Linda A. Deegan Ph.D.

  • Senior Scientist
Linda Deegan

Dr. Linda Deegan grew up fishing with her parents and has traveled the globe seeking fish, from tetras in the Amazon to grayling in the Arctic, and bluefish in New England. Her work addresses the fundamental question of how environments support the plants and animals that live there, and how human impacts on habitat, nutrients, and climate are disrupting these connections. She is particularly interested in aquatic ecosystems because of their importance in connecting landscape elements through the flow of water, nutrients, and animals.

Dr. Deegan is a strong proponent of long-term monitoring and whole-ecosystem experiments. For twenty years, she has led The Tide Project, the world’s only ecosystem-scale nutrient addition experiment, based in the Plum Island Estuary system. This initiative has yielded important insights into the impacts of excess nitrogen on the physical stability and ecosystem functioning of salt marshes. More recently, Dr. Deegan has begun testing the impact of phosphorus on streams in the Amazon to better understand the impact of agricultural expansion.

Dr. Deegan volunteers with the Coonamesset River Trust, working to restore local cranberry bogs to habitat for native herring and educating students about fish migration and conservation. While she says she still lives to fish, she also enjoys gardening and walking in the woods.

It’s very important for me to be in the ecosystems I am studying. It’s not abstract to me. I need to see and feel the changes.


richly colored arctic landscape with orange grasses, a few tents in the foreground, and a light blue lake reflecting clouds of a dynamic array of greys

Evolving Meta-Ecosystems Institute

Investigating the resilience of Arctic organisms and ecosystems to rapid climate change

The TIDE Project

Long-term experimental ecology at the scale of the ecosystem and unique in the world.
Two human figures darkly silhouetted against an orange sunset

Woodwell Climate @ Tanguro Field Station

Probing tropical ecosystem dynamics at the world’s largest agricultural frontier