scholarly journals Life-History Variation and Demography in Western Bluebirds (Sialia Mexicana) in Oregon

The Auk ◽  
2004 ◽  
Vol 121 (1) ◽  
pp. 118-133
Author(s):  
Amber J. Keyser ◽  
Marilynne T. Keyser ◽  
Daniel E. L. Promislow
Keyword(s):  
Conservation Status ◽  
Vital Rates ◽  
Adult Males ◽  
Population Declines ◽  
Life History Variation ◽  
Data Set ◽  
Sialia Mexicana ◽  
Demographic Processes ◽  
Western Bluebirds ◽  
Using Data

Abstract During the seven-year period from 1995 to 2001, we conducted a detailed, demographic study of a population of Western Bluebirds (Sialia mexicana) in Oregon. Using a data set consisting of individual capture histories for ≈8,000 birds, we estimated age-specific and study-year specific survival estimates of adult males and females. High juvenile recruitment enabled us to generate accurate estimates of juvenile survival from fledging to first breeding attempt. We analyzed fecundity patterns, including nesting phenology, clutch success, and overall reproductive success for nearly 1,200 nesting attempts. Temporal variation in survival and fecundity had strong demographic consequences. Asymptotic population growth analysis suggested a slowly growing population. However, variation in vital rates led to population declines even over the relative short timescale of our study, making the conservation status of this species uncertain. In addition to those results, we discuss the costs and benefits of using data collected by volunteers to study demographic processes.

A novel approach to compare pinniped populations across a broad geographic range

2015 ◽  
Vol 72 (2) ◽  
pp. 175-185 ◽  
Author(s):  
Kathryn L. Sweeney ◽  
Kyle W. Shertzer ◽  
Lowell W. Fritz ◽  
Andrew J. Read
Keyword(s):  
Geographic Range ◽  
Aerial Images ◽  
Distribution Model ◽  
Vital Rates ◽  
Adult Males ◽  
Population Declines ◽  
Sea Lions ◽  
Adult Females ◽  
Broad Region ◽  
Site Types

We utilized aerial images and employed photogrammetric methodologies to collect standardized lengths of Steller sea lions (Eumetopias jubatus) terrestrially hauled out. We conducted comparisons among all site types and separately for rookery and haulout site-types between the two distinct population segments (DPSs; eastern and western) and two broad regions within the western DPS experiencing contrasting population abundance trends. An observed adult female index was created from measurements of reproductive females — in the presence of a pup or juvenile — and was applied as a model constraint for “adult females”. We fitted a finite mixture distribution model to the length-frequency data to estimate the proportion population for three delineated age–sex classes (juveniles, adult females, and adult males) and mean length for juveniles and adult males. Estimated proportions reflected what we expected; however, the broad region within the western DPS exhibiting substantial population declines had greater proportion of all age–sex classes on rookery sites than increasing broad region. Adult sea lions were significantly shorter in the eastern DPS than the western area, providing further evidence of morphological differences between the DPSs. We also introduce a less resource-demanding method for estimating population demographics, and potentially vital rates, for pinnipeds across a vast geographic range.

LIFE-HISTORY VARIATION AND DEMOGRAPHY IN WESTERN BLUEBIRDS (SIALIA MEXICANA) IN OREGON

The Auk ◽  
2004 ◽  
Vol 121 (1) ◽  
pp. 118 ◽  
Author(s):  
Amber J. Keyser ◽  
Marilynne T. Keyser ◽  
Daniel E. L. Promislow
Keyword(s):  
Life History ◽  
Life History Variation ◽  
Sialia Mexicana ◽  
Western Bluebirds

scholarly journals Severe declines of Eastern Imperial Eagle Aquila heliaca populations in the Baikal region, Russia: a modern and historical perspective

2007 ◽  
Vol 17 (3) ◽  
pp. 197-209 ◽  
Author(s):  
Vitaliy V. Ryabtsev ◽  
Todd E. Katzner
Keyword(s):  
Lake Baikal ◽  
Conservation Status ◽  
Set Covering ◽  
Population Declines ◽  
Data Set ◽  
Imperial Eagle ◽  
Aquila Heliaca ◽  
Declining Species ◽  
Conservation Concern ◽  
Historical Accounts

