Social organization of a species may impact behavior, reproductive ecology, mating system, population genetic structure and overall fitness. A spectrum of sociality exists from solitary individuals to aggregations to integrated, highly related groups. A large body of knowledge exists for sociality and life-history characteristics of ground-dwelling sciurids, including several overarching models to explain the evolution of sociality. These models predict round-tailed ground squirrels (Xerospermophilus tereticaudus) to be solitary based on small body size (~125g), relatively long period of activity (January-June) and a short period of adult-juvenile overlap. However, previous behavioral observations suggest round-tailed ground squirrels have a clustered matrilineal structure with a suite of social behaviors, suggesting that they may represent a unique outlier in ground squirrel sociality models. Within the population of round-tailed ground squirrels at the Casa Grande Ruins National Monument in Coolidge, Arizona, USA, rates of amicable and agonistic interactions between adults were low, with no relationship between relatedness of individuals and rates of social interactions. No population substructure was evident with Bayesian analyses, global or pairwise F(ST) values, and average relatedness among females did not differ from males. Contrary to previous behavioral studies, round-tailed ground squirrels did not have high levels of social behavior, nor did they form significant genetic subpopulation structuring. The active season of round-tailed ground squirrels closely followed patterns of precipitation and peak resource availability. Body mass differed between males and females, across years, and within seasons. Males were heavier than females at emergence, prior to mating and pre-hibernation, but not when females began gestation. Emergence of litters and litter size are related to amount and timing of winter rainfall. Foraging and vigilance behaviors compose 64-66% of the activity budget, but differ in that males spend a greater proportion of time foraging, whereas females spend a greater proportion of time vigilant. Round-tailed ground-squirrels have a polygynandrous mating system. Polygyny was evident in 2004, 2005, and 2006, and multiple paternity occurred in the majority of litters with 2.5 sires/litter; litter size was positively correlated with the number of sires. These findings support predictions generated by sociality models for ground-dwelling squirrels.

No description available.

The red-headed woodpecker is a primary cavity excavator found throughout the Eastern Deciduous Forest and parts of the Great Plains. Although widespread, the red-headed woodpecker is generally considered uncommon, with patchily distributed populations. Over the past 50 years, this species has experienced precipitous, range-wide declines. The red-headed woodpecker uses a variety of cover types to meet resource needs across the annual cycle, ranging from oak savannas and wetlands, to mature beech forests and urban parks. Given their apparent adaptability to such a wide range of habitats, causes of declines are perplexing. To understand and stem declines, recent studies have focused on quantifying this species’ habitat requirements. Most of these studies have focused on a single cover type, often open forests, during the breeding season. However, effective management requires comprehensive knowledge of red-headed woodpecker habitat needs in a variety of cover types across the annual cycle. My thesis seeks to address this knowledge gap. I studied red-headed woodpecker habitat selection during both the breeding and non-breeding seasons at Fort A.P. Hill (FAPH) in Caroline County, Virginia. FAPH contains a variety of cover types that red-headed woodpeckers are known to use for breeding and overwintering, including: wetlands, open forests and closed forests. In Chapter 1, I investigated winter roost-site selection of red-headed woodpeckers in a burned forest stand. My study was the first to quantify winter habitat selection for this species. My aim was to identify variables driving winter roost-site selection at two relevant spatial scales, and estimate their parameter weights using logistic regression. I found that red-headed woodpeckers preferred habitat around the roost tree that contained a higher basal area of snags and mast-producing trees. They differentially selected roost trees based on taxon and decay state. My results indicate that managers should adopt practices that promote snag generation and retention, and mature oak recruitment. In chapter 2, I focused on red-headed woodpecker breeding season habitat requirements, as many other studies have done. However, unlike other studies that investigated habitat selection within a single cover type, I found and characterized nest-sites in three distinct cover types (wetlands, closed forests, open forests). I used a comparative approach to identify cover-type specific nest-habitat thresholds at the landscape, patch and tree scales using boosted regression trees (BRT). Although models at the landscape scale inadequately discriminated between nest and available sites, models at the patch and tree scales achieved excellent discrimination ability. I found that red-headed woodpeckers are consistent in their preference for a number of habitat features at the patch (high medium/large snag density, open canopy) and tree (large diameter tree with less bark) scales, irrespective of cover type context. However, I also found cover-type specific habitat preferences at the patch scale, indicating red-headed woodpeckers are flexible in their selection of features surrounding the nest and responsive to the broader habitat context. My findings suggest that there are a number of habitat features that facilitate breeding for red-headed woodpeckers generally, and management that promotes these features will be effective in a variety of habitat contexts. They also indicate that management can be tailored to provide the most suitable habitat for each of these three commonly used cover types. Together, Chapters 1 and Chapter 2 expand our knowledge of this declining keystone species’ habitat needs across the full annual cycle. But there is still much to know. The choices of habitat selection have consequences. Determining the conditions under which habitat features function to either help or harm populations is a necessary next step. While not a part of this thesis, I am currently investigating the factors that drive nest success among cover types, linking breeding-site selection to population dynamics. I also have behavioral data that will help reveal the mechanisms that either facilitate or constrain the exploitation of food resources across cover types. Finally, the red-headed woodpecker is a facultative migrant that often shifts habitat associations to take advantage of seasonally available resources. Data from my point count surveys—conducted over two successive winter and summer seasons—allow for development of dynamic occupancy models. Modeling shifts in occupancy across seasons will show the habitat factors underlying seasonal shifts. Site-specific differences in colonization, extinction and frequency of occupancy, within seasons but across years, will further our understanding of what constitutes habitat quality for this species, in both the breeding and non-breeding seasons.

