scholarly journals Habitat Preferences of Pinyon-Juniper Specialists Near the Limit of Their Geographic Range

The Condor ◽  
2001 ◽  
Vol 103 (2) ◽  
pp. 322-331 ◽  
Author(s):  
David C. Pavlacky ◽  
Stanley H. Anderson
Keyword(s):  
Colorado Plateau ◽  
Habitat Preferences ◽  
Rock Outcrops ◽  
Juniperus Osteosperma ◽  
The Family ◽  
Pinyon Pine ◽  
Selection For ◽  
Utah Juniper ◽  
Breeding Seasons ◽  
Polioptila Caerulea

Abstract We investigated habitat preferences for five pinyon-juniper specialists during the 1998 and 1999 breeding seasons in Utah juniper (Juniperus osteosperma) woodlands of southwestern Wyoming. We compared avian use and availability of vegetation features using univariate and multivariate analysis to detect selection for vegetative features of pinyon-juniper specialists near the northeastern range boundary of pinyon-juniper habitat on the Colorado Plateau. Gray Flycatchers (Empidonax wrightii), Juniper Titmice (Baeolophus griseus), and Bewick's Wrens (Thryomanes bewickii) preferred woodlands with high overstory juniper cover. The Juniper Titmouse was associated with senescent trees, Blue-gray Gnatcatcher (Polioptila caerulea) with rock outcrops and shrubs in the family Rosaceae, and Black-throated Gray Warbler (Dendroica nigrescens) with pinyon pine (Pinus edulis). We suggest the geographic distribution of four of five pinyon-juniper specialists is limited by the occurrence of pinyon pine in semiarid woodlands on the northeastern Colorado Plateau. The geographic limit for Blue-gray Gnatcatchers in this region may correspond to the presence of mountain mahogany in the woodland understory. The conservation of pinyon-juniper specialists in southwestern Wyoming will benefit from the maintenance of successional processes, particularly those that perpetuate mature woodlands with a pinyon pine component.

scholarly journals Abundance and Habitat Preferences of Gray Vireos (Vireo Vicinior) on the Colorado Plateau

The Auk ◽  
2006 ◽  
Vol 123 (1) ◽  
pp. 33-44
Author(s):  
Scott Schlossberg
Keyword(s):  
Additional Data ◽  
Colorado Plateau ◽  
Conservation Status ◽  
Habitat Preferences ◽  
Breeding Habitat ◽  
Short Term ◽  
Northern Arizona ◽  
Pinyon Pine ◽  
Primary Habitat

Abstract The Gray Vireo (Vireo vicinior; hereafter “vireo”) is a little-studied songbird with small breeding and wintering ranges. Because of uncertainty about vireo populations, conservationists are concerned about the future of this species. The goal of the present study was to provide new data on the ecology of the vireo to help determine its conservation status. During May and June 2001, I studied breeding habitat selection by vireos on the Colorado Plateau in northern Arizona and southern Utah. I surveyed for vireos and collected vegetation data on 31 transects in pinyon-juniper (Pinus edulis-Juniperus spp.) woodlands throughout this region. Estimated density of vireos was 0.064 ± 0.011 (mean ± SE) birds ha−1. Analysis at two scales showed that the vireo’s primary habitat preference was for areas where junipers predominate over pinyon pine. Vireos also preferred areas with some shrub cover, and they increased with the prevalence of sagebrush (Artemisia tridentata) among shrubs. Additionally, vireos were more common at lower elevations, an effect that was largely independent of vegetation characters. Habitats preferred by vireos are widespread in the southwestern United States and may be increasing in extent as woodlands expand into grasslands and shrublands. On the basis of these results, I suggest that vireo populations are relatively safe, at least for the short term. Additional data on vireo demography are needed to ensure the long-term conservation of this species. Abundancia y Preferencias de Hábitat de Vireo vicinior en la Planicie de Colorado

Flies of the family Dolichopodidae (Diptera: Brachycera), excluding the Microphorinae and Parathalassinae, from the Maltese Islands with notes on their habitats and phenology

2021 ◽  
Vol 30 (1) ◽  
pp. 25-39
Author(s):  
M.J. Ebejer
Keyword(s):  
Habitat Preferences ◽  
Maltese Islands ◽  
The Family ◽  
First Time

All 41 species of Dolichopodidae in 22 genera (excluding one species each in the subfamilies Microphorinae and Parathalassinae) known to occur on the Maltese Islands are reviewed, with 31 of these being recorded for the first time. Habitat preferences and flight periods of the species recorded are tabulated and discussed.

