bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spotted Towhee Population Dynamics in a Riparian Restoration Context
Authors: Small Stacy L. , Thompson Frank R. , Geupel Geoffrey R. , Faaborg John 
Published: September 2019

AbstractWe investigated factors at multiple scales that might influence nest predation risk for Spotted Towhees (Pipilo maculatus) along the Sacramento River, California, within the context of large-scale riparian habitat restoration. We used the logistic-exposure method and Akaike's information criterion (AIC) for model selection to compare predator search, predator abundance, restoration, and temporal effects hypotheses. Our candidate models represented restoration, temporal, nest activity, nest concealment, agriculture, and flood effects. Restoration sites did function as breeding habitat, with nest survival comparable to mature forest sites and some young being produced. The best-supported models contained the covariates cowbird young in host nest and calendar date. All supported models contained the covariate cowbird young, the only variable with a strong effect. In contrast to our prediction, nest survival increased with cowbird young in the nest, implicating adult cowbirds in nest predation events. Nest survival declined throughout the breeding season and increased marginally with nest concealment. We calculated the finite rate of population increase (λ), using a model that incorporated nest success estimates for parasitized and unparasitized nests, double brooding, the locally observed cowbird parasitism rate for Spotted Towhees, number of young fledged from successful parasitized and unparasitized nests, adult survival and a range of juvenile survival values, estimated as percentages of adult survival. Values of λ did not approach the replacement level of one, indicating that this population is not self-sustaining. We recommend extensive habitat restoration in the floodplain landscape, ideally in conjunction with cowbird control, to reduce nest predation and parasitism pressures.
Response of Bird Species Densities to Habitat Structure and Fire History Along a Midwestern Open–Forest Gradient
Authors: Grundel Ralph , Pavlovic Noel B. 
Published: September 2019

Abstract
Oak savannas were historically common but are currently rare in the Midwestern United States. We assessed possible associations of bird species with savannas and other threatened habitats in the region by relating fire frequency and vegetation characteristics to seasonal densities of 72 bird species distributed across an open–forest gradient in northwestern Indiana. About one-third of the species did not exhibit statistically significant relationships with any combination of seven vegetation characteristics that included vegetation cover in five vertical strata, dead tree density, and tree height. For 40% of the remaining species, models best predicting species density incorporated tree density. Therefore, management based solely on manipulating tree density may not be an adequate strategy for managing bird populations along this open–forest gradient. Few species exhibited sharp peaks in predicted density under habitat conditions expected in restored savannas, suggesting that few savanna specialists occur among Midwestern bird species. When fire frequency, measured over fifteen years, was added to vegetation characteristics as a predictor of species density, it was incorporated into models for about one-quarter of species, suggesting that fire may modify habitat characteristics in ways that are important for birds but not captured by the structural habitat variables measured. Among those species, similar numbers had peaks in predicted density at low, intermediate, or high fire frequency. For species suggested by previous studies to have a preference for oak savannas along the open–forest gradient, estimated density was maximized at an average fire return interval of about one fire every three years.
The Ornithology of the Real Expedición Botánica a Nueva España (1787–1803): An Analysis of the Manuscripts of José Mariano Mociño
Authors: Navarro-Sigüenza Adolfo G. , Townsend Peterson A. , Ángel Puig-Samper Miguel , Zamudio Graciela 
Published: September 2019

