The Hudson River lacked the necessary spawning and nursery capacity to maintain salmon. The first major tributary, the Mohawk River, entering from the west above Albany, was impassable due to the 70 foot falls at Cohoes.

Historically, the Hudson River was not a primary spawning ground for Atlantic Salmon, though it is a common misconception due to the river's massive abundance of other migratory fish. In the 18th and 19th centuries, the river was world-famous for its Sturgeon and American Shad populations, which were so plentiful they were nicknamed "Albany Beef." While Atlantic Salmon were occasionally found in the Hudson, they were usually straying individuals from more northern rivers in New England or Canada. In the late 20th century, there were experimental attempts to introduce salmon to the Hudson, but these failed largely because the river's water temperature during the summer is often too warm for salmon to thrive. In 2026, the Hudson's ecological focus has shifted toward the recovery of the Atlantic and Shortnose Sturgeon, both of which are federally protected. While you won't find a salmon run in the Hudson today, the river remains a critical biological corridor for hundreds of other species that rely on the transition between the Atlantic salt water and the fresh water of the northern highlands.