Image of an otolith marked with tetracycline as seen under a microscope. The bright green circular mark is the tetracycline tag on a daily growth ring on the otolith structure. Photo taken by Michael Hendricks, Pennsylvania Fish and Boat Commission (date unknown).

Harrison Lake National Fish Hatchery spawned, reared, and stocked approximately two million marked river herring fry into Kimages Creek, Charles City County, Virginia in 2007.  The stocking program is part of a cooperative restoration project with Virginia Commonwealth University to restore river herring runs to Kimages Creek, a tributary to the tidal James River.

Historically, Kimages Creek supported strong runs of spawning river herring each spring.  In recent years, no river herring have been observed at the mouth of Kimages Creek and the population using this stream is believed to be extirpated.  Virginia Commonwealth University (VCU) owns the lower end of Kimages Creek, including a small dam that blocks the stream to form Lake Charles on VCU's Rice Center property.  Efforts are underway to remove this failing dam in the near future, and the fry stockings are designed to rebuild a population of river herring that are imprinted to this stream and have the desire to return to the stream as adults in 3-5 years to spawn.

Staff from Harrison Lake NFH captured and spawned adult river herring (blueback herring) from the James River basin, treating the eggs experimentally to reduce their adhesive nature.  The eggs were then reared at Harrison Lake NFH, and the hatched fry were marked with tetracycline to identify them as being of hatchery-origin.  The tetracycline, a common antibiotic, creates a permanent tag on the ear bones of the fish that biologists can see using a special microscope.  The tagged fry were then released into Kimages Creek at the upper end of Lake Charles.  The Service and VCU will monitor the juveniles' growth and survival later in the summer, and plan on monitoring their returns as adults in future years.  The tetracycline tags will allow the biologists to identify hatchery-origin fish from wild fish, and help evaluate the success of the stocking program.

This stocking program is in its third year.  The Service and VCU began this project in 2005, with the initial focus being on the development of suitable techniques to spawn and culture river herring on a large scale.  The first year's work resulted in stocking approximately 209,000 river herring into Kimages Creek in 2005 and a culture protocol that allowed the program to expand and produce 0.9 million marked fry in 2006, and 2.0 million marked fry in 2007.