Infectious Disease Ecology of Wild Birds

Description

Birds are the most diverse group of land vertebrates and have evolved to exploit almost every terrestrial niche on earth. They also serve as a natural reservoir for an array of different pathogens that pose serious health risks to human and domestic animal populations, including West Nile virus, highly pathogenic avian influenza viruses, Newcastle Disease virus, and numerous enteric pathogens. Avian diseases are also critically important to the conservation of endemic bird species in many places around the world. This accessible textbook focuses on the dynamics of infectious diseases for wild avian hosts across every level of ecological hierarchy, from the way pathogens interact with the physiology and behavior of individual hosts, the evolutionary and ecological dynamics of the host-parasite interactions occurring within populations, up to the complex biotic and abiotic interactions occurring within biological communities and ecosystems. Parasite-bird interactions are also increasingly occurring in rapidly changing global environments - thus, their ecology is also changing - and this shapes the complex ways by which parasites influence the inter-connected health of birds, humans, and shared ecosystems. Given the key role of birds in ecological communities more broadly, and as the primary host to so many zoonotic pathogens, an understanding of the ecological and evolutionary principles underlying the maintenance, amplification, transmission, and dispersal of these infectious agents is crucial to understanding how to mitigate the negative global impacts of the ever-increasing number of emerging infectious diseases. Although the topics and principles discussed in this book relate to birds, they have a far wider relevance and can also be applied to non-avian, wildlife host-pathogen systems. The COVID-19 pandemic has shown that understanding of disease ecology in wild animal populations is paramount to global health. Infectious Disease Ecology of Wild Birds is suitable for both senior undergraduate and graduate students taking courses in avian disease ecology, ecoimmunology, ecology, and conservation. It will also appeal to the many professional parasitologists, ecoimmunologists, ornithologists, behavioural ecologists, conservation biologists, and wildlife biologists requiring a concise overview of the topic. Cover Infectious Disease Ecology of Wild Birds Copyright Foreword References Preface Contents List of Contributors Chapter 1: A Bird’s Eye View of Avian Disease Ecology Literature cited Chapter 2: The Nature of Host–Pathogen Interactions 2.1 Introduction 2.2 Causation of disease 2.2.1 Hosts 2.2.2 Pathogens and parasites 2.2.2.1 Microparasites and macroparasites 2.2.2.2 Routes of transmission 2.2.2.3 Virulence and pathogenicity 2.2.3 Vectors 2.2.4 Environment 2.3 Host–parasite interaction: infection timeline 2.3.1 Progression of host’s disease state 2.3.2 Progression of host’s infectious state 2.3.3 Linking states of infection to compartmental models 2.3.4 Withinhost dynamics: pathogenesis 2.3.4.1 Exposure and colonization 2.3.4.2 Attachment and invasion 2.3.4.3 Pathogen replication and activation of host immune response 2.3.4.4 Resistance and tolerance 2.3.4.5 Pathogen shedding/exit 2.4 Developing pathogenspecific immunity 2.4.1 Maternal transfer of antibodies 2.5 Detecting and quantifying a host’s infection status 2.5.1 Visual detection 2.5.2 Microscopy 2.5.3 Molecular detection 2.5.4 Experimental manipulations of infection status 2.5.5 Immunological assays 2.5.5.1 Antibody persistence 2.6 Populationlevel disease dynamics 2.7 Summary Literature cited Chapter 3: Ecoimmunology 3.1 Introduction 3.2 Overview of the avian immune system 3.2.1 The innate immune system 3.2.2 The adaptive immune system 3.2.3 An integrated response to infection 3.3 Drivers of variation in immune defense 3.3.1 Sex 3.3.2 Age 3.3.3 Life history stage 3.3.4 Environmental stressors and physiological stress responses 3.3.4.1 Environmental stressors: food availability 3.3.4.2 Environmental stressors: anthropogenic factors 3.3.4.3 Physiological stressors: oxidative stress 3.3.4.4 Physiological stressors: endocrinemediated stress response 3.3.4.5 Relationships among individual and environmental factors and immune responses 3.4 Quantifying variation in immune defenses 3.5 Bridging the first gap: do immune phenotypes predict infection status or host fitness? 