AbstractUntil recently, a major gap has existed in our knowledge regarding Mexican bird information from the Real Expedición Botánica a Nueva España in the late 1700s. This expedition (1787–1803) was commanded by Martín de Sessé; the Mexican scientist José Mariano Mociño joined the group in 1790, but his ornithological findings were never published and have long been considered lost. However, study of the Sessé-Mociño ornithological results began in 1979 with the appearance of a small collection of original paintings, apparently from the expedition. Later, in 1997, unpublished manuscripts were discovered in the library of the Museo Nacional de Ciencias Naturales, Madrid that included descriptions of many bird species, again apparently Sessé-Mociño material. These discoveries, covering an important portion of the overall ornithological results of the expedition, make possible a broader study of the Sessé-Mociño ornithology: a taxonomic list using modern nomenclature, an analysis of the correspondence between the paintings and the manuscripts, and conclusions regarding the provenance of those materials. Of a total of 83 paintings available, we were able to identify 78 to species, and 5 only to family. In the manuscripts, 290 species were treated, but for 27, the descriptions were fragmentary and insufficient for identification; of the remaining 263 species, we arrived at a species-level identification for 242, and identified the remainder to genus (19) or family (2). The recent discovery of these ornithological texts and paintings offers a unique view of the history of ornithology as well as of the environmental history of Mexico.
Species Differences in the Songs of the Critically Endangered Niceforo's Wren and the Related Rufous-and-White Wren
Authors: Valderrama Sandra V. , Parra Jorge E. , Mennill Daniel J. 
Published: September 2019

Abstract
Niceforo's Wrens (Thryothorus nicefori) and Rufous-and-white Wrens (Thryothorus rufalbus) are closely related Neotropical birds. Niceforo's Wrens, critically endangered endemic Colombian songbirds, are generally considered a sister species to Rufous-and-white Wrens, although some have suggested that they may represent a well-marked race. A careful comparison of the two taxa has never been conducted. Here we present a thorough study of the songs of male Niceforo's and Rufous-and-white Wrens based on recordings collected throughout both species' geographic ranges. Both species sing low-pitched songs composed of varied pure tone whistles. Niceforo's Wren songs are shorter and simpler with fewer syllables and syllable types; they have higher frequency trills and terminal syllables; and they have distinctive terminal syllables with a broader bandwidth, higher frequency of maximum amplitude, and a larger number of frequency modulations. Discriminant analysis based on fine structural details of songs differentiates the two species. In a subspecies-level discriminant analysis, all five subspecies of Rufous-and-white Wren cluster together and are distinct from Niceforo's Wren. Comparisons of morphometric measurements and plumage features reveal parallel differences in body size (Niceforo's Wrens are larger for most measurements) and plumage color (Niceforo's Wrens are more gray than Rufous-and-white Wrens). This study is the first to compare Rufous-and-white versus Niceforo's Wrens with a quantitative approach and supports the idea that these taxa are best understood as distinct species.
Genetic Characterization of Common Eiders Breeding in the Yukon-Kuskokwim Delta, Alaska
Authors: Sonsthagen Sarah A. , Talbot Sandy L. , McCRACKEN Kevin G. 
Published: September 2019

AbstractWe assessed population genetic subdivision among four colonies of Common Eiders (Somateria mollissima v-nigrum) breeding in the Yukon-Kuskokwim Delta (YKD), Alaska, using microsatellite genotypes and DNA sequences with differing modes of inheritance. Significant, albeit low, levels of genetic differentiation were observed between mainland populations and Kigigak Island for nuclear intron lamin A and mitochondrial DNA (mtDNA) control region. Intercolony variation in haplotypic frequencies also was observed at mtDNA. Positive growth signatures assayed from microsatellites, nuclear introns, and mtDNA indicate recent colonization of the YKD, and may explain the low levels of structuring observed. Gene flow estimates based on microsatellites, nuclear introns, and mtDNA suggest asymmetrical gene flow between mainland colonies and Kigigak Island, with more individuals on average dispersing from mainland populations to Kigigak Island than vice versa. The directionality of gene flow observed may be explained by the colonization of the YKD from northern glacial refugia or by YKD metapopulation dynamics.
Breeding Ecology of the Altamira Oriole in the Lower Rio Grande Valley, Texas
Authors: Werner Scott M. , Hejl Sallie J. , Brush Timothy 
Published: September 2019