Contemporary Greco-Roman wrestling has been rapidly developing – competition among sportsmen has increased, sportsmen s selection system and technologies of athletes preparation of many countries have improved, sporting results have been becoming better, thus all these things stimulate the interest of searching for scientifically approved methods, means and forms of training’s of sportsmen preparation. The study comprises the analysis of the cycle of annual training’s (years 2003-2004) for Greco-Roman wrestlers of the Lithuanian Olympic Sports Centre. The structure of the annual preparation of sportsmen, volume of training’s, intensity, specification, change of physical and functional capacity during the annual cycle of training sessions have been analyzed. The research has shown the content of separate periods of the wrestlers' annual preparation cycle to be too monotonous. A similar number of competitions in terms of percentage in all the periods, comparatively small amount of time spent for general and special physical preparation, almost unchanged intensity of training sessions have been revealed. This is confirmed by wrestlers'minor change of physical and functional capacity in the cycle of annual training sessions. The conclusions of this study allow us to presume that the programme of annual training cycle for Greco-Roman wrestlers at Lithuanian Olympic sports centre must be improved.

No description available.

No description available.

L’objectif de cette thèse est d’étudier les caractéristiques physiques et biogéochimiques de l’habitat épipélagique (0-200 m), ses variabilités spatio-temporelles et les processus qui les gouvernent dans le Golfe de Tadjourah (Djibouti). L’analyse spectrale singulière (SSA) et la fonction empirique orthogonale (EOF) sont appliquées à deux jeux des données satellitales dérivées du radiomètre AVHRR_MetopA et des capteurs de la couleur de l’océan (Modis et Meris). Cette analyse statistique montre que les variabilités de la température de la surface de la mer (SST) et de la concentration de la chlorophylle a (CHLa) sont essentiellement expliquées par les cycles annuels et semi-annuels. Le cycle annuel de la SST montre l’alternance des eaux chaudes d’avril à octobre et des eaux froides de novembre à mars. Le cycle semi-annuel indique une légère baisse de la SST entre juillet et aout, particulièrement à l’ouest du golfe. Pour la CHLa, la variabilité est entièrement représentée par le cycle annuel. Celui-ci indique l’enrichissement des eaux du large avec un fort gradient côte-large de juillet à novembre et une tendance inverse de décembre à juin. En outre, l’analyse spectrale singulière multi-canal (M-SSA) et la fonction de corrélation croisée avec fenêtre de 120 jours, appliquées à l’ensemble des paramètres océanique (SST et CHLa) et atmosphériques (Vent, Température et humidité spécifique de l’air) révèlent que le cycle annuel de la SST est relié aux flux de chaleur à l’interface air-mer. En revanche, le refroidissement des eaux durant juillet-aout associé au pic de la CHLa, a été attribué au phénomène d’upwelling. Dans la seconde partie, afin d’élucider l’influence océanique sur la SST et la CHLa, les structures thermohalines and biogéochemiques de la couche supérieure (0-200 m) sont étudiées à l’aide des données collectées durant juillet-aout 2013, septembre 2013 et Février 2014. Les résultats montrent qu’en juillet-aout, la couche superficielle se composait d’une couche de mélange (CM) s’étendant sur environ 20-30 m de profondeur, suivie d’une thermocline localisée entre 30 and 50 m. La CM était réduite à l’ouest et au sud-est du golfe où le gradient thermique et la CHLa étaient plus élevées proche de la surface. En septembre, cette stratification persistait mais la CM était plus chaude et salée. En Février, la CM s’étendait sur environ 120 m de profondeur et la thermocline était moins prononcée. La comparaison des courants mesurés avec les courants de dérive d’ekman et les courants géostrophiques ont révélé que les structures thermohalines et biogéochimiques sont influencées par les vents de moussons du Sud-Ouest (MSO) et du Nord-Est (MNE). Les MSO qui soufflent de juin à aout, déplacent les