Jim Wesson hauled the oyster dredge aboard the custom deadrise and dumped it.
The stench of rotting meat and the gaping shells confirmed reports he'd been hearing from local oystermen for days: Oysters in this section of the James River were dying.
A freshet, or freshwater event, had moved down from the headwaters of the James, lowering salinity levels and boding ill for the saltwater-loving oysters that had only recently made tentative inroads in this part of the river across from King's Mill in James City County.
"It all comes down — a freshwater wedge — and it pushes the salt out of the way until it stops running," said Wesson. "Then the tides push it back up."
Wesson is an oyster specialist with the Virginia Marine Resources Commission, or VMRC.
Freshets are normal for the river, and occur every five years or so, he said. They can be caused by heavy rainfall and hurricanes, with the last caused by Isabel in 2003.
If a freshet occurs in winter, he said, hibernating oysters can better survive. Summertime freshets are another matter.
"It just takes a few days of zero (salinity) and warm weather for the oysters to die," said Wesson.
In this particular area of the James, the real oddity isn't the freshet, he said, but that oysters were there in the first place.
Normally that area isn't salty enough for oysters to thrive, he said, and doesn't even have a reef or shoal name. But a few years of drought conditions made it more habitable for oyster larvae carried by incoming tides, until a few oystermen were even working the site.
"It's not unusual to see them killed — it's unusual to see them living for so long," said Wesson of the oysters. "They've kind of been on borrowed time."
On Monday, he was boating from the James River Bridge up to a shell dredging site near King's Mill and stopped en route to take oyster samples.
At the westernmost site at King's Mill, he found a nearly 100 percent mortality rate.
Just downriver at Deep Water Shoal across from the Deep Water Lighthouse, the mortality rate was about 50 percent.
Further down at Horse Head Rock, the rate was a mere 10 percent, which Wesson said is normal mortality for oysters.
He said he doesn't expect any impact on the oyster fishery this year, because the site affected is so small and the watermen working it so few.
According to VMRC, the struggling oyster fishery is showing signs of improvement, with harvests increasing nearly tenfold in a decade, from 23,000 bushels in 2001 to about 250,000 bushels in 2012.
Wesson said he still expects this year's numbers to top even that, estimating watermen will harvest 300,000 bushels.
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