What's living in your rivers? Each week, we describe a species found in Philadelphia's waterways.

PWD's Joe Perillo with an American shad caught near the Fairmount Fish Ladder

In honor of Shadfest—Penn Treaty Park's annual celebration of arts, music, food, craft beer and the Delaware riverfront's past and present—this week we're featuring the American shad. Alosa sapidissima is a Philly fish through and through: Known as one of the hardest-fighting freshwater species, author John McPhee dubbed the American shad "the founding fish" in a book of the same name, highlighting massive spring migrations in the 1700s.

Pollution in the Delaware decimated the shad population in the early 20th century, but the fish began its comeback in the 1980s. Check out the Fairmount Water Works Interpretive Center's Fish Cam to see if you can catch a glimpse of some shad during their spring run.