AbstractThe Eastern Imperial Eagle (Aquila heliaca), a vulnerable and declining species, is widely but sparsely distributed throughout its range. Because much of that range extends through the Russian-speaking world, relatively little on the species has been published in English. The world's easternmost population of Eastern Imperial Eagles, at Lake Baikal, Russia, is particularly well studied and, because of recent rapid population declines, is of great conservation concern. Here, using a data set covering more than 20 years evaluated in the context of historical accounts published in Russian, we assess recent severe declines in this population and the subsequent changes in its conservation status. In intensively surveyed areas near Lake Baikal, numbers of territories occupied by eagles have declined by 80–100% in the past 20–40 years. Likewise, throughout the entire region, the average number of known occupied and breeding territories were both more than 40% lower in 1998–1999 than they were in 1982–1983. These data suggest severe long-term declines in the population of Baikal's Imperial Eagles. Because we observed only limited decreases in reproductive output, our interpretation of the patterns in these data is that mortality of non-breeding birds (wintering adults and all pre-adults) is the most likely cause for this decline. Addressing the causes of this decline is critical to protect this severely threatened population from extirpation.Восточный могильник (Aquila heliaca), уязвимый и сокращающийся в численности вид, широко, но разрозненно распространен по своему ареалу. В связи с тем, что большая часть его ареала находится в пределах русскоговорящей части мира, относительно мало опубликовано по этому виду на английском языке. Самая восточная группировка могильника находится в Прибайкалье. Она изучена особенно хорошо и из-за быстрого сокращения популяции вызывает особую тревогу и озабоченность природоохранников. Используя более чем >20 летние данные, рассмотренные в контексте исторических сведений опубликованных по-русски, мы оцениваем недавнее серьёзное сокращение этой популяции и последующие изменения в её природоохранном статусе. На территориях, находящихся под интенсивным обследованием в Прибайкалье, количество участков занятых орлами сократилось на 80–100% за последние 20–40 лет. Таким же образом, во всем регионе, среднее количество известных занятых территорий и гнездовых участков в 1998–1999 было на >40% меньше по сравнению с 1982–1983. Эти данные свидетельствуют о серьёзном долговременном сокращении прибайкальской популяции могильника. В связи с тем, что мы наблюдали лишь незначительное снижение результатов размножения, наша интерпретация модели по этим данным приводит к выводу, что смертность неразмножающихся птиц (зимующих взрослых и неполовозрелых птиц) является наиболее вероятной причиной этого сокращения. Выявление причин произошедшего падения численности очень важно для сохранения этой угрожаемой популяции от полного вымирания.

scholarly journals Attitudinal Change, Cohort Replacement, and the Liberalization of Attitudes about Same-sex Relationships, 1973–2018

2021 ◽  
pp. 073112142199485
Author(s):  
Ashley Wendell Kranjac ◽  
Robert L. Wagmiller
Keyword(s):  
Social Change ◽  
General Social Survey ◽  
Individual Change ◽  
Same Sex ◽  
Social Survey ◽  
Same Sex Marriage ◽  
Population Turnover ◽  
Demographic Processes ◽  
Lesbian And Gay Rights ◽  
Using Data

Americans’ attitudes toward same-sex relationships have liberalized considerably over the last 40 years. We examine how the demographic processes generating social change in attitudes toward same-sex relationships changed over time. Using data from the 1973 to 2018 General Social Survey and decomposition techniques, we estimate the relative contributions of intracohort change and cohort replacement to overall social change for three different periods. We examine (1) the period prior to the rapid increase in attitude liberalization toward same-sex marriage rights (1973–1991), (2) the period of contentious debate about same-sex marriage and lesbian and gay rights (1991–2002), and (3) the period of legislative and judicial liberalization at the state and federal levels (2002–2018). We find that both intracohort and intercohort change played positive and significant roles in the liberalization of attitudes toward same-sex relationships in the postlegalization period, but that individual change was more important than population turnover over this period.

scholarly journals Association between Dyslipidemia and Mercury Exposure in Adults

