The seasonal movements of birds can be divided into two parts: the endurance flight period and the period spent on the ground between two endurance flights. The latter period is commonly termed stopover. Since the total duration of all stopover periods is far longer than the total duration of all endurance flight periods, the stopovers represent a crucial part of the entire seasonal migration. As such, detailed knowledge on the causes of variation in stopover properties (e.g., duration, fueling rates, within- and between-species differences) is essential to understand variation in arrival timing at the migratory destination. That is significant because deviation from the optimal arrival timing can have immediate and delayed fitness consequences on the individual- and population-level, which may lead to population decline and extinction. We argue that we have not yet fully understood “all” the functions of stopover and hence, the causes why a bird would interrupt its endurance migratory flight to stopover.
Our objective is to bring together a diverse array of researchers who study various aspects of stopover, to fill parts of our knowledge gaps in its function. The first keynote will provide a comprehensive overview of the currently known functions of stopover, suggest new ideas about why migratory birds interrupt their endurance flights and provide a general definition of stopover. The second keynote will draw our attention to the importance of physiological recovery during stopover and highlight that this aspect will affect the temporal organization of migration. Other oral presentations will be selected to cover a variety of additional functions of stopover, e.g., sleep, moult, adjusting the timing of migration, behavioural responses to predation danger. Overall, this symposium will summarize novel results and ideas on the function of stopover and by considering the current knowledge will provide a better understanding of the ecological concept of stopover.
38. Living in Extremes: How birds in the Arctic and Antarctica cope with global climate change
Isabella B. R. Scheiber, Noah T. Ashley
Although the Arctic and Antarctic are similar with darkness persisting for half the year and both inhabited by organisms adapted to very extreme conditions, there are fundamental differences between them. So far, the Arctic was thought to be most affected by climate change, and thus has become the hotspot of climate change studies in past decades. Regrettably ice melt in parts of Antarctica has also accelerated recently. This puts the highly specialized biological communities in both regions under severe pressure. Receding sea ice reduces the habitat for species that use ice for feeding, resting or breeding. For migrant birds, which are most sensitive to climate change, this implies that e.g.:
– for feeding they must travel further;
– the prey spectrum might change in response to ocean warming;
– warmer air and water temperatures open the regions for immigrants from mid-latitudes, which causes food competition for native species, and shifting of ranges
– rapid adaptation of various physiological mechanisms to environmental changes are required
– increased frequency, duration and intensity of severe weather.
Some Arctic species already started shifting wintering and/or breeding areas, along with migratory distances and timing, and further global climate could result in altering migratory strategies to high-arctic year-round residency.
The objective of this symposium is to discuss the latest advances of various biological lines of research pertaining to polar-adapted birds and to identify important knowledge gaps for directing future studies. Due to a heightened awareness of increasing effects of global warming, an up-to-date picture of the rapid climatic changes in the polar regions are necessary. Further insight will be gained from understanding the mechanisms by which avian species in polar regions acclimate to a changing world and ultimately which will or will not be able to adapt.
Keynote Speaker: John C. Wingfield
Title: Weathering the storm: challenges for migrant songbirds in the Arctic.
Contribution of the keynote speaker to the field
Dr. John Wingfield is Distinguished Professor Emeritus at University of California, Davis, Professor Emiertus, University of Washington and has conducted environmental endocrinology research on arctic-breeding birds for over four decades. His studies have focused on mechanisms of coping with environmental stress in songbirds that breed in the high Arctic. These coping mechanisms are central to how birds acclimate and adapt to global climate change. He is also a founder of the field of environmental endocrinology.
Poor mental health is on the increase, particularly in urban areas. At the same time there is robust evidence that interacting with nature can support improved mental health outcomes. Birds are an important component of these interactions, being noticeable, noisy, found throughout the landscape and active at the same time as people. Watching birds, listening to bird song and providing food for birds not only provides people with pleasure but also a host of other cultural services, such as a sense of place. Further, birds hold a significant and central place in many cultures, and their presence and conservation can play an important part in socio-ecological regeneration.
Research that unpicks their specific contribution to mental wellbeing is still relatively in its infancy. While the majority of research to date has largely focused on Western countries, in recent years there has been an increase in the number of studies from diverse cultures and countries. Further, there has been prominent discussion about the potential negative effect of birds in some instances when they live in close proximity with people; the behaviours of some individual birds can result in conflict such as through the damage of property or when they are aggressive or noisy.
