Bird migration is not only a fascinating phenomenon per se, but also represents an example of a highly adapted phenotype that is regulated by fine-tuned behavioural, sensory and genetics mechanisms. To a large extent, these mechanisms still remain unknown. There is evidence that naïve avian migrants follow a genetic programme to find their way between breeding and wintering grounds crossing 100’s or even 1000’s km. Birds are well-known to be navigators capable of reaching remote destinations with high accuracy using a variety of natural cues such as the sun, stars, the Earth’s magnetic field, odours and landmarks. Many questions in this field, however, remain open. For example, what is the genetic architecture that determines in which direction(s) and how long a migratory bird should migrate to successfully reach its destinations? Which sensory systems are involved in avian navigation and compass orientation? How is information from different orientation cues integrated? How can birds perform True Navigation, i.e. return to a known destination after displacement to a completely unknown location without relying on familiar surroundings and cues that emanate from the destination? In recent years, the body of studies in this field has increased rapidly. At the same time, experimental data usually get published years after they have been collected. The objective of this symposium is to bring together experts from the field of migration genetics and orientation to give an overview about the latest progress in both fields and motivate research synergies moving forward.
20. Evolution and ecology of avian nectarivory
Alejandro Rico-Guevara, Anton Pauw
Remarkable cases of convergent evolution occur in nectar-feeding birds that have specialized to exploit the sugar-rich rewards of some plants, and in turn, plants have specialized in bird-pollination mutualisms. A recent survey by one of us and preliminary morphological data, identify 20+ independent origins of nectarivory within birds, in contrast to other recent reviews, the exact number depending on the criteria for “specialized nectarivore”. Addressing and bringing together a diversity of perspectives is crucial to reach agreements in science, and our aim with this symposium is to capitalize on the momentum of renewed interest on avian nectarivory, including adaptations for exploitative and interference competition. Researchers are using modern tools to study convergence in nectarivorous birds in areas such as morphology (e.g. μCT scanning), biomechanics (e.g. high-speed cameras), sweetness perception (e.g. transgenics), and developmental/genetic underpinnings (e.g. whole-genome sequencing). The evolution of birds solving similar challenges to feed on nectar has a rich history, and since these groups are converging on more than diet (e.g. iridescent colorations, bill traits unrelated to feeding), the inferences and discussions on this symposium would be relevant for other scenarios of evolutionary convergence in birds, exemplifying how the “cross-pollination” from multiple fields can shed light on common biological questions.
21. Hormones, metabolism, and performance: how endocrine mediated traits affect fitness
Ignacio Moore, Stefania Casagrande
Understanding how endocrine-mediated traits evolve to support animal life is a major goal of organismal biology, giving investigators an opportunity to integrate concepts about molecular mechanisms, metabolic activity, performance, and ultimately fitness. Birds have long been a focus of research on these topics, because of their diverse natural history strategies including adaptations to parental care systems, breeding schedules, migratory behavior, courtship tactics, and responsiveness to challenges across different environments. In the last decade, studies that leverage genomic, endocrine and metabolic techniques have fundamentally reshaped our ability to understand the evolution of this variation among the avian world. However, these studies rarely integrate among these techniques or scale up to determine an effect on performance measures that otherwise shape fitness.
We will draw attention to the need to integrate measures of hormone activity with specific metabolic traits to broaden our comprehension of how hormones regulate avian life histories and behavioral strategies. Specifically with this symposium, we will look to highlight a number of ways that established and emerging ornithologists are conducting such research through combined genomic, endocrine, and metabolic approaches. Our proposed speakers will represent the diversity of the field, from career stage to techniques employed, and behaviors studied. However, all are based on the same theme of developing an integrated understanding linking hormonal action, metabolic activity, trade-offs, and genetics to the evolution of life history and social strategy.
