In the Delaware River, climate change and invasive species threaten shad, ‘America’s founding fish’

ZOË READ / WHYY – American shad were a major food source for early European settlers and Native Americans who lived along the Delaware River.

Known as “America’s founding fish,” the species were so abundant that it was said people could “walk across their backs.” In 1896, more than 4 million shad were caught in a single year. But by the 1900s, overfishing caused a steep decline …