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This chapter considers aspects of the maternal parent, other than the tissues immediately around the seed, which contribute to the distances dispersed by plant propagules. It shows how plant phenotype, the abiotic environment, competition, and herbivory all help to determine where the trajectories of propagules begin. Plant phenology dictates when the force required separating the propagule from its parent is at a minimum, and therefore when the trajectory is likely to begin. This can be critical for the survival of animal vectors as well as for movement of seeds contained in fruits. In some cases, the parent provides an additional force to launch the propagule away from its parent.

Several solitary bee species in the genus Osmia have been studied as potential pollinators of fruit trees and other early-blooming crops. Methods to manage large populations in agro-ecosystems have been developed for at least three species. This chapter reviews current knowledge on the life cycle of Osmia and emphasizes the need to establish a solid ecophysiological basis to develop adequate rearing methods for these species. Two phenological events — the timing of adult diapause in the autumn, and the timing of emergence in the spring — require particular attention when managing Osmia populations. The timing of adult diapause is critical because pre-wintering temperatures have a profound effect on fat body depletion, winter survival, and vigor at emergence. Timing of emergence and its synchronization with bloom of the target crop is important to maximize pollination and production of bee progeny. Both events can be adjusted with proper temperature management.

Migration by Odonata may illuminate patterns and evolution of insect migration in general. As aquatic/aerial carnivores dragonflies differ from most migratory insects, and because they are large and diurnal, observational techniques are available that are impossible in most other insects. Geographic analysis of genetic structure and stable and radiogenic isotope composition and use of newly developed radio-tracking techniques has been applied to migration in the North American dragonfly, Anax junius. Southbound migrants move up to 2,800 km. Developmental phenology suggests early (‘resident’) and late (‘migrant’) cohorts at most sites, but these groups appear genetically identical, and the species is essentially panmictic in eastern North America. Apparently environmental cues and physiological responses to photoperiod and temperature engender migratory behaviour. Successful radio-tracking of individual A. junius has revealed alternating periods of migration and energy replenishment, and responses to wind and temperature similar to avian migration.

Although grass- and herb-dominated ecosystems may be easier to sample for aboveground primary production than most others, a variety of challenges for standardizing approaches in different settings and circumstances must be overcome. This chapter describes the most common harvest approaches for grassland production measurement and a suite of site-specific criteria that affect the choice of approach (e.g., grazing, decomposition, phenology). Errors leading to either underestimation or overestimation are examined, and a case study describing approaches for evaluating sample adequacy is provided.

This chapter first considers the process of flowering phenology and pollination, and techniques for measuring fruit production, dispersal, and predation. It then presents methods for analysing the mating systems of plants and the genetic structure of populations. Topics covered include pollination ecology, flowering and fruiting phenology, seed ecology, and assessment of genetic variation.

This chapter looks at examples illustrating patterns in phenological responses to observed and experimental climate change. The most commonly observed phenological response to recent climate change is an advance in the timing of early life history events such as migration, plant emergence or flowering, amphibian breeding, or egg-laying dates in birds. Patterns in satellite-derived images of primary productivity suggest a lengthening of the plant-growing season in recent decades, whereas data on plant phenological dynamics from studies conducted at plot and sublandscape scales indicate shortened phenophases, or phenological events, in response to warming. This contrast may be resolved by recognizing the difference between phenology in the context of individual life history strategies of disparate species and landscape-scale patterns of phenology, and by recognizing the difference between local, species-specific phenological dynamics and those occurring at the landscape scale.

This chapter examines the factors that affect the timing and patterning of flowering, as well as the effects of different flowering patterns on pollination outcomes. Plants should flower in ways that maximize their own reproductive success. The “flowering pattern” is a composite of the timing and frequency of individual flowers opening, and also of floral longevity. These phenological factors vary between and within species. Flowering phenology can influence the plant’s manipulation of its visitors in ways that should increase either or both of pollen transfer and pollen receipt. The chapter first considers the frequency of flowering and the shape of the flowering period before discussing flower longevity and flowering period. It also explores the question of how big a flower should be, how many flowers a plant should have at any one time, what determines the phenological parameters for a particular plant species, and where the flowers should be placed.

The various forms of African savannah vegetation are an expression of the interactions of climate, soils, herbivores, fire, and human activities. This chapter examines each of these causes. A brief description of the common grasses and trees is given, along with a consideration of aspects of their phenology. One geographical area is examined in more detail — the Serengeti grassland/woodland savannah of northern Tanzania. The effects of soil and particularly rainfall upon green biomass, and grass and tree species composition are examined.

It has long been assumed that Sumatran forests are of higher quality for orangutans than Bornean forests, and that this is both the proximate and ultimate cause of many of the differences in socio-ecology between the two orangutan species. Yet this hypothesis has remained untested. This chapter presents data on the phenology and floristics of eight Bornean and three Sumatran forest sites where orangutans have been studied to examine the effects of floristic composition, habitat productivity, and seasonality on orangutan population density. The alternative hypotheses that higher orangutan densities in Sumatra are due to overall higher levels of plant productivity, the increased availability of preferred foods, the presence of more fallback foods, or differences in floristic composition between the two islands are tested empirically.

This introductory chapter provides an overview of the role of time in ecology. Generally speaking, time is considered as a conceptual axis, much like space, along which one can measure ecological events and their durations. In ecology, time also allows one to describe, ascribe rates to, and quantify differences in, for example, changes in abundance within and among populations of single species and interacting species. In such a framework, time is a measuring stick and half of the stage—the complementary half of which is space—upon which ecology plays out. Over the ensuing chapters, an argument will be constructed for the development of a framework for a novel way of thinking about time in ecology, using the study of phenology as an exemplar for doing so.

