Bird Survey (1994–2009) and focusing on a random sample of 20 common and widespread bird species, we examine the extent to which controlling for temporal change in detectability would influence national population trends. Results Population trends were significantly different for only 2 of the 20 species, Common Blackbird and Winter Wren. This difference corresponds to an apparent fall off in detectability of these species between 2005 and 2009. For the remaining species, controlling for detectability resulted in no significant difference in population trends. Conclusions The importance of detectability should be examined as part of any long-term monitoring programme. However, currently we do not find sufficient support for routinely incorporating detectability into population trends for widespread and abundant breeding birds in the UK. [ABSTRACT FROM PUBLISHER]

Capsule No evidence for sustained declines in abundance or re-distribution of two key upland bird species on a wind farm site in the first three years of operation. Aims To describe changes in the abundance and distribution of birds on an upland wind farm during the first three years of operation. Methods Surveys to map the distribution of breeding birds were conducted at the wind farm and a nearby control site in 2006 and 2009. Results Only Willow Ptarmigan (Red Grouse) Lagopus lagopus scotica and European Golden Plover Pluvialis apricaria were sufficiently numerous for analysis. There was no significant difference in the change in abundance of either species between the wind farm and control site, and no evidence that changes in the species' distribution were related to wind farm infrastructure. Conclusions Upland wind farms may not necessarily result in declines in bird populations in the operational phase. Similar studies across a range of sites should be conducted and published to examine the factors that determine the response of birds to particular developments. [ABSTRACT FROM AUTHOR]

Capsule Declines of upland waders were associated with habitat cover, forest edge exposure, grouse moor management intensity and crow abundance. Aims To explore whether changes in the abundance of five wader species in the uplands correlate with the three key hypotheses proposed for their declines. Methods Using data from repeat upland bird surveys, we examined at two spatial scales (region and plot) if population changes correlate with vegetation cover, forest edge exposure, grouse moor management intensity or crow abundance. Results For Northern Lapwings Vanellus vanellus and Eurasian Curlews Numenius arquata, there was an association between declines and broad-scale vegetation cover; declines being greatest on heather-dominated plots. Exposure to forest edge was associated with declines of European Golden Plovers Pluvialis apricaria and Common Snipe Galinago galinago at the plot scale, and of Northern Lapwings at the regional scale. More intensive grouse moor management was associated with lower declines in Northern Lapwings at both the plot and regional scale, but with greater declines in European Golden Plovers at the plot scale. Northern Lapwings also declined most on plots with the highest Carrion Crow Corvus corone abundance. Conclusion These analyses represent the first attempt to assess empirically the balance of evidence for different broad-scale land-use and habitat-related drivers of upland wader population declines, providing pointers to their respective roles in driving these declines. [ABSTRACT FROM AUTHOR]

Capsule Variations in the composition, structure and heterogeneity of moorland vegetation are shown to affect the abundance of eight of nine moorland bird species, with implications for grazing management. Aims To determine how variation in vegetation characteristics affects breeding bird abundance on moorlands. Methods Bird and habitat data from 85 2-km² plots in south Scotland and northern England were analysed using multivariate analysis to disentangle vegetation effects from confounding site and management effects. Results Of nine species studied in detail, Red Grouse Lagopus lagopus scoticus and Stonechat Saxicola torquata were associated with Heather Calluna vulgaris, although both favoured some heterogeneity in cover. Meadow Pipit Anthus pratensis demonstrated a curvilinear relationship with Heather cover, whilst both Curlew Nurnenius arquata and Snipe Gallinago gallinago were most abundant where vegetation structure was relatively heterogeneous. Skylark Alauda arvensis and Golden Plover Pluvialis apricaria were positively associated with short vegetation, in particular short grass and short dwarf shrub cover, respectively. Whinchat Saxicola rubetra was associated with dense vegetation, particularly Bracken Pteridium aquilinum, but no strong vegetation effects were detected for Wheatear Oenanthe oenanthe. Six of the nine species showed positive associations with vegetation typical of wet conditions. Conclusions Moorland birds vary in their preferences for particular compositional and structural vegetation features, and management promoting heterogeneity and wetland vegetation is likely to support a diverse bird community and benefit certain key species. Losses of Heather cover in recent decades, primarily from increased grazing levels, appear likely to have reduced habitat availability for only two of the nine species studied. [ABSTRACT FROM AUTHOR]

Capsule Counts least susceptible to observer effects were those within 25 m of a transect and the total number along a transect, with observer effects greater for distance sampling. [ABSTRACT FROM AUTHOR]

The article discusses the common methods of surveying Golden Plover, a bird. Although difficult to census accurately, standard techniques have focused upon the mapping of bird locations whilst walking variable routes. A more general technique for surveying all moorland waders surveyed areas to a maximum distance of 100 m twice in a season, once from early April to mid-May, and again from mid-May to the end of June. Maps of bird locations from the two visits are compared to estimate the number of breeding pairs within a geographical unit. Any Golden Plover survey method should be properly calibrated for a range of scenarios, including populations in which off-duty birds do not feed on pasture and therefore are more likely to be detected, and northern populations where the breeding season will be short and more synchronous. The precise level of intensity required for a particular survey will depend upon the resources available and the degree of accuracy required. Where accurate, site specific counts are required, a more intensive approach may be needed, using either pre-nesting or post-hatching surveys, the accuracy of which should be tested with further calibration.

