Foraging Ecology, Nutrition, and Energetics

This chapter examines how the need to acquire food—both in quantity and quality—shapes the ecology and management of migrating and wintering waterfowl. Foraging decisions are tied not only to energetic demands but also to broader life-history events such as molt, migration, and pair formation. Energy and nutrient needs vary across time, species, and environmental context, but are fundamentally constrained by how waterfowl gather, process, and store food. Advances in nutritional ecology and energetics modeling have transformed conservation approaches, replacing coarse habitat proxies with bioenergetics frameworks that link food availability to population-level outcomes. Nutrient storage plays a central role in enabling long-distance migration and supporting reproduction, with carry-over effects evident across the annual cycle. Patterns of food limitation may emerge during winter, particularly in colder climates or under resource scarcity, with implications for survival, behavior, and future breeding performance. Agricultural landscapes have reshaped diets and distributions for many species, increasing carrying capacity but raising concerns about nutritional balance and dependence on shifting human land use. Understanding how foraging behavior, food quality, and energetic constraints interact remains essential to developing habitat strategies that support resilient waterfowl populations throughout the non-breeding season.