Fish in the lower James River got an early present last December when construction equipment gouged away a 200-foot section of an earthen dam that had made tiny Kimages Creek off-limits to migrating fish for most of the last century.
A week before Christmas, the equipment restored tidal exchanges between the creek and the James, clearing the way for what biologists hope will be the return of migratory fish, especially two species of river herring - blueback herring and alewife - whose populations are at near-record lows all along the East Coast.
"Given the really precarious state of river herring species, every little bit is going to help," said Greg Garman, director of the Virginia Commonwealth University Center for Environmental Studies.
Typically, it's the super-size fish passage projects that get the greatest attention, such as the blasting away of Embrey Dam on the Rappahannock River in 2004, or the construction of a multimillion-dollar fish elevator at the 100-foot Conowingo Dam on the Susquehanna River in 1991. In comparison to such mega projects, which often open hundreds of miles of habitat to migratory fish, last year's efforts in the Bay watershed were modest, with only about 100 miles of river reopened, according to figures from the Bay Program.
The tidal portion of Kimages creek is only about three quarters of a mile long and dwindles to a width of about 15 feet as it winds upstream. But the $50,000 project shows that small dam removals can have major effects on local ecosystems.
Not only does the project allow for fish migration, but the draining of the impoundment and restoration of tidal flows will allow for the replanting of marsh plants on more than 70 acres, making it one of the largest tidal wetland restoration projects on the East Coast. Those wetlands, being planted in partnership with The Nature Conservancy, will improve spawning habitat for river herring. They'll also improve habitat for birds - Kimages Creek is one of only two inland places in Virginia where a willet, a sandpiper normally seen along the coast, was sighted.
Biologists from the adjacent Virginia Commonwealth University Rice Center began thinking of restoring the creek in 2006. They had help visualizing what they wanted to restore from a Civil War woodcut illustration that appeared in Harpers Weekly. The woodcut, done during the Peninsula Campaign of 1862, depicted the winding creek and its marsh from a Union encampment on a overlooking bluff. But the stream was dramatically changed in the 1920s, when a hunting club built a 9-foot-high earthen dam to flood the valley with the intent of improving waterfowl hunting.
The idea of breaching the dam got a helping hand when several large storms partially breached it in 2007, restoring a free flowing stream to the James River, which was fewer than 100 yards away.
Prior to the natural partial breeching of the dam, electrofishing surveys had identified 10 fish species above the dam, including several nonnative freshwater species. Since the partial breeching, the number of fish species has grown to 16, as a number of species found in the James River have moved in, including bay anchovy, blueback herring and American eel.
Still, Garman said, the small stream wasn't creating much of a flow to attract fish. Now, with one quarter of the 800-foot dam removed, he is expecting to see increases in their numbers. Before the creek was dammed, spawning runs of herring and shad were great enough to support a small local fishery.
"Now that we've got a 200-foot-wide breech, we have the original Kimages creek channel dumping straight into the James, so we've got high hopes," Garman said.
To further jump-start efforts, several million larval river herring have been stocked in the creek since 2006 in partnership with the U.S. Fish and Wildlife Service's Harrison Lake National Fish Hatchery.
Garman said many small tidal creeks have been dammed in the past, cumulatively removing large amounts of spawning habitat for blueback herring and alewife, which live most of their lives in the ocean but return to their native rivers and creeks to spawn. Success at Kimages Creek could provide a model for those systems, he said.
"Probably every one of those systems historically supported river herring populations," Garman said. "With the herring species, a 6-inch impediment is enough to be a complete blockage."
Read the entire story in the Chesapeake Bay Journal....