This article presents an action plan for establishing a system of quality assurance for Croatian higher education. The action plan is forward-looking rather than retrospective and draws on experiences with adopting continuous improvement practices in Australia, Turkey, and the United States. Numerous authors have explored the challenges facing Croatian higher education, so we do not duplicate that task. We propose to adopt a continuous improvement system which will help modernize the system of education in Croatia. [ABSTRACT FROM AUTHOR]

ABSTRACT Strategists must manage a number of factors when executing strategy. One of the most important of these is organizational culture. And to successfully manage organizational culture, strategists must manage cultural artifacts. Cultural artifacts include myths and sagas about company successes and the heroes and heroines within the company; language systems and metaphors; rituals, ceremonies, and symbols; certain physical attributes such as the use of space, interior and exterior design, and equipment; and the defining values and norms. In managing execution by managing culture, strategists usually think in terms of managing values and norms. But as it turns out, if they don't also manage existing cultural artifacts, then they build in barriers to failure. Why? Because existing cultural artifacts support the old strategy not the new one. To be successful, strategists must create new cultural artifacts or modify the existing ones so that they support the new strategy. This article uses the case of the successful turnaround at Continental Airlines to demonstrate precisely how managing cultural artifacts enhances strategy execution. [ABSTRACT FROM AUTHOR]

Capsule The best estimate of breeding success was a mean of 0.57 fledglings per pair, which when combined with adult survival rates, successfully explained the observed population trend. Aims To quantify Golden Plover breeding success on a moor managed for shooting Red Grouse Lagopus lagopus. Methods An intensive study recorded the fate of individual Golden Plover nests and, using radiotelemetry, chicks. The factors associated with mortality were examined, allowing the construction of a model of breeding success. Adult survival was estimated from return rates of colour-ringed birds. Results Estimated rates of daily nest survival during laying (0.8636) were significantly lower than during incubation (0.9913). The daily survival rate of chicks less than nine days (0.8868) was significantly lower than for older chicks (0.9792). A population model based on these parameters overestimated the rate of nest losses, but accurately described brood survival and fledging success. Although predation rates were low, poor survival of young chicks through starvation or exposure suggest other factors were limiting breeding success at the study site. Conclusions Predation rates of Golden Plover nests and chicks can be low on moorlands managed for shooting Red Grouse. However, in the absence of predation, other factors may still reduce chick survival and limit breeding success. [ABSTRACT FROM AUTHOR]

Capsule The change was correlated with environmental, habitat and management variables. Aims To identify factors correlated with a population decline and range contraction between 1988-91 and 1999. Methods Regression models are used to describe the variation in Ring Ouzel abundance in 1988-91, and the change in Ring Ouzel abundance between 1988-91 and 1999. Results The abundance of Ring Ouzels in 1988-91 was negatively correlated with improved pasture, but positively with heather/smooth grass mosaic and Nardus/Molinia grassland. There was also a positive quadratic correlation with rock cover. A decline in Ring Ouzels between 1988-91 and 1999 was most likely on tetrads with shallow gradients, and outside of a 350-750 m altitudinal range. The change in ouzel numbers was also negatively correlated with both the initial area of conifer forest and heather/smooth grass mosaic. The rate of loss was greatest in those areas with a low Ring Ouzel abundance in 1988-91, although this effect was non-significant once habitat was accounted for. Conclusions The abundance of Ring Ouzels was linked to heather-grass mosaics, while declines were greater in tetrads lacking topographical features known to be selected by nesting ouzels. The negative relationship between forestry and population change suggests that large-scale afforestation of the uplands is a cause of concern. [ABSTRACT FROM AUTHOR]

Examines the significance of Peruvian poet C é sar Vallejo to his country. Influence of Vallejo on other Peruvian poets; Contributions of Vallejo to Peruvian poetry; Information on his works.

Comments on the articles written by James J. Higgins and Robert V. Hogg on statistical programs for the undergraduate statistics major. Status of statistics as an undergraduate discipline; Need for an identity for the undergraduate discipline; Use of continuous quality improvement (CQI) on statistics programs; Response from Higgins and Hogg.

Describes a multivariate permutation tests as a replacement of Hotelling's test in prescribed circumstances. Situations arising in behavioral science research; Comparison between permutation and Hotelling's tests; Details on the power advantages of permutation tests.

