"It is interesting to note that these fish kills occurred sequentially, rather than simultaneously, and that they have occurred only during the last four years," Kain continued. "One would expect that weather patterns, runoff, chemical use and timing, etc., would be very similar among the three watersheds and that flows and water quality variability would follow similar patterns in all three watersheds. The movement of the fish kill events from west to east over time follows a pattern one might expect from a disease that is carried by fish or another host as it spreads through a basin. Also, the fact that not all fish are dying at the same time suggests something other than a single water quality 'event.' The pathology reports to date have not demonstrated any disease or harmful parasite."

If there is a positive aspect, it is that we have seen a very strong year-class of smallmouth bass from the 2004 spawn. These young fish seem unaffected by the kill, are present in high numbers in both rivers, and seem to have excellent growth rates. Despite the fish kill, adequate brood-stock fish remain in the river.

"In a couple of years, barring a recurrence of this kill or other serious environmental event (such as drought or a major flood), the fishery may be very strong," Kain said.

DGIF district fisheries biologist Steve Reeser agrees with Kain's analysis and adds these comments.

"We continue to look at the similarities of the fish kills that occurred on the South Branch and the kills on the North Fork in 2004 and South Fork in 2005," he said. "We have had discussions with West Virginia DNR and Maryland biologists regarding these events and will continue. With the kill occurring in subsequent years and appearing to move south to east in the Potomac watershed, we wanted to investigate the possibility of a virus or other pathogen causing the kill. We have taken fish with lesions to the U.S. Fish and Wildlife Service's Fish Disease Lab in Pennsylvania to check for known fish viruses as well as other pathogens. I'm not sure when these results will be in."

He did say that they know the adult smallmouth bass and redbreast fisheries have been greatly reduced throughout the South Fork and mainstem Shenandoah. However, exactly how bad the situation is won't be known until more sampling is done, and that data compared with previous sampling.

"There was an excellent smallmouth year-class produced in 2004 and the young-of-year from it appear to be unaffected by this fish kill. We even saw this in the North Fork Shenandoah with the fish kill that claimed most of the adult smallmouths in that river. If we have a strong year-class produced in 2005, that will significantly help the recovery of the smallmouth fishery in the Shenandoah," Reeser said.

Catch rates of the 2004 fish should be high and these fish should be averaging 9 inches the summer of 2005. However, Reeser also pointed out that replacing the larger, older fish would take several years. With it taking six to eight years for a smallmouth to reach 14 inches in the Shenandoah system, rebuilding the population of quality-sized fish will take some time.

PHILPOTT AND SMITH MOUNTAIN LAKES
Dan Wilson is the DGIF biologist who keeps tabs on Philpott Lake and Smith Mountain.

"The last creel survey at Philpott was 1995," he said. "I would like to have another one, but the budget/part-time employee cuts have really limited creel surveys. We have been concentrating our creel time on waters where the most important management changes are occurring, such as the James River and the new slot limits."

Smith Mountain Lake has a 14-inch, two-fish regulation for black bass, meaning that only two of five bass creeled can be less than 14 inches. Wilson offers an interesting commentary on this regulation, which has been in effect a number of years.