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Summer 2021 Smallmouth Bass Sampling

Each year, Virginia Department of Wildlife Resources (DWR) samples for Smallmouth Bass (SMB) age 0 (approx. 60mm in length) in the Shenandoah River to gauge the success of spawning. Sampling generally occurs once in April-May and again in October. Samples of the young of the year are collected through electroshocking. The fish are counted, inspected for bacterial infections, and some are collected to be tested by the US Fish and Wildlife Service’s Fish Disease Lab in Lamar, Pennsylvania. Data collected in October is used to determine the year’s spawning success. This year, DWR conducted additional sampling in July and August on the North Fork, South Fork, and Main Stem of the Shenandoah.

In response to an angler’s report of several distressed and diseased baby Smallmouth Bass near Front Royal, DWR took samples in July on multiple sites along the South Fork of the Shenandoah, from Rockingham County to the Main Stem Shenandoah at Lockes Landing. In early August, in response to the harmful algae bloom, samples were completed on the lower North Fork. Sites included Riverton, Strasburg, Deer Rapids, Headley Bridge, Seven Bends State Park, Red Banks, Meems Bottom and New Market. DWR collected fish in 50 meter reaches along the shoreline at each site using backpack electrofishers, and recorded water temperature and dissolved oxygen levels for each location. Generally, sample sites were within a few feet of the shoreline, typically in 2-6 inches of water.

On the South Fork, DWR found an abundance of age 0 SMB at all locations. Some of the Main Stem sites had high numbers as well. No distressed or dying fish were found, but a few were noted to have “bacterial funk”. Samples of these fish from each location were sent for testing. The temperature and dissolved oxygen levels were found, at all sites, to be within a healthy range.

The North Fork was a bit of a different story. Over eight sites, a total of seven Age 0 SMB were collected. These seven fish were caught from three sites: Seven Bends State Park, Red Banks, and Meems Bottom. Unlike the South Fork, no overabundance of age 0 SMB were seen avoiding capture. Of the seven collected, one fish showed signs of bacterial infection, and was sent for bacterial and virological analysis. These numbers aren’t necessarily indicative of the overall spawning success, as these sampling locations differ from the routine samples taken in the spring and fall. October sampling data will round out the picture of the success of Smallmouth Bass spawning this year.

The DWR is currently asking citizens, landowners, anglers, etc, to contact the DWR or DEQ if there are any diseased or distressed fish, or multiple dead fish observed. Fish with a bacterial infection will have “white patches” and distressed fish generally will not flee when approached. See below for how and when to report to DWR and/or DEQ . 

Sick Fish
If you see a diseased or distressed fish, please email a single picture of the fish showing the lesion or infection(s) along with the species of fish (if known), date of observation, and location fish was captured or observed (example:  North Fork Shenandoah River near Woodstock) to Jason Hallacher, DWR Fisheries Biologist for the Shenandoah River Watershed at

Dead Fish
Fish die of natural causes (even disease), so DWR does not want the public to report every individual dead fish that they observe.  However, if there is more than one dead fish observed in a reach of river/stream, please report this observation to DEQ in the Harrisonburg Office at 540-574-7800.   Make sure to note the date, location, species, size, and number of dead fish observed.