Stocking bass in N.C. coastal rivers is a problematic solution after hurrican-related fish kills, but full recovery depends upon time’s healing effects.
North Carolina hasn’t suffered a Katrina-like hit since 1999 (Hurricane Floyd), but the Tar Heel State makes up in numbers of storms for its relatively few direct hits by Category 4s.Hurricane Charley smacked the coast Aug. 18, 1986. Ten years later, Tropical Storm Arthur made an appearance June 20, 1996.
Since Arthur, seven hurricanes — Bertha, Fran, Bonnie, Dennis, Floyd, Isabel and Charley — have thrown combination punches at the state. Tar Heels have grown so accustomed to regular coastal devastation, they named the state’s lone NHL franchise the Carolina Hurricanes.
It doesn’t take a doctorate to see the numbers of hurricanes affecting North Carolina are on an upswing and show the state can expect to deal with the effects of a direct hit about once every four years, while a tropical cyclone will affect the state about every 1.3 years.
“We’re definitely in an upswing right now,” said Chad Thomas, coastal fisheries research coordinator for the N.C. Wildlife Resources Commission. “We’ve actually had 13 or 14 storms since 1996 that have had an impact on our coastal rivers.”
It’s the impact of these hurricanes and tropical storms that have caused the largemouth bass fishery in the coastal rivers to become a research manager’s nightmare.
“It seems that every time we get recovered from one storm, here comes another,” Thomas said.
The WRC actually began a project to stock four coastal rivers — Chowan, Pasquotank, Perquimans and Scuppernong — before the devastating landfall of Hurricane Isabel during September 2003.
The goal was to increase the numbers of bass greater than 14 inches. This project was pushed to the side after the enormous fish kills associated with Isabel.
“We were looking to stock 2-inch bass in those four rivers to try and boost the existing bass population,” Thomas said. “We were seeing an abundance of bass at certain levels, and we were trying to get the numbers of bass higher by stocking fish on top of other fish in hopes of improving the overall population.
“We stocked a number of 2-inch bass and had planned on following them throughout the fall. From what we saw, these 2-inch stockings had little, if any, impact. Then Isabel hit.”
The results of Hurricane Isabel during September 2003 were catastrophic for the Chowan and Roanoke rivers. Fish kills stretched up and down the rivers because of rapid rises and falls of water.
“We had a tremendous amount of dead fish in these two systems because we got a lot of water that flooded the back swamps,” Thomas said. “Along with the rapid rising of water, we had a rapid flush of the swamps into the creeks and main river channel. The result was a drop in oxygen that happened so rapidly the fish couldn’t escape.”
The already low oxygen levels of a late N.C. summer were diminished, if not altogether depleted, in the Chowan and Roanoke systems.
Thomas said the WRC was waiting on the replenishing effects of the upcoming cooler months, but Isabel forced the issue.
“It all happened so fast the fish couldn’t escape their deaths,” he said. “Hurricane Floyd, which was the precursor to all our stocking work in the coastal rivers, saw spotty fish kills but nothing of the magnitude of Isabel.
“What we saw with Floyd were areas where oxygen went to 0, but there were no dead fish because it happened slow enough to allow the fish to escape downstream.”
Isabel didn’t offer the same courtesy. Thomas said he likens it to throwing someone into a lake. Most people will try to make it to the surface before they draw their next breath. If they reach the top, they survive; if not, they die.
The fisheries devastation led the WRC to begin looking at the possibility of restocking the Chowan and Roanoke with 2-inch fingerlings — the same effort that worked miserably during the project before Isabel hit. The thinking this time, though, was there weren’t enough predator fish left after the kill to prey on the tiny bass.
Thomas also had discovered stocking on top of an existing population didn’t work well in coastal rivers, but there wasn’t enough of an existing population left in the Chowan and Roanoke to matter.
“In our early stockings before Isabel, we sampled an area a day after they turned the 2-inch bass loose,” Thomas said. “We found all our fish in the stomachs of warmouth and other small largemouth. Obviously, stocking such small fish on top of other fish didn’t work. However, this situation after Isabel was different. There weren’t any other fish. We were just trying to get something going.”
The WRC began the first phase of its river restoration project by searching the country to see what was available. They also looked at other stocking programs across the Southeast to see what was working and what wasn’t. The result was a decision to skip the 2-inch stage and go with 6- to 8-inch fish.
They found a private producer that was a source of 8-inch bass during February 2004, and purchased 12,000 bass minnows at $2 apiece with the help of Bass Pro Shops and RBC Centura. Six thousand sub-adult bass were stocked in the Chowan River, and 6,000 were stocked in the Roanoke River.
“We inserted microtags in the cheek muscle of each of those fish,” said Thomas. “The chips were about 1 millimeter in length — about the size of a splinter. Each chip had a code on it so that we could recover it and wave a metal detector over it to determine whether it was ours or not.”
The 8-inch bass were stocked “Johnny Appleseed” style by scattering them along stretches of shoreline measuring about 2/3 mile. Thomas’ crews poured out the baby bass and took a wait-and-see approach.
Once the 8-inch bass were in the two systems, the WRC thought the 2-inch bass used in previous years might work because there wasn’t really anything around to eat them either. Only, this time, they decided to super-stock them.
