American shad larvae start to hatch from eggs collected from the Potomac River at the Van Dyke Research Station for Anadromous Fishes in Port Royal, Pennsylvania. Anadromous fish, like shad, live their adult lives in the ocean, but migrate back to freshwater rivers and streams to spawn.
Shad are an iconic species of the Chesapeake Bay region, but a combination of pollution, overfishing and the blocking of their migratory paths has led to a decline in their populations. To help boost shad numbers, federal, state and tribal governments have raised young shad in hatcheries and released them in rivers across the region.
But in order to sustain a stable population, shad need to be able to reproduce for themselves. As migratory fish, they require clear passage from the ocean to where they spawn in the Chesapeake’s freshwater tributaries, but barriers such as dams and culverts block waterways and separate shad from their spawning areas. The Chesapeake Bay Program’s Fish Passage Workgroup works with state agencies, local governments and nonprofits to remove these barriers where possible.
There are some places where barriers can’t be removed, such as the Conowingo Dam on the Susquehanna River, so the dam’s owner, Exelon Corporation, built a fish lift to help transport shad upstream. Unfortunately, despite some early success with the lift—transporting as many as 193,000 shad in 2001—annual catches have been steadily declining, with only 8,341 shad transported in 2015.
In an attempt to increase those numbers, in April 2016, the U.S. Fish and Wildlife Service announced a 50-year agreement with Exelon to help American shad migrate up the Susquehanna River to spawn. Exelon agreed to make structural changes, including improvements to the fish lift, to help attract shad to the lift and create enough room so they aren’t crowded out by other fish. The company also pledged to truck up to 100,000 shad upstream.
Learn more about the important role shad play in the Chesapeake Bay ecosystem and the work being done to restore them.
Image by Will Parson