3.6 Bridging the second gap: do withinhost measures inform populationlevel transmission dynamics? 3.7 Conclusions Literature cited Chapter 4: Behavior Shapes Infectious Disease Dynamics in Birds 4.1 Conceptual overview: the intersection of behavior and disease ecology 4.2 Behaviors important to parasite exposure, resistance, and spread 4.2.1 Antiparasite behaviors 4.2.1.1 Preening 4.2.1.2 Deterrence of aerial parasites 4.2.1.3 Nest ‘selfmedication’ 4.2.2 Sickness behaviors 4.2.2.1 Manifestations and putative function of sickness behaviors in birds 4.2.2.2 Contextspecific sickness behaviors 4.2.2.3 Sickness behaviors and transmission 4.2.3 Foraging and movement behaviors 4.2.3.1 Foraging behavior and exposure risk 4.2.3.2 Migration and disease dynamics 4.2.3.3 Effects of disease on movement and foraging 4.2.4 Personality 4.2.4.1 Personality and exposure 4.2.4.2 Personality and resistance 4.2.4.3 Personality and infection spread 4.2.5 Mate choice and sexual selection 4.2.5.1 Reproductive strategies and exposure 4.2.5.2 Reproductive strategies and resistance 4.2.5.3 Reproductive strategies and pathogen spread 4.2.6 Social behavior 4.2.6.1 Transmission routes and social behavior 4.2.6.2 Dominance behavior 4.2.6.3 Collective defense behaviors 4.3 Synthesis and future directions Literature cited Chapter 5: Host–Pathogen Evolution and Coevolution in Avian Systems 5.1 Introduction 5.2 Evolutionary responses of avian hosts to their pathogens 5.2.1 Preventing infection 5.2.2 Reducing the costs of infection 5.2.2.1 Life history changes 5.2.2.2 Resistance and tolerance Evidence from avian immune genes Evidence of phenotypic evolution 5.3 Evolutionary responses of pathogens to their avian hosts 5.3.1 Molecular evolution 5.3.1.1 West Nile virus (WNV) 5.3.2 Adaptive phenotypic responses of pathogens 5.3.2.1 Empirical evidence in birds 5.4 Coevolution of avian hosts and their pathogens 5.4.1 Macroevolutionary studies 5.4.2 Microevolutionary studies 5.4.2.1 Spatial adaptation experiments 5.4.2.2 Temporal adaptation experiments 5.5 Conclusions and implications Literature cited Chapter 6: Fitness Effects of Parasite Infection in Birds 6.1 Introduction 6.2 Effects of parasites on host survival 6.2.1 What is needed to show parasitemediated differences in survival? 6.2.2 What evidence is there that parasites influence individual survival in birds? 6.2.2.1 Parasite characteristics that impact effects on host survival 6.2.2.2 Host characteristics that impact parasite effects on survival 6.3 Effect of parasites on reproductive success 6.3.1 Breeding phenology, pairing success, and parentage 6.3.2 Clutch size 6.3.3 Hatching success and/or brood size 6.3.4 Fledging success 6.3.5 Parental provisioning rates, parental care, and transgenerational effects 6.3.6 Apparent positive effects of parasite infection on fecundity 6.4 Contextdependence of fitness effects 6.5 Summary Literature cited Chapter 7: Wild Bird Populations in the Face of Disease 7.1 Introduction 7.2 Tools for assessing effects of parasites on avian populations 7.2.1 Describing infection status in avian populations 7.2.1.1 Prevalence 7.2.1.2 Estimating host population size 7.2.1.3 Mark- recapture methods 7.2.1.4 Occupancy methods to estimate prevalence 7.2.2 Parasite population size 7.2.2.1 Parasite load 7.2.2.2 Parasite aggregation 7.2.3 Epidemiological modeling 7.2.3.1 Compartmental models 7.2.3.2 Agent- and individual- based models 7.2.3.3 Social network analysis and network models 7.2.4 Additional tools and resources 7.3 Effects of parasites and pathogens on avian host populations 7.3.1 Parasites and declines in avian host population size 7.3.1.1 Case study: Trichomonas gallinae 7.3.1.2 Case study: West Nile virus 7.3.2 Parasites and avian host population growth 7.3.2.1 Case study—avian blood parasites 7.3.3 Host population regulation and fluctuation linked to parasites 7.3.3.1 Case study—Mycoplasma gallisepticum 7.3.3.2 Case study—Trichostrongylus tenuis 7.3.4 Local extinctions of host populations 7.4 Lessons learned Literature cited