Young American Shad project on the Delaware River

Posted 8/21/12

Every spring, fisherman flock to the Upper Delaware River to try their luck in catching migrating American shad; from May into June, shad migrate to the upper reaches of the river in order to spawn. …

This item is available in full to subscribers.

Please log in to continue

Log in

Young American Shad project on the Delaware River

Posted

Every spring, fisherman flock to the Upper Delaware River to try their luck in catching migrating American shad; from May into June, shad migrate to the upper reaches of the river in order to spawn. After spawning, many of the adult shad die, but some survive, to migrate downstream and back to the sea. Meanwhile, the fertilized shad eggs hatch, and the tiny shad fry spend the summer in the river. In the fall, these two-to-three-inch young-of-year (YOY) juveniles start their own migration to the sea.

This summer, the National Park Service (NPS) and several partner agencies are embarking on a project to sample YOY shad at various locations along the Upper Delaware in order to develop methods to monitor shad populations and to assess the importance of the Upper Delaware as a spawning and nursery habitat for this species. Shad populations have recently been at historic low levels throughout the East Coast, including the Delaware River Basin. Up until now, there has been very little data of YOY shad populations in the Upper Delaware.

Several locations along the river have been selected as survey sites. Survey methods include visual surveys by snorkelers, the setting of Fyke nets ( a net with a series of hoops in which flowing water sweeps shad into the nets), and seine nets (long nets that hang vertically). The most efficient of these methods is the seine net, but it is difficult to use when there are a lot of underwater obstructions (boulders, logs, etc.). Captured shad and other non-target species are released downstream of the net sets, so they don’t influence subsequent counts.

The American Shad is a vital part of the Upper Delaware River habitat and a prized resource by anglers. Many bald eagle nest surveys yielded an abundance of shad bones underneath nest trees. The YOY shad sampling project by the Upper Delaware Scenic and Recreational River and its partners will enable stakeholders to better assess the well-being of this species.

Comments

No comments on this item Please log in to comment by clicking here