AbstractDuring 2002–2003, we studied the breeding ecology of the Altamira Oriole (Icterus gularis), a permanent resident that builds pendulous nests in remnant tracts of Tamaulipan brushland in the Lower Rio Grande Valley, Texas. We found 76 active oriole nests, seven of which were reused for second broods, for a total of 83 nesting attempts. Nearly 20% of the breeding individuals in our sample were subadults (second-year orioles). Using a microvideo camera, we were able to estimate incubation and nestling periods of 12.5 and 15.5 days, respectively. Fifty-nine percent of nests fledged at least one young, with successful nests averaging 2.3 fledglings. Failed nests were all intact, indicating that predators entered through the small opening in the top of the nest. Six nests fledged Bronzed Cowbirds (Molothrus aeneus), although two of these nests produced orioles as well. Vegetation analysis suggested that orioles preferred the tallest trees in the study sites in which to place their nests. A greater number of fallen logs was also a predictor of nest sites, which agrees with previous studies suggesting that orioles prefer open woodlands and edges. Formerly vast, dense forests in the Lower Rio Grande Valley have degraded into open woodlands, perhaps benefiting Altamira Orioles during the last 50 years. However, because of the oriole's preference for tall trees, continued degradation of forested tracts may not be beneficial to this species.
Nestling Immunocompetence is Affected by Captivity but not Investigator Handling
Authors: Butler Michael W. , Dufty Alfred M. 
Published: September 2019

Abstract
Environmental conditions during the neonatal period can affect the growth, physiology, behavior, and immune function of birds. In many avian studies the nestling environment includes investigator handling of young, which may be stressful. While neonatal handling is known to affect the adult phenotype in rats, the effects of handling on development have rarely been examined in wild birds. We examined the effect of short, repeated periods of neonatal handling on avian growth and immune system development. We subjected American Kestrels (Falco sparverius) and European Starlings (Sturnus vulgaris) to 15 min of daily investigator handling throughout the nestling period, while controls remained undisturbed. Immediately prior to fledging we assessed cutaneous immunity, humoral immunity, mass, and degree of fluctuating asymmetry. Daily handling did not significantly affect any of these measurements. We also addressed the possibility that treatment differences would appear only when birds were challenged with a more substantial stressor by bringing birds into captivity for 24 hr. Captivity did not affect mass, but significantly lowered the cutaneous immune response, although this was independent of treatment. Therefore, brief periods of investigator handling did not appear to affect immune or morphological development in these species, whereas 24 hr of captivity resulted in suppressed cutaneous immune responses.
Power to Detect Trend in Short-Term Time Series of Bird Abundance
Authors: Thogmartin Wayne E. , Gray Brian R. , Gallagher Maureen , Young Neal , Rohweder Jason J. , Knutson Melinda G. 
Published: September 2019

Abstract
Avian point counts for population monitoring are often collected over a short timespan (e.g., 3–5 years). We examined whether power was adequate (power ≥0.80) in short-duration studies to warrant the calculation of trend estimates. We modeled power to detect trends in abundance indices of eight bird species occurring across three floodplain habitats (wet prairie, early successional forest, and mature forest) as a function of trend magnitude, sample size, and species-specific sampling and among-year variance components. Point counts (5 min) were collected from 365 locations distributed among 10 study sites along the lower Missouri River; counts were collected over the period 2002 to 2004. For all study species, power appeared adequate to detect trends in studies of short duration (three years) at a single site when exponential declines were relatively large in magnitude (more than −5% year−1) and the sample of point counts per year was ≥30. Efforts to monitor avian trends with point counts in small managed lands (i.e., refuges and parks) should recognize this sample size restriction by including point counts from offsite locations as a means of obtaining sufficient numbers of samples per strata. Trends of less than −5% year−1 are not likely to be consistently detected for most species over the short term, but short-term monitoring may still be useful as the basis for comparisons with future surveys.
Approximating Variance of Demographic Parameters Using the Delta Method: A Reference for Avian Biologists
Authors: Powell Larkin A. 
Published: September 2019