Focuses on surface integral techniques in statistics. Presentation of surface integral theorems useful in distribution theory; Application of the results on standard problems in mathematical statistics; Justification of theorems using intuitive geometrical ideas.

A man who tells secrets or stories must think of who is hearing or reading them, for a story has as many versions as it has readers. Everyone takes what he wants or can from it and thus changes it to his measure. Some pick out parts and reject the rest, some strain the story through the mesh of prejudice, some paint it with their own delight. A story must have some points of contact with the reader to make him feel at home in it. Only then can he accept wonders. [ABSTRACT FROM PUBLISHER]

Statistical properties of the bivariate exponential distribution are investigated. Maximum likelihood and method of moments type estimates are obtained and compared with the estimates given by Arnold. The method of moments type estimates are easy to compute and highly efficient, whereas the maximum likelihood estimates are computationally inconvenient. The problem of testing for correlation in the bivariate exponential distribution is also investigated. [ABSTRACT FROM AUTHOR]

Objective: Driver drowsiness contributes to a substantial number of fatal and nonfatal crashes, with recent estimates attributing up to 21% of fatal crashes to drowsiness. This article describes recent NHTSA research on in-vehicle drowsiness countermeasures. Recent advances in technology and state detection algorithms have shown success in detecting drowsiness using a variety of data sources, including camera-based eye tracking, steering wheel position, yaw rate, and vehicle lane position. However, detection is just the first step in reducing drowsy driving crashes. Countermeasures are also needed to provide feedback to the driver, modify driver behavior, and prevent crashes. The goal of this study was to evaluate the effectiveness of in-vehicle drowsiness countermeasures in reducing drowsy lane departures. The tested countermeasures included different warning modalities in either a discrete or staged interface.Methods: Data were collected from 72 young adult drivers (age 21-32) in the high-fidelity full-motion National Advanced Driving Simulator. Drivers completed a 45-min simulated nighttime drive at 2 time points, late night and early morning, where drowsiness was manipulated by continuous hours awake. Forty-eight drivers were exposed to one of 6 countermeasures that varied along 2 dimensions, type and modality. The countermeasures relied on a steering-based drowsiness detection algorithm developed in prior NHTSA research. Twenty-four drivers received no countermeasure and were used as a baseline comparison. System effectiveness was measured by lane departures and standard deviation in lateral position (SDLP).Results: There was a reduction in drowsy lane departure frequency and lane position variability for drivers with countermeasures compared to the baseline no-countermeasure group. Importantly, the data suggest that multistage alerts, which provide an indication of increasing urgency, were more effective in reducing drowsy lane departures than single-stage discrete alerts, particularly during early morning drives when drivers were drowsier.Conclusions: The results indicate that simple in-vehicle countermeasures, such as an auditory-visual coffee cup icon, can reduce the frequency of drowsy lane departures in the context of relatively short drives. An important next step is to evaluate the impact of drowsiness countermeasures in the context of longer, multiple-hour drives. In these cases, it may not be possible to keep drivers awake via feedback warnings and it is important to understand whether countermeasures prompt drivers to stop to rest. The next phase of this research project will examine the role of drowsiness countermeasures over longer drives using a protocol that replicates the motivational conditions of drowsy driving. [ABSTRACT FROM AUTHOR]

Constructed wetlands provide good removals of BOD, COD, suspended solids, heavy metals, and pathogens from wastewaters being treated in them. However, although they are widely used in cold climates, winter operability often presents problems, and they normally only remove part of nitrogen and phosphorus nutrients in wastewaters being treated in them. What is needed was a new type of constructed wetland which removes nutrients as well as it does other contaminants, which operates better in cold weather, and which is able to handle especially difficult-to-treat wastewaters. The answer may be found with engineered wetlands, a type of constructed wetland in which process conditions and/or operations are modified, manipulated and/or controlled, in contrast to the more passive operation of ordinary constructed wetlands. Although the names "engineered wetland" and "constructed wetland" are sometimes used interchangeably, it is appropriate to define the former more narrowly by limiting the engineered wetland designation to apply only to the less passive situation. All engineered wetlands are constructed wetlands, but not all constructed wetlands are engineered ones. Constructed wetland systems may be "engineered" in many ways. For example, influent streams may be varied in flow rate (or periodically turned off); effluents from various points in the wetland system may be recycled to other points, ordinary substrates may be replaced with special ones having specific qualities (e.g., the ability to permanently chemically adsorb certain pollutants from wastewaters passingthrough them); things may be added at certain points (e.g., heat, chemicals, air); and/or wetland vegetation may be selected for its phytoremediating properties. This paper describes a new sub-surface flow (SSF) engineered wetland biological/environmental technology (ecotechnology) known as BioReactor Engineered Wetland for wastewater treatment (BREW). It presents the results from bench scale, mesocosm testingw [ABSTRACT FROM AUTHOR]