“We realized that stocking the 2-inch fish would be cheaper,” said Thomas, “so we had a crew of seven microtag 46,000 fingerlings, one at a time. It took us two weeks to tag them into different batches. We decided to stock them in the same rivers but at different stretches of shoreline.”
Thomas and his crew distributed the 2-inch fingerlings at different rates at different areas. One stretch received 1,500 fingerlings while another area got 10,000. The thinking was not only should the size of the fingerlings be considered, but the rate should be considered as well.
“We actually held over some 2-inch fish at the hatchery and fed them minnows until they reached 5 inches,” Thomas said. “We stocked 8,000 5-inch fish during the fall of 2004.
“All those were tagged and are at large. Now we’ve got fish at large from three distinct stockings. We implanted the chip in a different location of the head in the different groups so we’d know which stocking a future recovered fish came from.”
The WRC has exhausted every effort to see if stocking really works in coastal rivers. The point of the research is to see how they can best spend angler resources. If buying and stocking doesn’t work, the agency will have to find another remedy.
“What we have found since September 2004,” said Thomas, “is four of the 46,000 2-inch fish and one of the 8,000 five-inch fish. It’s pretty easy to conclude that the 2- and 5-inch stockings weren’t successful in the Chowan and Roanoke.
“It’s discouraging, obviously, to do that much work and not get the results you’re looking for. But it falls in line with what we saw in the past — stocking over natural populations just doesn’t work in the coastal rivers.”
However, what Thomas discovered through sampling was the movement of native fish back into the areas that were void of life before the stockings. Even though the Roanoke had miles and miles of dead fish after Isabel, Thomas saw it didn’t take long — about six months — to see significant numbers of fish moving downstream or upstream.
“These fish move back in and begin repopulating,” he said. “We sampled some areas where we put 2-inch fish a year after the fact and found two pound bass that didn’t beep, so we know they weren’t ours. They had to move back in from somewhere else.”
The underlying component is time. It takes time for coastal rivers to rebound from the effects of a hurricane. Thomas said the magic number is three years.
“During the spring of 2003, right before Isabel, we were right back at where we were before Hurricane Floyd,” Thomas said. “That’s a lag time of about three years. We were about to make a conclusion of our post-Floyd efforts when Isabel hit. We had to start from scratch all over again. We knew it would come back. The question was would stocking bolster it and bring it back quicker. The 2- and 5-inch fish weren’t the answer. The 8-inch fish, on the other hand, were quite interesting.”
Of the 12,000 8-inch fish stocked during February 2004, 100 of them were found about six weeks after they were released. In fact, the only fish that Thomas found in some of the creeks were from the 8-inch stocking.
“We found that there were either no fish at all,” he said, “or that all the fish were ours. Over time, bass started moving out of our spots. They seem to be doing OK and contributing now.
“I’d say the 8-inch stocking was a benefit to the overall fisheries. The only problem is that, over time, those fish eventually left those creeks where we really needed them, so I’d have to say it wasn’t successful at the point where they were needed.”
The numbers of the 8-inch fish recovered dropped from the 30s to the mid 20s each sampling throughout 2005. They were found to be growing but reducing in number overall.
“We went back this past fall and concluded all the ones we stocked 1 1/2 years ago did contribute to the local population,” Thomas said. “We’ve found them as far as 2 miles away from where they were stocked. But, even though we found them, we continue to see that native largemouths outnumber them. Maybe enough fish have moved back in to make our proportion small enough to being almost insignificant in the big scheme of things.”
This past fall, the North Carolina Bass Federation held a tournament at Edenton. State biologists were on hand to scan all the bass brought to the scales. The two-day event allowed anglers to fish any of the coastal rivers, and 191 bass were brought in during the two days.
“We scanned 81 fish between 14 and 16 inches — the range our fish should be,” said Thomas. “We found five on the first day, 11 percent. We didn’t recover any on the second day. That dropped our total percentage to 6 percent.”
Thomas said the results could be interpreted a couple of ways. First, the angler with the fish in his bag was thankful for the stockings. On the other hand, 94 percent of the fish that were caught were native fish.
As a biologist, Thomas said he thought that result was great because it meant reproduction is high and the system is supplementing itself.
“We went into a creek that had the 8-inch stocking and saw tremendous clouds of bass fry,” said Thomas. “Obviously, the fish have been getting in some good spawns. It doesn’t take a lot of adult bass in an area to repopulate an area quickly. If we can have 20 to 30 of our fish mixed in with a few 2- to 4-pound river fish, the area will quickly repopulate, especially with the reduced predation from hurricane-related fish kills.”
The most encouraging sign Thomas pointed to was something that happened after Hurricane Floyd. He found zero bass in a stretch of river after the storm. Two years later, he found a creek full of 18-inch bass at least 5 years old.
“Where did they come from?” he said. “They didn’t have enough time to hatch and grow since Floyd. The key is to hope we don’t get another hurricane around here for a while as it’s building back from the effects of Isabel.”
Stocking bass in coastal rivers of North Carolina can help expedite the process of bringing largemouths back after a catastrophe, but the best remedy may be one of the oldest cliches — time heals all wounds.
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