22. Effects of sea-level rise on birds
Chris Elphick, Martijn van de Pol
This symposium will bring together researchers working on the effects of sea level rise on birds in different coastal ecosystems to produce a comprehensive synthesis of what is known about the topic. Recent sea-level rise is already threatening various bird species with extinction, and others with population decline. Future projections suggest that these effects will increase considerably this century. Research has been conducted on birds that use tidal marshes, beaches, mudflats, oceanic atolls, and coastal forests. This work has included detailed studies of vital rates and population viability, large-scale projections of habitat conversion and loss, and applied investigations into mitigation and habitat restoration strategies. To date, however, most research has been conducted with little synthesis across taxonomic, habitat, or regional boundaries.
Keynote presentations will:
(1) provide a global overview of the challenges that birds face from sea-level rise. The talk will summarize the most current information on patterns of sea-level rise, and future projections; which species have been studied, in what systems, and where; the variety of ways in which species are threatened; the types of solutions that have been proposed or implemented; and priorities for future research.
(2) describe the modelling approaches taken to address the effects of sea-level rise on birds; the modelling challenges involved; how models are informing our understanding of avian responses; and priorities for future model development.
Additional talks will provide more detailed discussion of the effects of birds in diverse coastal ecosystems.
23. Energetics of avian movement in a changing world
Kyle Elliott, Ivan Maggini
Birds are the most versatile of the vertebrate classes, moving in all three media, with some species flying thousands of kilometers in very different environments and climatic zones. Such movements, however, entail very high energy costs, and flying birds consequently have the brightest ‘fires of life’–the highest mass-specific metabolic rates of any animal–leaving them vulnerable to overheating while opening foraging opportunities in energy-rich, warmer world. Thus, there is a crucial need to understand how abiotic features (temperature, humidity, irradiation, etc.) will impact energetic performance, and eventually the ecology, of wild birds. Indeed, making predictions about the impact of climate change on different species involves modelling the physiological response of individuals/species to different environmental variables and combine these with predicted climate scenarios. This symposium will provide an overview of the energetic mechanisms underlying responses to climate change, at rest and in flight, and their links to ecology and range shifts. We will focus on the metabolic response to increasing temperatures and extreme weather events, and how physiological constraints might limit bird activity, especially flight, eventually limiting distribution. Avian energetics has given us classic ideas (i.e. ‘the prudent parent’; ‘energy ceiling’) that have resonated beyond physiology, and our symposium will bring a 21st Century update to those ideas in the context of climate change. We expect a range of talks, covering a range of techniques (respirometry, heart rate, doubly-labelled water, thermal imaging, accelerometry), on many taxa (seabirds, raptors, passerines) from the Arctic to the Tropics.
24. Urban ecophysiology: the role of plasticity and evolution
Caroline Isaksson, Fran Bonier
Urban environments are rapidly increasing worldwide, and natural habitats for birds are thereby decreasing. Many bird species have colonised urban habitats, however, to live in this novel environment birds often need to adjust physiologically and/or behaviourally. The novel factors linked to urban habitat that birds need to cope with include increased air pollution, noise, artificial night at light, and ambient temperatures as well as a changed diet (often of higher abundance but of lower quality), different pathogens, competitors, and predators. In this symposium, we aim to focus on the physiological adjustments and adaptations found in birds living in urbanised environments. Key questions we will address include: Are some of these physiological adjustments similar across species? Are these responses driven by acclimation or genetic adaptation to the urban habitat? Do some physiological traits represent “pre-adaptations” to urban environments? In addition, we will discuss the use, misuse, and interpretation of physiological biomarkers in an urban context, and where to go next.
25. Sperm evolution in birds: a perspective from Africa
Taiwo Crossby Omotoriogun, Jan Lifjeld
Sperm cells vary considerably in size and shape across the animal kingdom; so also in birds. There is a strong phylogenetic component in this variation, although the rate of sperm evolution shows much variation among lineages. Sperm evolution can be fueled by sperm competition, i.e. female promiscuity, as species with high extrapair paternity rates tend to have longer sperm and reduced intraspecific sperm length variation. In Passerides songbirds, the coefficient of variation in sperm length among males in a population can serve as a reliable proxy for female promiscuity. Divergence in sperm traits between closely related taxa may also indicate a prezygotic reproductive barrier. The frequency of aberrant or malformed sperm may indicate environmental stress, pollution, inbreeding or disease. Hence, the study of sperm morphology variation within and among species may provide new perspectives on taxonomy and systematics, speciation processes, mating systems and physiological health. Much of the current knowledge of sperm biology in birds has been acquired through studies in the northern temperate zone, while much less is known about tropical species. The symposium seeks to make an overview of current research in avian sperm biology with a special aim to identify gaps in our knowledge and formulate questions for future research. We also hope to attract more interests to the study of sperm biology in birds and create more international collaborations and networking, especially involving researchers working in the tropics.