eaux de surface du Golfe de Tadjourah vers le Golfe d’Aden et induisent la remontée des eaux profondes à l’ouest et l’intrusion par le nord-est des eaux salée de la thermocline. Celle-ci se rapproche de la surface particulièrement à l’ouest où elle se mélange avec les eaux de surface. En revanche, les vents de moussons du nord-est (MNE) prédominants de novembre à mai, emmènent les eaux froides vers le Golfe de Tadjourah. Le mélange convectif profond épaissit la CM. Cette thèse montre que les vents de moussons et leur renverse saisonnière jouent un rôle crucial dans la stratification de la colonne d’eau et que la topographie du bassin influence et module leurs effets. Durant l’été, la forme en cuvette du bassin et la pente continentale plus allongée à l’ouest favorise l’upwelling à l’ouest du golfe où les anomalies de la SST et de fortes concentrations de la CHLa ont été observées. / The objective of this thesis is to study the physical and biogeochemical characteristics of the pelagic habitat (0-200m), its spatio-temporal variability and the processes that govern them in the Gulf of Tadjourah (Djibouti).Singular spectrum analysis (SSA) and empirical orthogonal function (EOF) were applied to two data sets derived from AVHRR_MetopA radiometry and sea colour sensors (Modis and Meris). These statistical analysis shows that the variability of sea surface temperature (SST) and chlorophyll a concentration (CHLa) are mainly explained by annual and semi-annual cycles. The annual cycle of SST consists of an alternation between warmer (April to October) and cooler (November to March) surface water. The semi-annual cycle shows a slight drop of SST between July and August, particularly in the west of the gulf. For the CHLa, the variability is fully dominated by the annual cycle indicating summer enrichment of seashore water (July-November) with a strong seaward gradient which is reversed from October to May. Multichannel spectrum analysis (M-SSA) and cross correlation function analysis applied to the oceanic (SST, CHL-a) and atmospheric parameters (wind speed, air temperature and humidity) showed that the annual cycle of SST is connected to heat flux at the air-sea interface, while the summer drop of SST and its associated CHL-a increase were attributed to upwelling. In the second part, in order to elucidate this oceanic influence on SST and CHL-a, the vertical thermohaline and biogeochemical structures of the upper layer (0-200 m) were studied using high-resolution hydrographic data collected in July-August 2013, September 2013 and February 2014. During summer, the superficial layer consisted of the mixed layer (ML) extending to a depth of about 20-30 m, followed by the thermocline located between 30 and 50 m depth. The ML was thicker in the west and the southeast where the thermal gradient and chlorophyll a concentrations were particularly high. During September, this stratification persisted but the ML became warmer and saltier and the thermocline moved slightly deeper. In February, the ML extended to about 120 m, and the thermocline was less pronounced. A comparison of the directly measured currents to the wind induced Ekman currents and to geostrophic current profiles revealed that the thermohaline and the biogeochemical features were related to the southeast and northeast monsoon winds (SWM & NEM). Between June and August, the SWM drives surface water from the Gulf of Tadjourah to the Gulf of Aden and thus induces the westward intrusion of high salinity thermocline water from the Gulf of Aden. This near surface flow mixes surface waters in the extreme west of the Gulf of Tadjourah. In contrast, the NEM which blow from September to May, bring cold water toward the Gulf of Tadjourah and thickens the ML through convective mixing. Our thesis shows that the monsoon winds and their seasonal reversal play a crucial role in the stratification of the water column, but that their effects are additionally influenced by basin topography. During summer the bowl-shape of the basin and its elongated slope in the west enhance the upwelling in this area where negative sea surface temperature anomalies and high chlorophyll a concentrations were observed.

