Environment ❯ Ecosystems ❯ Aquatic Ecosystems

Freshwater Ecosystems

Crocodile Population Species Interactions Salmon Migration Adirondack Ecosystems Fish Populations Mosasaur Habitat Rivers and Lakes River Systems Ridley Park Lake Delta Region

Humpback Whale Tracked 60 Miles Inland in Sacramento–San Joaquin Delta

Officials are monitoring the identified whale to evaluate health risks from freshwater exposure, boat traffic, and stress.

Mosasaurs Lived in Rivers Near the End of the Cretaceous, Isotope Study Finds