26. Ethno-ornithology: amplifying the many voices of conservation
Karen Park, John Fanshawe
Ethno-ornithologists study the diverse ways in which people interact with birds, and especially the cultural contexts of such encounters. Since its inclusion as a Round-Table Discussion at the 24th IOCongress™ in Hamburg (2006), and publication of the book that developed out of that (Tidemann, S. & Gosler, A. 2010. Ethno-ornithology: Birds, Indigenous Peoples, Culture and Society), Ethno-ornithology has become a well-defined discipline integrating ornithology, anthropology and linguistics and contributing uniquely to bird and nature conservation. We propose that it has never been more important to listen to local voices, and to follow the lead of local and community initiatives for nurturing biodiversity. The extinction of non-human species, and the global loss of linguistic diversity are recognized as interrelated processes. In 2007, the United Nations Environment Programme (UNEP) declared “…Biodiversity also incorporates human cultural diversity, which can be affected by the same drivers as biodiversity, and which has impacts on the diversity of genes, other species and ecosystems”. Following seminars and symposia at the International Society of Ethnobiology (2016, 2018), the IOCongress™ in Tokyo (2014) and Vancouver (2018), and at the Universities of Oxford and Pittsburgh (2019), a growing network of researchers are collaborating together focused especially around the creation of the Ethno-ornithology World Atlas (EWA) co-created by the University of Oxford (U.K.) and BirdLife International. The proposed symposium encourages people to share working examples of ethno-ornithology research that affirms the significance of local knowledge, language and culture, whilst engendering respect for all biodiversity. The symposium focuses on a number of the key frameworks for ethno-ornithological research relevant to conservation, including the connection, that people have with the land and the powerful role played by birds and language in mediating that sense of connection. We especially encourage co-presentations that include local co-researchers, more than ever possible via online attendance.
27. Contrasting the challenges and opportunities for hornbill conservation biology in Africa and Asia
Lucy Kemp, Aparajita Datta, Jessica Lee
Hornbills (Bucerotidae) are among the few avifaunal families with a comprehensive recent analysis of their genetic phylogenies and taxonomic divisions of their 60+ species (Gonzales 2013). Current taxa indicate an ancestry in sub-Saharan Africa and subsequent colonization of India, Southeast Asia and northern Australasia. This results in different taxonomic and conservation challenges in continental Africa and the more fragmented landmasses habitats of Asia/Australasia. Hence, the IUCN Hornbill Specialist Group operates with African and Asian co-chairpersons. Although these regions have about the same number of species, the reality on the ground in terms of the capacity, resources and, and the regional conservation differences are highlighted by their IUCN Red List status. As of 2020, just three of the African species were listed as Endangered. The remainder are listed as Least Concern which does not correctly reflect their actual status due to paucity of data. None are CITES listed. In contrast, most Asian species are better studied and a greater understanding of conservation needs and classified accordingly, with 4 species listed in Appendix I and 21 species in Appendix II of CITES. Yet the primary threats such as habitat loss and hunting/exploitation for trade are common to both regions and much can be learnt between the regions. The two co-chairs will summarize the progress of global hornbill-related research over the last four years, compare the conservation challenges and opportunities between the two regions and highlight priorities for future research for each region. We also put forward a third ‘region’ – the realm of the existing captive hornbill population that can play a greater role in conservation biology research and rehabilitation of wild populations. We will then welcome three speakers to delve deeper into their learnings, challenges and opportunities with case-studies from their regions and recommendations that will address future research and conservation needs.