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The conservation and restoration of pollinators is essential for sustaining viable plant populations in fragmented landscapes because they promote genetic diversity among isolated individuals. As it is expected that populations in remnant and restored forests perpetuate with the passing of the years, restoration programs on highly fragmented agricultural landscapes should be planned with consideration for achieving this purpose. In this work, we evaluated plant-pollinator interactions in restored tropical forests, aiming to establish first, the pollination requirements of plant species in these communities, and secondly, if the pollinator requirements are being fulfilled and the interactions between plants and pollinators are being recovered throughout restoration practices. This work comprises two chapters: On the first one (\"Are the assemblages of tree pollination modes being recovered by tropical forest restoration?\") we did an extensive literature review about the pollination biology of tree species in primary forests, restoration plantings and naturally regenerated forests, to compare and identify patterns on the functional diversity and the assemblages of plant pollination modes. On the second chapter (\"Functional responses and effects from bee communities in restored tropical forests\") we sampled bees (i.e. the most important pollinators) and identified the pollen grains attached to their bodies in primary forests, restoration plantings, disturbed herbaceous areas and sugar cane fields; afterwards we analyzed and compared the functional diversity of bee communities and their floral resources, and the structure of plant-bee interactions, as well as in response to habitat isolation. We found that different restoration practices leaded to changes on patterns of abundance and species proportions of several plant pollination modes, which were stronger in locations under active restoration activities than in naturally regenerated forests. Specifically in the case of bees, we found that the demand for their function as pollinators in restoration plantings was even higher than that in primary forests, since many bee pollinated tree species were being widely and preferably used due to their great colonizing ability, or because of the many other ecosystem functions and services that they provide. We observed that bee communities were getting benefited by such over-representation of bee floral resources, since many species visited more frequently the tree species in restoration plantings than any other habitat. In spite of such preference, the bee abundance and functional diversity of bee communities was not fully recovered in restoration areas, maybe because of other habitat requirements that still remained undersupplied (e.g. nesting resources). Although the functional diversity on bee communities was high in general, only a small part, which was also the most vulnerable (i.e. larger bees that nest above-ground, have different levels of sociality and are polylectics), was the principal in charge of the pollination of the most important plant species in primary and restored forests (i.e. native woody plants, from initial successional stages and with different pollination modes). Throughout this work we analyzed and discussed the implications of these results for the recovery of plant-pollinator interactions and on future decisions in restoration and conservation planning / A conservação e restauração dos polinizadores são essenciais para a manutenção das populações vegetais nas paisagens fragmentadas, pois eles proporcionam diversidade genética entre os indivíduos espacialmente isolados. Dado que se espera que as populações nas florestas remanescentes e restauradas se perpetuem com o passar dos anos, os programas de restauração devem ser planejados também considerando alcançar este objetivo. Neste trabalho avaliamos as interações planta-polinizador em florestas tropicais em restauração, objetivando estabelecer primeiro, os requerimentos de polinização nestas comunidades e segundo, se os requerimentos de habitat dos polinizadores estão sendo satisfeitos e as interações entre plantas e polinizadores estão se recuperando através das práticas de restauração. O trabalho compreende dois capítulos: No primeiro (\"Os sistemas de polinização de espécies arbóreas estão se recuperando por meio da restauração de florestas tropicais?\") realizamos uma revisão exaustiva na literatura sobre a biologia da polinização das espécies de árvores em florestas primárias, plantios de restauração e florestas naturalmente regeneradas, para depois comparar e identificar os padrões na diversidade funcional e nas assembléias de modos de polinização. No segundo capítulo (\"Respostas e efeitos funcionais das comunidades de abelhas em florestas tropicais restauradas\") coletamos abelhas (i.e. os principais polinizadores) e identificamos os grãos de pólen aderidos no seu corpo, em florestas primárias, plantios de restauração, áreas herbáceas degradadas e cultivos de cana-de-açúcar; depois analisamos e comparamos a diversidade funcional das comunidades de abelhas e seus recursos florais, a estrutura das redes de interação e também em resposta ao isolamento do