AbstractAvian biologists routinely estimate sampling variance for parameter estimates such as daily nest survival, fecundity, annual survival, and density. However, many biologists are not certain of methods to derive sampling variance for parameters when survival rates change temporal scales. Similar methods are needed to obtain sampling variance when biologists combine parameter estimates to calculate an indirect demographic parameter, such as population growth rate. The delta method is a useful technique for approximating sampling variance when the desired demographic parameter is a function of at least one other demographic parameter. However, the delta method is rarely taught in most graduate-level biology or ecology courses, and application of this method may be discouraged by seemingly daunting formulas in reference books. Here, I provide five examples of sampling variance approximations for common situations encountered by avian ecologists, with step-by-step explanations of the equations involved.
The Family Behavior of California Quail: A Molecular Analysis
Authors: Calkins Jennifer D. 
Published: September 2019

AbstractDuring the breeding season, California Quail (Callipepla californica) form two types of groups: those with a single associated adult female (single family groups), and those with more than one associated female (communal family groups). Although single family groups are assumed to be the result of a monogamous pairing of the associated male and female, additional males often associate with these groups. I conducted a preliminary investigation of the genetic relationship among the adults and young in California Quail families using three single-locus microsatellite markers. Both male and female adults were excluded as being the parents of some proportion of the associated young. Females had higher exclusion rates in communal than in single families, while there was no difference for males. A limited number of young were excluded from being the offspring of any of the adults associated with their family. In the first of three study years, adults were more related to one another in families than they were to the population; this relationship disappeared in subsequent years, possibly as a result of disturbance on site. These results suggest that families form, in part, as a result of factors other than direct genetic parentage. These factors might include selection for increasing group size, intermittent kin selection, and proximate factors related to the gregarious behavior of California Quail.
Hypoxia Probably Does not Explain Short Incubation Periods of Woodpeckers
Authors: Wiebe Karen L. 
Published: September 2019

Abstract
I tested the hypothesis that hypoxia in tree cavities causes the unusually short incubation periods characteristic of woodpeckers. I compared saturated O2 levels in ambient air to O2 levels in 13 unoccupied and 14 occupied nest cavities of the Northern Flicker (Colaptes auratus). Oxygen in unoccupied cavities did not differ from ambient levels, whereas O2 in cavities with an incubating adult was 2.2% lower than in saturated air. However, the magnitude of the decrease (20.5% oxygen in occupied cavities compared to 21.0% O2 in saturated air) is small compared to variation in the partial pressure of O2 caused by altitude. This suggests that O2 depletion is not a major selective force on embryonic development times for birds nesting in tree cavities. Alternative hypotheses for short incubation periods of woodpeckers include sexual selection on females and sibling competition.
Fruit Preference, Parasitism, and Offspring Fitness of Fopius arisanus (Hymenoptera: Braconidae) Exposed to Bactrocera dorsalis' (Diptera: Tephritidae) Infested Fruit Species
Authors: Nanga Nanga S , Hanna R , Gnanvossou D , Fotso Kuate A , Fiaboe K K M , Djieto-Lordon C 
Published: September 2019

