Our program focuses on the biology of freshwater and marine systems and the management and sustainable use of ocean resources. We work in aquatic systems around the world: Understanding the links among marine, freshwater and estuaries provides us with a broad perspective on factors that shape aquatic biodiversity. We study large-scale processes: how climate affects aquatic systems, how nutrients flow between organisms and their environment, how human structures affect water availability. We characterize and study the biodiversity of aquatic organisms: We describe the world’s aquatic biodiversity so that we can study their complexity and preserve our natural heritage. For example: we classify and catalog aquatic species in a museum collection accessible to researchers worldwide. We use genetic tools to identify species and describe diversity among invertebrate, fish, bird and mammal populations. We investigate how organisms interact with and influence their aquatic environments: We examine the factors that influence population abundance and distribution so that we can understand the scientific basis for the conservation of species and the areas they inhabit. Our ecological studies range from behavioral studies, to population ecology to community interactions with ecosystems. We study how individuals and species interact, why populations change over time, and how aquatic food webs are structured. For example: we tackle issues in restoration, and study the effects of invasive species, large-scale migratory patterns and factors affecting water and habitat quality. We explore how individual organisms are influenced by, and modify, their environment: We use sophisticated approaches to study physiological and genetic behavior in aquatic organisms, to anticipate how they might respond to natural and human effects. For example: we investigate how diseases spread through populations, how growth and reproduction is influenced by different environments, and how organisms might adapt to changes in their environment. We develop effective approaches to conserve and sustainably manage aquatic resources: We use innovative approaches to blend research disciplines, allowing us to advance solutions to a range of issues in the aquatic environment. We use quantitative methods to study changes in individuals, populations, species, ecosystems and human behaviors. For example: we use integrated approaches to define population units and cons