The Biological Model for Paleoclimatic Interpretation of Mesa Verde Tree-Ring Series

1965 ◽  
Vol 19 ◽  
pp. 101-121 ◽  
Author(s):  
Harold C. Fritts ◽  
David G. Smith ◽  
Marvin A. Stokes
Keyword(s):  
Tree Ring ◽  
High Temperatures ◽  
Ring Width ◽  
Douglas Fir ◽  
Biological Model ◽  
Tree Ring Chronology ◽  
Mesa Verde ◽  
Pinyon Pine ◽  
Utah Juniper ◽  
Low Precipitation

AbstractRing-width chronologies in Douglas-fir, pinyon pine, and Utah juniper show some distinctly different characteristics and exhibit highly predictable relationships with variations in climate. Narrow rings in Douglas-fir are largely the result of low precipitation and high temperatures of the previous June, low precipitation during August through February, low precipitation and low temperatures during March through May, and low precipitation and high temperatures of the current June. Narrow rings in pinyon pine are largely a function of low precipitation from October through May, but high July temperatures near the end of the growing season may also exert an influence. Narrow rings in Utah juniper are the result of low precipitation and high temperatures during the previous October through November, low precipitation during December through February, and low precipitation and high temperatures during March through May. A biological model for these relationships is proposed. The tree-ring chronology from A.D. 1273 through 1285 exhibits a clearly defined drought which exceeds in length and intensity any dry period occurring since A.D. 1673. A comparison of the chronologies from species which are influenced differently by summer precipitation indicates that during this period both summers and winters must have been dry. However, the A.D. 1273-1285 drought at Mesa Verde was surpassed by six other droughts of greater intensity during the period A.D. 500–1300. The A.D. 1273–1285 drought may be only one of several factors in a chain of events which led to the decline of prehistoric population in the Mesa Verde.

scholarly journals Influence of parentage upon growth in Ostrea edulis: evidence for inbreeding depression

2000 ◽  
Vol 76 (2) ◽  
pp. 159-168 ◽  
Author(s):  
YAMAMA NACIRI-GRAVEN ◽  
SOPHIE LAUNEY ◽  
NICOLAS LEBAYON ◽  
ANDRE GERARD ◽  
JEAN-PIERRE BAUD
Keyword(s):  
Inbreeding Depression ◽  
Genetic Relatedness ◽  
Protozoan Parasite ◽  
Control Population ◽  
Ostrea Edulis ◽  
The Family ◽  
Bonamia Ostreae ◽  
Sib Families ◽  
The Mean ◽  
Selection For

Genetic variability for growth was analysed in three populations of Ostrea edulis, selected for resistance to the protozoan parasite Bonamia ostreae. This study was undertaken first to determine the potential for selection for growth in populations that have never been selected for this character, and second to estimate heterosis versus inbreeding depression. Growth was monitored in culture for 10 months. The selected populations (namely S85-G3, S89I-G2 and S89W-G2), their crossbred population and a control population were composed of full-sib families whose parents were already genotyped using five microsatellite markers. This genotyping allowed the estimation of genetic relatedness among pairs of parents. The parents' relatedness was then correlated with the growth performance of their offspring within each of the three populations, and inbreeding depression was estimated. The population effect for growth was highly significant, with the crossbred population having the highest growth rate, followed by S89I-G2 and S89W-G2, S85-G3 and the control population. The within-populations family effect was also highly significant, indicating, as well as the high value for heritability at the family level (between 0·57 and 0·92), that a potential for a further selection for growth still exists within the three populations. Estimates of inbreeding depression (relative to the mean, for complete inbreeding) were high (1 for S891-G2, 0·44 for S89W-G2 and between 0·02 and 0·43 for S85-G3), which correlates with the apparent heterosis for growth observed in the crossbred population. These results are discussed in the context of the future management of the selected populations.

Simultaneous instance and feature selection for improving prediction in special education data

2017 ◽  
Vol 51 (3) ◽  
pp. 278-297 ◽  
Author(s):  
Yenny Villuendas-Rey ◽  
Carmen Rey-Benguría ◽  
Miltiadis Lytras ◽  
Cornelio Yáñez-Márquez ◽  
Oscar Camacho-Nieto
Keyword(s):  
Feature Selection ◽  
Data Sets ◽  
Feature Selection Technique ◽  
Similarity Functions ◽  
Content Type ◽  
Education Data ◽  
Multiple Feature ◽  
The Family ◽  
Selection For

