Surveys on the James River turned up 175 sturgeon this spring, the most since a coordinated research program began two years earlier. The catch also included 15 sturgeon more than 5 feet long.
But the most surprising catch may have been a mature male caught on May 30-the last day of the survey-which was releasing sperm into the river.
Chris Hager, a fisheries scientist in the Sea Grant Marine Advisory Program at the Virginia Institute of Marine Science, said biologists thought spawning in the James took place earlier in the spring.
Also, he said one of the fish tagged earlier this year turned up in Delaware Bay later during their spawning season, suggesting that some of the fish seen in the James in early to mid-spring may be en route to other more northern areas to spawn.
"The presence of these northern stocks in mid-spring suggests that the bulk of our fish aren't here yet and may be coming behind them," he said. "A lot of these mature fish that we've been putting tags in thinking we were going to track them upriver may be Delaware ore even Hudson fish."
Biologists are catching and tagging adult fish, hoping they will lead them to spawning areas that might need protection if sturgeon populations in the James are to rebound.
They are also tagging and tracking various year classes of netted fish to determine foraging areas, nursery areas and other habitats-as well as when the sturgeon are using them. These areas could then be targeted for protection in the future.
If James River spawning takes place later than literature suggests, the current monitoring program could be missing the majority of the spawning run, Hager said. He noted that Capt. John Smith also reported that sturgeon of about 4 feet were common in the spring, but "after the midst of June, those of two to three yards show up."
But Albert Spells, Virginia project leader for the U.S. Fish and Wildlife Service, cautioned against drawing conclusions from so few fish. "It probably raises some questions," he said. "But we haven't caught enough mature fish in late spring to come to that conclusion."