2021 ◽  
Vol 18 (2) ◽  
pp. 775
Author(s):  
Purum Kang ◽  
Hye Young Shin ◽  
Ka Young Kim
Keyword(s):  
Behavioral Interventions ◽  
Dietary Habits ◽  
Subjective Health ◽  
Targeted Prevention ◽  
Adult Males ◽  
Subjective Health Status ◽  
Factors Affecting ◽  
Health And Nutrition ◽  
Metal Levels ◽  
Using Data

Background—Dyslipidemia is one of the prominent risk factors for cardiovascular disease, which is the leading cause of death worldwide. Dyslipidemia has various causes, including metabolic capacity, genetic problems, physical inactivity, and dietary habits. This study aimed to determine the association between dyslipidemia and exposure to heavy metals in adults. Methods—Using data from the seventh Korean National Health and Nutrition Examination Survey (2016–2017), 5345 participants aged ≥20 years who were tested for heavy metal levels were analyzed in this study. Multiple logistic regression was conducted to assess the factors affecting the prevalence of dyslipidemia. Results—The risks of dyslipidemia among all and male participants with mercury (Hg) levels of ≥2.75 μg/L (corresponding to the Korean average level) were 1.273 and 1.699 times higher than in those with levels of <2.75 μg/L, respectively. The factors that significantly affected the dyslipidemia risk were age, household income, body mass index, and subjective health status in both males and females. Conclusions—In adult males, exposure to Hg at higher-than-average levels was positively associated with dyslipidemia. These results provide a basis for targeted prevention strategies for dyslipidemia using lifestyle guidelines for reducing Hg exposure and healthy behavioral interventions.

scholarly journals Multispecies Transcriptomics Data Set of Brugia malayi, Its Wolbachia Endosymbiont wBm, and Aedes aegypti across the B. malayi Life Cycle

2018 ◽  
Vol 7 (18) ◽  
Author(s):  
Matthew Chung ◽  
Laura Teigen ◽  
Silvia Libro ◽  
Robin E. Bromley ◽  
Nikhil Kumar ◽  
...  
Keyword(s):  
Life Cycle ◽  
Aedes Aegypti ◽  
Brugia Malayi ◽  
Adult Males ◽  
Data Set ◽  
Content Type ◽  
Transcriptomics Data ◽  
Wolbachia Endosymbiont ◽  
Males And Females ◽  
Stage 1

Here, we present a comprehensive transcriptomics data set of Brugia malayi, its Wolbachia endosymbiont wBm, and its vector host. This study samples from 16 stages across the entire B. malayi life cycle, including stage 1 through 4 larvae, adult males and females, embryos, immature microfilariae, and mature microfilariae.

Risk-based capital regulation revisited: evidence from the early 2000s

2015 ◽  
Vol 23 (2) ◽  
pp. 115-134 ◽  
Author(s):  
Thomas L. Hogan ◽  
Neil R. Meredith ◽  
Xuhao (Harry) Pan
Keyword(s):  
Design Methodology ◽  
Banking Regulation ◽  
Bank Performance ◽  
Capital Regulation ◽  
Data Set ◽  
Content Type ◽  
Future Performance ◽  
Capital Ratios ◽  
Using Data ◽  
Capital Regulations

Purpose – The purpose of this study is to replicate Avery and Berger’s (1991) analysis using data from 2001 through 2011. Although risk-based capital (RBC) regulation is a key component of US banking regulation, empirical evidence of the effectiveness of these regulations has been mixed. Among the first studies of RBC regulation, Avery and Berger (1991) provide evidence from data on US banks that new RBC regulations outperformed old capital regulations from 1982 through 1989. Design/methodology/approach – Using data from the Federal Reserve’s Call Reports, the authors compare banks’ capital ratios and RBC ratios to five measures of bank performance: income, standard deviation of income, non-performing loans, loan charge-offs and probability of failure. Findings – Consistent with Avery and Berger (1991), the authors find banks’ risk-weighted assets to be significant predictors of their future performance and that RBC ratios outperform regular capital ratios as predictors of risk. Originality/value – The study improves on Avery and Berger (1991) by using an updated data set from 2001 through 2011. The authors also discuss some potential limitations of this method of analysis.

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