Purpose The purpose of this paper is to improve the classification of families having children with affective-behavioral maladies, and thus giving the families a suitable orientation. Design/methodology/approach The proposed methodology includes three steps. Step 1 addresses initial data preprocessing, by noise filtering or data condensation. Step 2 performs a multiple feature sets selection, by using genetic algorithms and rough sets. Finally, Step 3 merges the candidate solutions and obtains the selected features and instances. Findings The new proposal show very good results on the family data (with 100 percent of correct classifications). It also obtained accurate results over a variety of repository data sets. The proposed approach is suitable for dealing with non-symmetric similarity functions, as well as with high-dimensionality mixed and incomplete data. Originality/value Previous work in the state of the art only considers instance selection to preprocess the schools for children with affective-behavioral maladies data. This paper explores using a new combined instance and feature selection technique to select relevant instances and features, leading to better classification, and to a simplification of the data.

scholarly journals Orobanche bohemica Čelak. (Orobanchaceae) at the eastern limit of its geographical range: new data on its distribution in Poland

2012 ◽  
Vol 26 (1) ◽  
pp. 53-59 ◽  
Author(s):  
Renata Piwowarczyk
Keyword(s):  
Western Europe ◽  
Habitat Preferences ◽  
Distribution Range ◽  
Taxonomic Position ◽  
Geographical Range ◽  
Diagnostic Features ◽  
Host Abundance ◽  
The Family ◽  
Distribution In Europe

Abstract A new locality of Orobanche bohemica Čelak., one of the rarest representatives of the family Orobanchaceae in Central and South-Western Europe, is reported from Poland. This is the first confirmed record of the species in Poland. It is the easternmost site known for the species, so it extends its distribution range. The species was recorded in Zawiercie-Bzów in the Czȩstochowa Upland (Wyżyna Czȩstochowska) in July 2010. Its host, abundance, and habitat preferences at the new locality are described, and a supplemented map of its distribution in Europe and Poland is given. Its taxonomic position as well as some diagnostic features that distinguish O.bohemica from O.purpurea are also discussed.

scholarly journals Breeding-Season Decisions, Renesting, and Annual Fecundity of Female Eastern Meadowlarks (Sturnella Magna) in Southeastern Illinois

The Auk ◽  
2004 ◽  
Vol 121 (3) ◽  
pp. 796-805 ◽  
Author(s):  
Eric L. Kershner ◽  
Jeffery W. Walk ◽  
Richard E. Warner
Keyword(s):  
Site Selection ◽  
Population Biology ◽  
Nest Site ◽  
Adult Survival ◽  
Demographic Parameter ◽  
Site Characteristics ◽  
Sturnella Magna ◽  
Double Brooding ◽  
Selection For ◽  
Breeding Seasons

Abstract Annual fecundity is a demographic parameter that is elemental to population biology, but accurate measures of fecundity are rarely obtained. We used radiotelemetry to follow female Eastern Meadowlarks (Sturnella magna) throughout the 1999-2000 breeding seasons in southeastern Illinois to estimate their annual fecundity and assess if the outcome of initial nesting attempts affected site selection for subsequent nests. Thirty-four females built 52 nests (1.53 ± 0.12 nests female−1), but only 21 females (62%) fledged young. Only 44% of females renested at the study site, and more females (53%) emigrated after successfully fledging young from an initial nest than after failing in their first attempt (21%). Nest-site characteristics were similar between successful and failed nests for both initial and subsequent attempts. Females that failed during first attempts did not change nest characteristics for renests. Given that few females were double-brooded and that unsuccessful females did not persistently renest, annual fecundity for females nesting at the study site was between 1.27 ± 0.38 and 1.36 ± 0.37 female young year−1. On the basis of our fecundity measure, we estimated that annual adult survival of 59–61% was necessary for maintenance of a stable population (λ = 1.0). Failure of most females to attempt to raise two broods suggests that double brooding carries substantial costs for meadowlarks.

Shoes for Children: A Review

PEDIATRICS ◽  
1991 ◽  
Vol 88 (2) ◽  
pp. 371-375
Author(s):  
Lynn T. Staheli
Keyword(s):  
Load Distribution ◽  
Medical Profession ◽  
Primary Role ◽  
Shock Absorption ◽  
The Family ◽  
Selection For ◽  
Foot Development

1. Optimum foot development occurs in the barefoot environment. 2. The primary role of shoes is to protect the foot from injury and infection. 3. Stiff and compressive footwear may cause deformity, weakness, and loss of mobility. 4. The term "corrective shoes" is a misnomer. 5. Shock absorption, load distribution, and elevation are valid indications for shoe modifications. 6. Shoe selection for children should be based on the barefoot model. 7. Physicians should avoid and discourage the commercialization and "media"-ization of footwear. Merchandizing of the "corrective shoe" is harmful to the child, expensive for the family, and a discredit to the medical profession.

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