Sarah Senécal

Université du Québec à Rimouski
Ph.D. candidate

Supervisor: François Vézina
Oliver Love
Start: 2021-01-11
End: 2024-12-21


Long-term consequences of individual performance in two costly life history stages
During their life, and within an annual cycle, species must face environmental constraints that vary according to their life history. These constraints not only generate direct short-term effects, but also visible long-term effects on physiological condition and individual performance. Individual performance is here defined as the ability, or not, of an animal to adjust its behavior or physiology in order to respond adequately to environmental constraints to maximize its fitness. The effects of energy constraints on individual condition may therefore affect individual performance by modifying, for example, the capacity to feed juveniles or physiological maintenance. A consequence of the direct and long-term effects of these stresses is the existence of individuals who differ in terms of condition within the same population, thus having different survival probabilities. The main objective of this thesis project is to study the consequences of individual performance in two energy-expensive life history stages, namely winter and the reproduction period in the black-capped chickadee (Poecile atricapillus) and the boreal chickadee (Poecile hudsonicus), two common non-migratory birds in North America. Annual follow-ups (winter and summer) will be carried out in the field to study the consequences of individual winter performance (cold endurance and heat production) on performance during the breeding season (effort and reproductive success), and vice-versa. In addition, by manipulating flight costs in the field, I will determine how the effect of increased flight costs on physiological condition (blood markers, muscle size, fat reserves, etc.) persist between life history stages (winter and summer). Finally, an experimental approach in a controlled environment will be used to determine the capacity and duration of recovery following an energy imbalance and a loss of condition in order to determine if the long-term effects are real, or result from a cascade of external seasonal events limiting the ability of individuals to recover. This project will be the first to compare the prolonged effect of performance between different life history stages at the individual level and to examine the mechanisms behind said performance. Linking physiological condition to individual performance and survival is a priority for making significant advances in our understanding of animal life history strategies in times of ecological constraints.


Effort reprodcuteur, Histoire de vie, Contraintes hivernales, Performance individuelle, Condition et état de santé, Effets à long terme, Écophysiologie aviaire, métabolisme, Valeur sélective