AbstractFopius arisanus (Sonan) (Hymenoptera: Braconidae) is a koinobiont solitary parasitoid of various fruit flies, particularly those in the genus Bactrocera. Researchers introduced F. arisanus into Africa for the biological control of Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), a pest of a wide range of fruit trees and vegetables. However, the suitability of host fruit species as egg-laying substrates for parasitoid development remains poorly investigated in tropical Africa. The present study examines the preference and performance of F. arisanus on B. dorsalis reared on eleven fruit species through laboratory choice-test trials. We assessed the oviposition activity, parasitism rate, developmental time, and offspring fitness of F. arisanus on nine cultivated and two wild host fruits species. Oviposition attempts were higher on Psidium guajava (L.) (Myrtales: Myrtaceae) and Mangifera indica (L.) (Sapindales: Anacardiaceae) than on the other host fruits tested. The wasp parasitized host eggs in P. guajava in no-choice experiments. Psidium guajava, Irvingia wombulu (Vermoesen) (Malpighiales: Irvingiaceae), and Irvingia gabonensis (Aubry_Lecomte) Baill (Malpighiales: Irvingiaceae) were suitable for parasitism in choice tests. Of all host fruits tested, the body and hind tibia lengths of both parasitoid sexes emerging from M. indica were longer than on the others. The female ovipositor was long on Annona squamosa (L.) (Magnoliales: annonaceae) and short on Eribotrya japonica ([Thunb.] Lindl.; Rosales: Rosaceae). We obtained the longest preimaginal developmental time for both sexes on E. japonica and the shortest for females and males on Carica papaya (L.) (Brassicales: Caricaceae). These results demonstrate the ability of some tested fruit species to serve for the permanent establishment of F. arisanus in the field.
Ventricular response to dobutamine stress cardiac magnetic resonance imaging is associated with adverse outcome during 8-year follow-up in patients with repaired Tetralogy of Fallot
Authors: van den Bosch Eva , Cuypers Judith A A E , Luijnenburg Saskia E , Duppen Nienke , Boersma Eric , Budde Ricardo P J , Krestin Gabriel P , Blom Nico A , Breur Hans M P J , Snoeren Miranda M , Roos-Hesselink Jolien W , Kapusta Livia , Helbing Willem A 
Published: September 2019

Abstract

Aims
The aim of this study was to evaluate the possible value of dobutamine stress cardiac magnetic resonance imaging (CMR) to predict adverse outcome in Tetralogy of Fallot (TOF) patients.

Methods and results
In previous prospective multicentre studies, TOF patients underwent low-dose dobutamine stress CMR (7.5 µg/kg/min). Subsequently, during regular-care patient follow-up, patients were assessed for reaching the composite endpoint (cardiac death, arrhythmia-related hospitalization, or cardioversion/ablation, VO2 max ≤65% of predicted). A normal stress response was defined as a decrease in end-systolic volume (ESV) and increase in ejection fraction. The relative parameter change during stress was calculated as relative parameter change = [(parameterstress − parameterrest)/parameterrest] * 100. The predictive value of dobutamine stress CMR for the composite endpoint was determined using time-to-event analyses (Kaplan–Meier) and Cox proportional hazard analysis. We studied 100 patients [67 (67%) male, median age at baseline CMR 17.8 years (interquartile range 13.5–34.0), age at TOF repair 0.9 years (0.6–2.1)]. After a median follow-up of 8.6 years (6.7–14.1), 10 patients reached the composite endpoint. An abnormal stress response (30% vs. 4.4%, P = 0.021) was more frequently observed in composite endpoint patients. Also in endpoint patients, the relative decrease in right ventricular ESV decreased less during stress compared with the patients without an endpoint (−17 ± 15 vs. −26 ± 13 %, P = 0.045). Multivariable analyses identified an abnormal stress response (hazard ratio 10.4; 95% confidence interval 2.5–43.7; P = 0.001) as predictor for the composite endpoint.

Conclusion
An abnormal ventricular response to dobutamine stress is associated with adverse outcome in patients with repaired TOF.
From an Unpaid Electricity Bill to the Primacy of EU Law: Gian Galeazzo Stendardi and the Making of Costa v. ENEL
Authors: Arena Amedeo 
Published: September 2019

Abstract
Whilst Costa v. ENEL is the starting point for most accounts of the primacy of EU law, the story of that lawsuit is still relatively unknown. What drove Flaminio Costa to sue his electricity provider over a bill of as little as £1,925 (about €22 in 2019)? Why did the small-claims court of Milan decide to involve both the Italian Constitutional Court and the European Court of Justice in such a ‘petty’ lawsuit? Why did those two courts hand down rulings going in opposite directions? How did the lawsuit end when it came back to the Milan small-claims court? Relying upon previously undisclosed court documents and interviews with some of the actors involved, this article seeks to shed some light on the less-known aspects of the Costa v. ENEL lawsuit, against the background of electricity nationalization in Italy at the height of the Cold War, and to assess the contribution of that lawsuit and of its ‘architect’, Gian Galeazzo Stendardi, to the development of the doctrine of primacy of European Union law.