Given this emerging and diversifying focus of research the IOCongress™ is timely and well-placed to host this symposium. The goal is to showcase current research to scientists and birders from around the world to instigate conversations and collaborations to further advance this field, and ultimately encourage a greater number of international and cross-cultural studies. Finally, the symposia will highlight how the emergence and increased affordability of new technology makes this an exciting time to be working in this field.
Steroid hormones act on a wide range of phenotypic traits to orchestrate complex responses at the organismal level, such as reproduction or stress. One remarkable observation that has become clear in recent decades is that the brain itself is a key target for the multifaceted actions of these hormones. Behavior and aspects of physiology regulated by the brain must be coordinated with other traits for a successful functional response. One way steroids act on brain function is by modifying cell and molecular events in the brain. These events include changes in gene expression and modifications of the survival and recruitment of key cell types such as neurons. Songbirds exhibit remarkable seasonal changes in various aspects of behavior and brain function and represent and excellent taxon in which to study steroid hormone regulated brain plasticity. In this symposium we would like to highlight many recent advances in the work on hormones, brain plasticity and vocal control primarily in a variety of songbird species.
The study of the hormonal regulation of reproduction and courtship in birds has a long history going back to the 1940s. In recent years modern methods in cell and molecular biology have been applied to the analysis of these questions. Much of this work has been published in journals not usually referenced by ornithologists. Therefore, this symposium will review recent findings of general interest for all ornithologists including brain mechanisms controlling avian communication, brain plasticity (a topic initially discovered in songbirds) and the multi-faceted aspects of reproductive hormone action.
Gregory F. Ball: “Steroid Hormone Regulation of Birdsong: Neuroplasticty and Neuromodularity”
Jacques Balthazart: “Testosterone, brain plasticity and perineuronal nets in songbirds”
43. A genomic perspective on East Asian avian biodiversity
Yanhua Qu, Frank Rheindt
Asia has a great diversity of habitats, ranging from Arctic tundra to tropical forests, and including the highest mountains in the world. This is reflected in the region’s immense richness in birds, with more than 3,000 species. This habitat diversity in combination with climate change during the Pliocene and Pleistocene have been some of the main drivers of this this diversity. Recently, with the advance of new molecular and genomic tools, it has become possible to better understand the speciation and adaptation mechanisms underlying this extraordinarily high diversity. This symposium will focus on understanding the relationship between genomic change and the evolutionary forces promoting speciation in East Asia. For example, how have mountain and island barriers promoted geographic isolation and speciation, and how have land bridges between isolated islands during glacial periods allowed for gene flow between previously separated genetic lineages. As genomic data become more easy to generate and methods are ever further refined, we are coming closer and closer to unraveling the mechanisms that have produced Asia’s extraordinary avian diversity.
44. The genomics of hybridisation and speciation
Alexander N. G. Kirschel; Reto Burri
Ornithology has a long history of research into the patterns and processes involved in the evolution of species. Traditionally, this interest was pursued by assessing differences in anatomy and plumage coloration and their association with species limits. More recently, these studies have been complemented with ones that studied the role of bird song in mediating species recognition and sexual selection, and ultimately its role in speciation. In parallel, genetics have revealed a wealth of afore undetected avian diversity as well as unexpected species relationships not recognizable on the phenotypic level – leaving us with numerous questions on the origin of species and phenotypes and the processes under which they evolve. Today, genomics provide us with unprecedented tools to address these questions.
The aim of this symposium is to explore the latest developments in speciation research involving genomics, with a particular focus on the role of hybrid zones therein. Hybrid zones not only offer unique opportunities to identify regions of the genome involved in the maintenance of species barriers. They also enable us to associate specific genes with traits that may be important in the divergent evolution of species and provide insights into the role of gene flow in adaptation. In this symposium, we aim to cover a set of studies in birds that have involved genomics to understand the extent to which species hybridise and the consequences of hybridisation on the speciation process. Those consequences might include reinforcement against hybridisation thus maintaining species limits, collapse of species boundaries, and even hybrid speciation. We will also examine how with genomics we can identify genes associated with evolutionary divergence in traits potentially involved in speciation, ranging from plumage coloration and song to morphological and behavioural change associated with commensalism with humans.