This chapter begins by distinguishing phenology from seasonality. Phenology is defined as the study of the occurrence of phenomena in relation to time. In contrast, seasonality refers to temporal variation in abiotic environmental conditions. The chapter then presents the central findings of four major reviews of phenological change over the past several decades. This overview shows that, first, in general, recent phenological trends in plants and animals tend overwhelmingly to be negative—that is, species across a diverse array of taxa appear to have tended toward earlier timing of springtime activity in concert with recent climatic warming. Second, however, it demonstrates that there has not been a universal tendency toward earlier timing of springtime phenological events with warming. Lastly, the overview reveals that there is, indeed, some evidence for a latitudinal trend in rates of phenological advance. The chapter also looks at phenological dynamics across taxa, latitude, and time.

This chapter studies how the concept of phenological community relates to the utilization of time by species that co-occur in the local assemblage. It also examines the consequences for phenological community dynamics of differential use of time by co-occurring species. Indeed, a main point of emphasis in this chapter is the dynamic nature of the community in a phenological context. The allocation of time by the individual organism to phenophases within its annual cycle of growth, maintenance, and reproduction determines patterns of interactions in time among species co-occurring in the local assemblage. In the context of phenology, the local community is characterized by a capacity for pronounced variability on both short-term temporal scales (over days) and on longer-term temporal scales (from year to year).

This chapter examines the role of time in vertical species interactions. Vertically structured communities are those shaped primarily by interactions among organisms at different trophic levels. Hence, these comprise exploitation interactions typified by predator—prey interactions, pathogen—host interactions, herbivore—plant interactions, and consumer—resource interactions in general. In such interactions, consumer success—in terms of growth, survival, and reproduction—depends upon synchronization of consumer phenology with resource phenology. In contrast, the success of resource species may depend upon minimizing synchronization of their phenology with that of species by which they are consumed. In mutualistic interactions, however, in which both species function as a resource for one another, the success of both species depends upon phenological overlap. The chapter then explores some examples of the role of time in the phenology of all three types of players in vertical species interactions—resource species, consumer species, and mutualistic species.

Conservation biologists and natural resource managers often require detailed, accurate information on natural resources or biodiversity elements such as species, landscapes, and ecosystems. Their patterns of occurrence and their responses to environmental disturbance or change are dynamic over space and time and may be mediated by complex ecological processes. In most cases, our ability to directly measure or comprehensively map biodiversity elements is limited by human or financial resources, and logistical challenges such as difficulties in accessing terrain or short field seasons. In other situations, we might want to make quantitative inferences about, say, the kinds of environments that are most suitable for the persistence of an endangered species, or the influence of landscape modification on its highest-quality habitat. In these cases, developing models that explain and predict the patterns of biodiversity elements can help provide guidance at scales and resolutions that are not available through direct measurement. For example, Goetz et al. (2007) employed lidar data to predict the bird species richness across a 5,315 ha temperate forest reserve, the Patuxent National Wildlife Refuge (PWNR) in the eastern United States. In this study, Goetz et al. derived and mapped several measures of forest canopy structure, including canopy height, and three descriptors of the vertical distribution of canopy elements. In addition to lidar, they also used optical remotely sensed data from two dates of Landsat ETM+ to derive NDVI during the growing season and the difference between the NDVI of leaf-on and leaf-off conditions (growing season versus winter). Testing three different quantitative statistical models (stepwise multiple linear regression, generalized additive models, and regression trees) to predict bird species richness, the authors used field survey data on the birds of the PWNR that were collected at a series of fixed points across the reserve as the training data for the response variable (bird species richness). To calibrate the model, they combined the habitat descriptors with the survey data, usually reserving 25 percent of the survey data to validate each model’s results.

Animals face many challenges during migration, including ‘where to go’ and ‘when to go’, for which migrants derive relevant information from proximate external (environmental) and internal (physiological) cues. This chapter synthesises the cues and decision rules in the phases of migration for the major migratory taxa. It makes some preliminary generalisations concerning the similarities and differences of the cues used across taxa and phases of migration. For instance, preparations for migration involve entrainment to time of the year and, consequently, photoperiod appears to be a ubiquitous cue. Furthermore, preparations often include changes in the body, and once these are accomplished, an internal cue indicates readiness to depart. The chapter concludes that much could be learned by overcoming taxonomic borders, identifying similarities and differences in the various migration types, and integrating theoretical and empirical efforts.

This chapter examines four citizen science projects launched by the Cornell Lab of Ornithology and other organizations. The projects have been designed with unique scientific goals, educational objectives, and intended audiences, and carried out at varying scales and levels of complexity. Two of the projects are Project FeederWatch and Neighborhood Nestwatch, which focus on birds, while the other two, Project BudBurst and Monarch Larva Monitoring Project, deal with plant phenology and insect ecology, respectively. This chapter provides an overview of project design, participant interaction, training and educational resources, data collection and validation, impacts, and sustainability. It also discusses some of the lessons that can be drawn from each initiative.

This chapter focuses on plant reproduction in the seasonal dry forest of Costa Rica. It discusses flowering phenology and pollination systems in the dry forest and compares the diversity with that of other tropical forests. It also discusses future studies and applications to conserve pollinator populations.

This chapter describes field-study research on the habitats of treeshrews in Malaysia. About 20 percent of the mammal species of Borneo are endemic to it, including seven of its ten species of treeshrews. All of these treeshrews dwell in the tropical rainforests, and the large geographic extent and elevational variation of Borneo may have provided a field for speciation and persistence for this family poorly represented elsewhere. The chapter describes the fruiting phenology, the history of disturbance, and the biogeographic history of treeshrew habitats in Malaysia.