Chapter 8: CommunityLevel Interactions and Disease Dynamics 8.1 Introduction 8.2 Community structure and function 8.2.1 Community ecology and the place of birds 8.2.2 Parasites in communities 8.3 Community diversity and parasite/ pathogen circulation 8.3.1 Interspecific host heterogeneity 8.3.2 Changing biodiversity 8.3.3 Parasite communities within avian communities 8.3.3.1 Parasite infracommunity 8.3.3.2 Parasite component community 8.3.3.3 Parasite metacommunity (or supracommunity) 8.3.4 Modified communities 8.4 An example of Lyme borreliosis in seabird communities 8.4.1 The biological system 8.4.1.1 Seabird communities 8.4.1.2 Ticks and the circulation of Lyme borreliosiscausing agents 8.4.2 Population structure of Ixodes uriae within and among seabird communities 8.4.3 Understanding spatial patterns of Lyme borreliosis within and among avian communities 8.4.3.1 Within and among seabird colonies 8.4.3.2 Linking marine and terrestrial enzootic cycles 8.5 Summary and future directions Literature cited Chapter 9: Land Use Change and Avian Disease Dynamics 9.1 Introduction 9.1.1 Major drivers of land use change 9.2 Key changes associated with land use and influences on disease dynamics 9.2.1 Habitat loss, degradation, and fragmentation 9.2.2 Chemical pollutants (toxicants) 9.2.2.1 Heavy metals 9.2.2.2 Persistent organic pollutants 9.2.2.3 Other chemical pollutants 9.2.3 Light and noise pollution 9.2.4 Anthropogenic resources 9.2.4.1 Supplemental feeding 9.2.4.2 Unintentional anthropogenic resources 9.3 Overall consequences of land use change for avian parasitism: urbanization as a case study 9.4 Synthesis: need for multidisciplinary approaches Acknowledgments Literature cited Chapter 10: Climate Change and Avian Disease 10.1 Introduction 10.2 Infection consequences of changes in bird distribution and phenology 10.2.1 Latitudinal and elevational shifts in avian breeding ranges 10.2.1.1 Changes in nonbreeding range and movement patterns 10.2.2 Changes in timing of life history events through the annual cycle 10.3 Changes in bird physiology, behavior, and response to infection 10.3.1 Changes in immunity and infection impacts 10.3.2 Changes in behavior 10.4 Effects of climate change on parasites with external transmission stages 10.4.1 Vectorborne and trophically transmitted parasites 10.4.2 Environmentally transmitted pathogens 10.5 Synthesis and future research directions Literature cited Chapter 11: Pathogens from Wild Birds at the Wildlife–Agriculture Interface 11.1 Introduction 11.2 Avian use of agricultural operations 11.2.1 Degree of use of agricultural operations by synanthropic birds 11.2.2 Identification of focal synanthropic avian species 11.3 Host types and pathways for pathogen contamination by birds 11.3.1 Host types 11.3.2 Types of pathways for contamination 11.3.3 Spillover versus spillback 11.4 Pathogen prevalence and transmission in wild birds 11.4.1 Major pathogens of concern 11.4.1.1 Bacterial pathogens 11.4.1.2 Newcastle Disease virus 11.4.1.3 Avian influenza viruses 11.5 Contamination potential of agricultural operations by birds 11.6 Longdistance movements and pathogen introductions 11.7 Future directions Literature cited Chapter 12: Pathogen Transmission at the Expanding Bird–Human Interface 12.1 Introduction 12.2 Examples of zoonoses at the intersection of wild bird, domestic bird, and human populations 12.2.1 Human surveillance for avian zoonoses—a call for more 12.3 Ecological and evolutionary factors important for zoonotic emergence at the wild bird–human interface 12.4 Birds as vehicles for the movement of arthropod vectors and pathogens of human health concern 12.5 Reverse zoonoses (anthroponoses): examples of pathogen transmission from humans to birds 12.6 Parasite interactions in birds—implications for human health 12.7 Management strategies to minimize avian zoonoses 12.8 Summary Literature cited Chapter 13: A Flight Path Forward for Avian Infectious Disease Ecology 13.1 Introduction 13.2 A flight path for avian disease ecology that crosses scales and disciplines 13.3 Leveraging existing strengths to promote innovation 13.4 A flight path forward for avian infectious disease ecology, management, and conservation 13.5 Conclusions Literature cited Index