habitat. Encontramos que diferentes práticas de restauração geraram maiores mudanças nas proporções de vários modos de polinização, em lugares submetidos a atividades de restauração ativa do que nas florestas regeneradas naturalmente. Especificamente no caso das abelhas, encontramos que a demanda pela sua função como polinizadores nos plantios de restauração era ainda maior do que nas florestas primárias, pois muitas espécies de árvores polinizadas por abelhas estavam sendo preferivelmente plantadas graças a sua maior habilidade como colonizadoras, ou devido à outras funções e serviços ecossistêmicos que elas provem. Observamos que as abelhas estavam se beneficiando dessa super-representação de recursos florais, dado que várias espécies visitaram mais freqüentemente as árvores presentes nos plantios de restauração do que em outras áreas. Apesar dessa preferência, a abundância de indivíduos e a diversidade funcional nas comunidades de abelhas ainda não estavam totalmente recuperadas nas áreas em restauração, provavelmente porque alguns dos seus requerimentos de habitat estão ainda pouco fornecidos (e.g. recursos de nidificação). Mesmo que a diversidade funcional nas comunidades de abelhas tenha sido alta de maneira geral, somente uma pequena parte dela, que também foi a mais vulnerável (i.e. abelhas de maior porte que nidificam por cima do solo, tem diferentes níveis de sociabilidade e são polilécticas), foi a principal encarregada do transporte de pólen das plantas mais importantes das florestas primárias e restauradas (i.e. plantas lenhosas, nativas, de successão inicial e com diferentes modos de polinização). Ao longo deste trabalho analisamos e discutimos as implicações destes resultados para a recuperação das interações planta-polinizador e nas futuras decisões no planejamento da restauração e conservação ecológica

Macroecology is the study of relationships between organisms and the environment at large spatial and temporal scales. This field of research examines patterns in species abundance, distribution and diversity. Understanding patterns in species distribution and richness can contribute significantly to our knowledge of community assembly and macroecological patterns, as well as to the effective conservation of threatened species and habitats. Although there have been a plethora of studies on birds in India over the years, there is a critical need to accurately delineate species distributions and understand patterns of richness. The focus of this study was to understand the factors (abiotic and biotic) that influence the distribution and composition of bird species in the Western Ghats, as well as to explore patterns in their geographic range sizes. The objectives of this study were addressed at the scale of the entire Western Ghats using a combination of field surveys, secondary data collection and species distribution modeling. The specific approaches to address these questions and the findings are outlined below. Chapter 2: Bird species in the Western Ghats – Patterns in composition and richness Fine-scale data on species presence and abundance are essential for exploring patterns in species distribution and richness. Despite the fact that birds have been extensively studied in the Western Ghats, systematic data collection and compilation of information over the entire mountain range has not been carried out, especially for the purpose of testing macroecological questions. This chapter describes patterns in bird species presence, abundance, composition and richness within the Western Ghats. The study area, site selection protocol and the sampling technique have also been described in detail. This dataset establishes a baseline of information about birds in the Western Ghats and subsets of this larger dataset will be used to address various questions in the following chapters. Chapter 3: Predicting bird species distribution in the Western Ghats Detailed knowledge of species’ ecological and geographical distributions is fundamental for conservation, as well as for understanding ecological and evolutionary determinants of spatial patterns of biodiversity. However, occurrence data for a vast majority of species are sparse, resulting in information about species distributions that is inadequate for many purposes. Species distribution models attempt to provide detailed predictions of distributions by relating presence or abundance of species to environmental predictors. In this chapter, we describe the usage of Maxent, a species distribution modelling technique based on presence-only data, to predict the distributions of bird species within the Western Ghats. For this purpose, we put together primary locations of bird species presence along with a published dataset. Using a number of important environmental layers, predicted species distribution maps were derived for 98 bird species, including 13 endemics, in the Western Ghats. Additionally, we calculated predicted range sizes for each of these species and obtained percentage contributions of important environmental predictors to each species’ distribution. This is the first study to develop species distribution models for bird species within the Western Ghats. Chapter 4: Patterns of range size among bird species Understanding