Using a 50-year (1951-2000) gridded (1-degree) daily rainfall data set over the Indian land region, we study two main aspects of the Indian monsoon. The first aspect deals with the changing nature of the rainfall annual cycle. This, to our knowledge, is the first attempt at studying the changing behaviour of the Indian monsoon rainfall annual cycle in a systematic way. The annual cycle is defined as a combination of the first few Fourier harmonics of daily rainfall. We then identify five attributes of the annual cycle for each year and location (grid): (a) the day of maximum intensity (peak day); (b) maximum intensity (peak value); (c) beginning; (d) end; and (e) duration of the annual cycle. An extensive statistical analysis of these five attributes over the central Indian region (16.5 – 26.5N; 74.5 – 86.5E) shows that the probability distributions of all attributes, barring the peak value, show a significant change in the last 25 years (1976-2000) compared to the first 25 years (1951-1975). The second issue addressed in this thesis deals with the behaviour of the intraseasonal oscillations in flood and drought years. Previous studies on this issue have been limited to only specific flood or drought years. Our analysis confirms earlier findings such as the northwestward propagation of the 10-20 day ISO. However, we also find, for the first time, based on 9 flood and 9 drought years, that the 20-60 day has an eastward propagation during drought years and remains stationary in flood years. The analysis is primarily statistical in nature, and providing a physical explanation for some of our findings is beyond the scope of our work. Finally, it is worth noting here that without the long-term gridded data, it would have been difficult to assess coherent changes over a large region and long time-period.

Dissertação(mestrado) - Universidade Federal do Rio Grande, Programa de Pós-Graduação em Engenharia Oceânica, Escola de Engenharia, 2004. / Submitted by Lilian M. Silva (lilianmadeirasilva@hotmail.com) on 2013-04-19T22:49:03Z No. of bitstreams: 1 Elementos da Variabilidade Climática no Extremo Sul do Brasil, no Período de 1990 a 2001..pdf: 17940864 bytes, checksum: 36cb3aef5938e868c38a69767e658fa2 (MD5) / Approved for entry into archive by Bruna Vieira(bruninha_vieira@ibest.com.br) on 2013-06-10T18:09:00Z (GMT) No. of bitstreams: 1 Elementos da Variabilidade Climática no Extremo Sul do Brasil, no Período de 1990 a 2001..pdf: 17940864 bytes, checksum: 36cb3aef5938e868c38a69767e658fa2 (MD5) / Made available in DSpace on 2013-06-10T18:09:00Z (GMT). No. of bitstreams: 1 Elementos da Variabilidade Climática no Extremo Sul do Brasil, no Período de 1990 a 2001..pdf: 17940864 bytes, checksum: 36cb3aef5938e868c38a69767e658fa2 (MD5) Previous issue date: 2004 / A variabilidade climática,por exercer grande influência nas civilizações ao longo do tempo, tem atraído a atenção dos pesquisadores contemporâneos que buscam o desenvolvimento de modelos climáticos que consigam reproduzi-la. O objetivo deste estudo é a determinação dos sistemas atmosféricos que causam maior variabilidade climática no extremo sul do Brasil, a fim de prover informações para a elaboração futura de um modelo climático regional. Paratanto, empregou-se a transformada de ondeleta a dois conjuntos de dados, um medido na estação meteorológica convencional situada a 32º04’S e 52º10’W, no período de 1º de janeiro de 1990 a 19 de março de 2001, e outro medido em uma bóia de fundeio localizada aproximadamente a 32º54’S e 50º48’W no oceano Atlântico sudoeste, no período de 1º de junho de 2001 a 8 de maiode 2002. Observou-se que a maior variância de ondeleta em todas as variáveis atmosféricas esteve associada ao ciclo anual, com exceção das componentes zonal e meridional da velocidade do vento e da precipitação. Nestas três variáveis a maior energia foi relacionada à passagem de massas de ar e a formação de sistemas frontais e estes sistemas, por sua vez,assumiram maior importância quando o ciclo anual foi descontado das demais variáveis. Portanto, pode-se inferir que o ciclo anual é o responsável pela maior parte da variabilidade climática no extremo sul do Brasil juntamente com as massas de ar e sistemas frontais. Entretanto, o clima desta região também é afetado pelas oscilações de Madden-Julian, bloqueios atmosféricos e fenômeno El Niño-Oscilação Sul. A associação dos períodos observados na transformada de ondeleta com os eventos atmosféricos foi possível devido a grande eficiência desta metodologia em decompor os sinais em ambos os domínios de tempo e escala. / Climate variability has called the attention of contemporary researchers due to the fact that it exerts large influence on the civilizations throughout time. The development of climatic models aims at reproducing it. The purpose of this study is to establish the atmospheric systems which cause the largest climate variability in the extreme south of Brazil,in order to provide information for the future elaboration of a regional climate model. The wavelet transform was applied to two sets of data: one measured in the conventional meteorological station located at 32º04’S and 52º10’W, from January 1st, 1990 to March 19th, 2001, and the other one measured on a buoy approximately at 32º54’S and 50º48’W in the southwestern Atlantic, from June 1st, 2001 to May 8th, 2002. The largest wavelet variance in all atmospheric variables was associated with the annual cycle, except the zonal and meridional components of the wind velocity and precipitation. In these three ones, the largest variance was related to the passage of air masses and the frontal systems formation. When the annual cycle was subtracted from the series, the largest energy was associated with the passage of air masses and the frontal systems formation. Therefore, it could be inferred that the annual cycle is responsible for most of the climate variability in the region along with the air masses and the frontal systems. However, the climate in this region is also affected by Madden-Julian oscillation, atmospheric blocking, and the El Niño – Southern Oscillation. The wavelet transform is a powerful metodology for signal decomposition, because itallows determining the periodicity and the temporal location of the phenomena. Thus, an association with atmospheric events can be accomplished.

