1. Physiological adaptations for breeding in birds
Research in the Williams’ Lab integrates life-history theory, ecology, physiology and behaviour. My book Physiological Adaptations for Breeding in Birds (2012) provided a critique of the state of our knowledge on the physiological mechanisms that underpin variation in life-history traits (e.g. phenology, fecundity, parental effort, productivity) and trade-offs (e.g. costs of reproduction). It focused on individual variation in, and took a strongly female perspective on, avian reproduction. For the last 6 years my NSERC-funded research has pursued studies to obtain empirical data to address the thesis outlined in Physiological Adaptations in relation to timing of breeding, hormonally-mediated maternal effects (egg size, yolk hormones), clutch size, and parental care (see Selected Publications). For the next 5-6 year NSERC cycle our European starling work will focus on individual variation in the parental phase of reproduction, from both the parent’s and the chick’s perspective, from the novel perspective of exercise and training in free-living animals (see edited ICB Special Issue, 2017). Exercise involves “movement supported by sustained locomotor performance, cardiovascular adaptations, and increases in energy expenditure above basal levels”. Clearly, such a broad definition can theoretically be applied to many routine activities in free-living animals, e.g. foraging, escaping predators, finding mates, providing parental care. These routine activities are essential for reproduction and survival, and costs of ‘under-performing’ are a matter of life and death for free-living animals – unlike human athletes at the Olympics! However, it’s currently unclear if concepts such as “exercise” and “training” apply to free-living animals? Do natural populations harbour “couch potatoes” and athletes? How do free-living animals prepare for, and deal with, rapid transitions in workload or locomotor performance?
Our research primarily combines studies of a free-living, nest-box breeding, population of European starlings (Sturnus vulgaris) – where we use an automated radio-tracking system to follow females 24/7 - and laboratory studies using captive breeding zebra finches (Taeniopygia guttata) – which we can “train” for high foraging effort. However, recent projects (and collaborations) have involved a wide range of species including song sparrows, blue tits, Arctic-nesting ducks and geese, seabirds, and even penguins and albatrosses!
Many of our toxicology-related research projects are conducted in partnership with the Centre of Wildlife Ecology and Dr. John Elliott, Environment Canada and scientists at the National Wildlife Research Centre (NWRC) laboratory in Ottawa.. Collaboratively, we aim to: 1) obtain a better understanding of the fundamental mechanisms underlying individual and population-level variation in physiological traits in order to provide a solid basis for predicting how animals might respond to environmental change; 2) determine more meaningful intra-specific measures of body condition, quality and individual health for birds; 3) develop and apply new physiological approaches and techniques to conservation biology and ecotoxicology. We approach these aims through a combination of studies on basic physiology, often using tractable model systems (e.g. zebra finches) as well as free-living birds (starlings, western sandpiper), coupled with more applied, and more specific, goal-orientated projects (e.g. addressing current eco-toxicological problems; see Selected Publications). Over more than 20 years we have investigated effects of many priority xenobiotics, e.g. current-use pesticides, arsenic-based pesticides (for pine beetle control), endocrine-disrupting chemicals. On-going projects are focusing on a) Long-term effects of early (in ovo or perinatal) exposure to mercury in birds: and b) effects of chronic toxicity of petroleum hydrocarbons (diluted bitumen) on birds on the Pacific north-west coast.