BRUNSWICK — For the second consecutive winter, lower-than-normal temperatures in coastal Georgia drove down estuarine water temperatures to lethal levels for some marine organisms. The Georgia Department of Natural Resources and many anglers are concerned about the status of species that support the state’s commercial and recreational saltwater-fishing activities.
"Water temperatures in the mid-to-low 40s are lethal to over-wintering white shrimp and some fish species, such as spotted sea trout. We documented such water temperatures during a mid-December cold snap, again in late December and on some occasions in January," said Spud Woodward, director of the Coastal Resources Division of DNR.
In early December, the coastwide catch of white shrimp in the DNR trawl surveys was 11 percent above the long-term average. In mid-December, a cold snap caused the water temperatures in tidal rivers and creeks to plummet from the mid 50s to the low 40s in just a few days. Coastal Georgia continued to experience abnormally cold temperatures throughout December and into January. By February, the coastwide catch of white shrimp was 95 percent below the long-term average, and this trend continued in March with catches still 92 percent below average.
"The South Carolina Department of Natural Resources also documented very low shrimp abundance in their tidal rivers and creeks and requested NOAA Fisheries to close federal waters off their state to shrimp trawling for April until early June. Georgia DNR did not make a similar request, but we’ll likely delay the opening of state waters to food shrimp harvest so we allow more of the shrimp that survived the winter to spawn before being caught," said Patrick Geer, chief of marine fisheries for DNR.
Angler reports and observation by state natural resource agency staff indicate that sea trout populations in the Carolinas and Georgia also suffered from the cold winter. The North Carolina Division of Marine Fisheries prohibited the harvest of spotted sea trout in mid-January as a measure to conserve their surviving fish. The DNR also is concerned with the status of Georgia sea trout populations, but won’t know the extent of the impacts until the marine sportfish population health survey resumes this summer. However, based on the reports of fish kills from Savannah to St. Simons Island, the DNR is partnering with the Coastal Conservation Association-Georgia to encourage the voluntary release of larger spotted sea trout through Operation Release Over Eighteen (ROE).
DNR studies show that approximately 94 percent of trout more than 18 inches in length are females, so it is not surprising that many anglers refer to all larger fish as roe (egg) trout. Research has shown that larger, older females produce many more eggs than smaller individuals. An 18-inch female sea trout has the potential to produce almost 18 million eggs during the six-month spawning season — almost five times the egg production of a 14-inch trout. Plus, older fish have survival traits valuable in the gene pool.
"The voluntary release of larger trout is a great way for the average angler to directly participate in conservation while helping ensure there’ll be more fish to catch in the future. We started Operation ROE when we realized the winter of 2009/2010 had adversely impacted our sea trout populations. We had a good response from the fishing community and, fortunately, DNR surveys showed that our sea trout population fared better than we expected. However, the cold weather came earlier this winter and the impacts to Georgia’s fish populations may actually have been worse. I hope that anglers will once again do their part to help our sea trout population rebound from this winter," said John Duren, state chairman of CCA Georgia.