They're known as "Christmas shad" because American shad, starting their annual migratory spawning run, can be caught at the lower Cooper River during Christmas week.

The ocean fish are the vanguard of a five-month ascent up the Cooper, near Charleston, a migration that peaks from mid-March to mid-April when the fish queue up to the Pinopolis Dam at Lake Moultrie.

The first Christmas shad, as angler Ralph Phillips of Summerville calls them, usually start moving Dec. 15-20 from the Atlantic into the lower Cooper.

They reach the Williams Station canal about 20 miles upstream between Christmas and New Years. That's a period when cold weather often leaves a dead spot in the fishing season and shad provide a timely alternative to sitting in front of the TV watching endless football games.

The power plant is located about 1½ miles upstream from the confluence of the Cooper and Back River. The plant's warm-water discharge attracts American shad and their smaller and less numerous cousins, hickory shad.

"The colder the water in the river, the more they concentrate around the discharge," said Phillips, who's fished for shad at the Cooper since 1969.

Phillips launches his boat from the Bushy Park public ramp off S.C. 503 and goes upriver about 2 miles. The plant's 400-foot-high stacks serve as landmarks for the discharge canal on the west (left going upstream) bank.

Shad turn off the Cooper and swim into the warm water, obeying age-old instincts to follow a current. Here, Phillips said, the schools make long loops up the canal and back out into the river.

"They mill around," he said.

The canal is open to boat fishing. Phillips recommends anchoring as close to the end of the 200-foot-long canal as allowable. Spokesman Robin Montgomery of S.C. Electric & Gas said no tie-ups to structures are allowed; neither is bank fishing.

Like other shad anglers, Phillips uses ultra-light tackle, spinning rods with 4- or 6-pound-test lines. He ties on a shad lure, a 1/8- or 1/16-ounce yellow or pink jig head with a chartreuse soft-plastic curly tail.

American shad, which eat tiny plants and animals, don't feed on their migration runs. They, like salmon, will strike lures reflexively, perhaps out of annoyance, although no one knows for sure.

Phillips lets the lure float to the bottom, keeps a tight line with no slack, and then retrieves it slowly. Expect a soft bite; don't rip the line when the fish strikes, just tug it to set the hook. Shad have delicate lips.

Otherwise, "you'll tear it out of their mouth," Phillips said.

For Christmas shad, he urges anglers to patiently work their lures. Four or five fish make a good trip this time of year unlike the 30- to 40-fish days in the Pinopolis Dam tailrace in late winter or early spring.

"It just requires more patience," he said. "You don't have the number of fish there. Let the bait settle and sink. Slow down. It's a slow fishing game. But it beats sitting on the couch."

Strong swimmers, shad are a lively game fish. They often jump into the air when hooked, hence the name, "poor man's tarpon."

Shad aren't the only fish that enter the canal. So do crappie, catfish and largemouth bass as well as saltwater fish such as striped bass, spottail bass (redfish) and flounder, said Jarrett Gibbons, a S.C. Department of Natural Resources fisheries biologist who has fished the canal for shad numerous times in late December and January. Anglers should rig a rod or two for the larger fish so, as they wait for the next school of shad to pass by, they can multiply their chances for success.

The creel limit for shad is 10 fish per day at the Cooper and all other S.C. rivers except the nearby Santee. In the Santee and the Rediversion Canal, which links the river to Lake Moultrie, the limit is 20 fish per day.

There's no minimum-size limit. Only a freshwater license is needed for the warm-water canal and farther upstream.

In March, 2005, I fished with Phillips and Capt. Adam Ridgeway, a Charleston guide (www.charlestonfishingguide.com), for a half day in the Tail Race Canal at the Pinopolis Dam near Moncks Corner, 80 river miles from the ocean. We anchored beside the bank several hundred yards below the dam.

We waited out a strong release from the dam's turbines. After the flow subsided, and the water dropped about 3 feet, the strikes began as shad moved up the tailrace. We caught 12 in two hours, including a 3-pounder, biggest of the trip.

Six years ago, Phillips caught his biggest shad in the tailrace.

"That was a hell of a shad," he said. "Never jumped, never came to the surface."

The fish weighed 6 pounds, 14 ounces, just shy of the state record 7-pounder caught in 1985 at the Santee River.

Ridgeway said he fishes the tailrace for fun until redfish activity picks up.

"You can have 30-, 40-fish days in a couple of weeks," he said. "It's not the 100-fish days that they have on the Roanoke (river in North Carolina). But the fish are bigger."

Gibbons, the DNR biologist, said 186 surveys of anglers fishing the tailrace between Feb. 28 and April 8, 2005, showed fishing parties (of one to eight anglers) caught 954 American shad, 245 blueback herring and 18 hickory shad. The parties landed 0 to 30 fish per trip, with an average of five fish.

Shad spend the summer off Canada. They head south in fall, swimming through a gauntlet of predators. Those fish born in the Santee-Cooper drainage area assemble off the S.C. coast awaiting a temperature signal to begin their spawning run.

During the run, Pinopolis dam operators periodically open the lock to allow the accumulating shad to pass into Lake Moultrie. From Moultrie, they can swim through the Diversion Canal into Lake Marion and then up the Congaree and the Wateree rivers to historic spawning grounds.

Gibbons said he couldn't provide the number of shad passed through the lock into Moultrie. A counter registers all migrating fish as blueback herring. Last year, 1,375,014 "herring units" swam from the tailrace into the lake.

Shad moving up the Santee River go through the Rediversion Canal into Moultrie. Gibbons said 105,000 herring and 283,225 shad of both kinds passed from the Santee into Moultrie last year.

The Cooper and the Santee claim the largest American shad population on the East Coast, according to Prescott Brownell of the National Marine Fisheries Service in Charleston.