Šiuolaikinės graikų – romėnų imtynės sparčiai vystosi – didėja konkurencija tarp sportininkų, tobulėja sportininkų atrankos sistema. Sparčiai gerėja sportiniai rezultatai, keičiasi taisyklės, o tai skatina ieškoti moksliškai pagristų sportininkų rengimo metodų, priemonių ir treniruotės organizavimo formų. Darbe atlikta Lietuvos olimpinio sporto centro jaunųjų graikų – romėnų imtynininkų rengimo per metinį treniruočių ciklą (2005 – 2006 m.) analizė. Išanalizuota jaunųjų imtynininkų metinio rengimo struktūra, treniruočių krūvių apimtis, specifiškumas, fizinio, funkcinio imtynininkų pajėgumo, bei specialios ištvermės kaita per metinį treniruočių ciklą. Tyrimai parodė, kad imtynininkų metinio rengimo ciklo programos atskirų periodų turinys yra pernelyg vienodas. Mažai besikeičiantis santykinai bendram ir specialiam fiziniam rengimui skiriamas laiko kiekis bei mažai kintantis treniruočių intensyvumas. Tai patvirtina ir imtynininkų fizinio ir funkcinio pajėgumo rodiklių maža kaita metiniame treniruočių cikle. Darbo išvados leidžia daryti prielaidą, kad būtina tobulinti Lietuvos olimpinio sporto cento jaunųjų graikų-romėnų imtynininkų metinio treniruočių ciklo programą. / Contemporary Greco – Roman wrestling has been rapidly developing – competition among sportsmen has increased sportsmen’s selection system. Sporting results have been becoming better, the rules are changing fast and thus all these things stimulate the interest of searching for scientifically approved methods, means and forms of trainings of sportsmen preparation. The study comprises the analysis of the cycle of annual trainings (years 2005-2006) for young Greco – Roman wrestlers of the Lithuanian Olympic Sport Center. The structure of the annual preparation of sportsmen, volume of training, specification, change of physical, functional and special capacity during the annual cycle of training sessions have been analyzed. The research has shown the content of separate periods of the wrestlers’ annual preparation cycle to be too monotonous. Comparatively small amount of time spent for general and special physical preparation. This is confirmed by wrestlers’ minor change of physical and functional capacity in the cycle of annual training session. The conclusion of this study allow us to presume that the plan of annual training cycle for young Greco – Roman wresters at Lithuanian Olympic sport center must be improved.