large-scale patterns of variation in species geographic range size is fundamental to questions in macroecology and conservation biology. In general, range is believed to be influenced by a combination of environmental factors, evolutionary history and biotic interactions, mediated by species specific traits. These patterns need to be examined even for well-studied taxa like birds, especially within biodiversity hotspots faced by persistent degradation due to anthropogenic activities such as the Western Ghats. In this chapter, we use a dataset of 98 bird species within the Western Ghats to examine trends in range sizes, measured as latitudinal extent of occurrence and predicted range size from species distribution models. We show a significant relationship between latitude and range size for these bird species, supporting Rapoport’s rule. As far as we know, this relationship has never been tested at such low latitudes for birds. We also find that species traits such as body size, mean abundance and diet do not seem to show any discernable effect on patterns of range size. Additionally, we found that widely-used bird species range maps (in this case, from BirdLife International) are inaccurate representations of species ranges in comparison to the predicted species distribution maps that were derived in the previous chapter. We quantitatively demonstrated that these expert-drawn maps need to re-evaluated, especially since they are used to make conservation decisions. This is the first study to quantify species range sizes of birds within the Western Ghats and assess such range maps that are used to determine conservation status of species. Chapter 5: Environmental predictors of bird species distribution One of the major goals in ecology is to understand patterns and processes that determine species diversity. The drivers of global species richness gradients have been studied, especially in the case of birds, in terms of contemporary and historical factors. Such broad scale processes may not always reflect the processes affecting richness and distribution at smaller scales. Therefore, understanding the factors that influence individual species distributions is the first step towards this larger goal. In this chapter, we examined the environmental predictors that contributed to the predicted distribution of bird species observed in the Western Ghats, using the variable importance contribution values derived in Chapter 3. We found that a large proportion of the 98 bird species studied were influenced by normalized differential vegetation index, annual precipitation and elevation. The predictors did not differ among birds of different diet guilds and body size classes. Using Prinicipal components analysis, we observed that all 98 bird species are spread out across the environmental ordination space depicted by the PC axes 1 and 2. These axes are governed by measures of habitat heterogeneity and water-energy related variables, consistent with other tropical studies. The insectivorous guild seemed to occupy a variety of environmental niches across this space and other guilds seemed to be nested within the insectivorous guild. Similarly, larger sized birds were spread across the entire environmental ordination space, with species of smaller sizes nested within. This is the first step in trying to understand environmental predictors acting on birds in the Western Ghats. Further detailed studies need to be carried out to come to definite conclusions. Chapter 6: Relative roles of floristics and vegetation structure on bird species composition On the basis of the hierarchical model of habitat selection, it is known that birds select suitable habitats based on vegetation structure (physiognomy) at coarse biogeographic scales, and plant species composition (floristics) at more local scales. This chapter examines the relative influence of tree species composition and vegetation structure on bird species composition in the Western Ghats. These relationships were specifically assessed across the entire Western Ghats, within regions of the Western Ghats as well as within specific forest types. We found that floristics had a strong association with bird species composition across the Western Ghats and within evergreen and mixed deciduous habitat types. This association seems to be independent of the structural variation in the region. There was a decrease in association strength from the southern to the northern Western Ghats, in terms of both floristics and structure. We did not find an association between vegetation structure and insectivore composition, whereas phytophage composition did show a stronger association with floristics than structure. This is the first study at the scale of the entire Western Ghats to test the relative roles of floristics and vegetation structure. Taken as a whole, this dissertation examines large-scale macroecological questions regarding species distribution, range size and patterns of composition using primary data at the scale of the Western Ghats. The findings of this study have established a foundation that will help further our understanding of species distribution and richness in the Western Ghats, and aid in the decision making for conservation strategies in the future.