It's fast approaching high season for one of the more satisfying fishing adventures on the middle Chesapeake Bay.

Three weeks ago, charter captains working the Stone Rock, a huge underwater oyster bar at the mouth of the Choptank River, were startled and delighted to see their depth meters light up as they crossed over hugh schools of sea trout.

These trout, also called gray trout or weakfish, have been visiting the Stone Rock every fall for the last five years to feed. This year marks their earliest arrival ever.

The catch of trout on the Stone Rock so far has been sporadic, but that is the way it traditionally begins. On skipper managed to boat 31 one day, along with several bluefish and some huge black drum, which made for a very exciting outing.

But on the other days the trout schools have appeared but refused to bite. And some days they didn't show up at all.

"It's like the fellow says," said Puddin' Manifold, who runs Manifold's Marina in Deal, Md. "This time of year you pay your nickel and you take your chances."

The nice thing is that the sea trout fishing always gets better as the season progresses through mid-October, when the fish depart again for deep water.

"We've got all kinds of fish there right now," said Dick Houghland, formerly a charter skipper out of Chesapeake Reach Rod 'n' Reel. "They just seem to school up better as the weather cools. The thicker the school, the better a chance you have to get them."

Last September, Houghland carried a party of fisherman to the Stone Rock early on a sparkling day and by the time afternoon arrived they had cought so many sea trout they were releasing the fish. I was on that trip, and it was quite an experience.

The Stone Rock lies about half a mile west of Sharp's Island lighthouse.

The lighthouse is easily identifiable. It sits at a cockeyed angle, the result of a losing battle with ice flows in the Bay several winters ago.

Once the lighthouse is in sight, a good fall sea-trout fisherman stops locking at the world and buries his head in the depth finder, which is the key to this kind of fishing.

He will meander across great swaths of the oyster bar, which extends for a great distance north and south. When the flashing band on the meter that signifies the bottom, 12 to 20 feet down, suddenly expands, he's probably found his school of trout.

The school may show up in either of two "modes," according to Houghland. "If it's a feeding school, It's likely to be spread across a wide expanse of bottom, and the fish will show up a foot or two thick. If the trout are on the move, they'll be tightly schooled and piled up seven to 10 feet thick.

Either way, the technique from that point on is the same. The idea is to get either upwind or uptide of the school and cut the boat engine so as the drift back over the fish. The fisherman case bucktails of about a half-ounce, with pork rind tails attached upwind or uptide and retrieve them slowly through the gathered fish.

Cut crab baits and even cut menhaden also work.

It takes a deft tough to keep the bucktail or bait moving just off the bottom, where the trout are seeking their food.

Because the water is fairly shallow and unobstructed, high-sport anglers can use light or even ultralight spinning tackel. The man with most success in our party was using six and eight-pound test line, which sounds ridiculous for fish that ranged up to 11 pounds. But he proved it wasn't by catching about 25 trout himself, and had a ball doing it.

By midafternoon that day we had better than 60 trout, six pounds or better, in the catchbox, and decided to keep fishing for fun but turn the fish we caught loose.

Days like that of course are rare and stunning exceptions. But with sea trout numbers increasing in the Bay and all along the Atlantic Coast every year, there's no reason not to expect the same and more this year.

No one knows exactly why sea trout are taking off, but their range has clearly expanded dramatically over the last decade. There have been so many large trout caught in Maryland waters in the last 10 years that the state has twice raised the minimum-size regulations for a citation catch, first from three to five pounds, and more recently up to seven pounds.

Commercial fisherman remember a time back in the 1930s when trout exploded similarly in the Chesapeake. Wayne Brady said weakfish came as far up as Rock Hall back then, and his uncle caught so may his first year out that he paid for his boat and fishing rig in one season.

In the 1950s, there was a large supply of sea trout in the lower. Bay, according to scientists at the Virginia Institute of Marine Science.

"We didn't understand the fluctuations of these fish very well," said Frank Wojcik of VIMS. "But we have seen a great number of juveniles in the Bay in the last few years, and the last time we had as many young of the year as we did in 1979 was way back in the middle '50s.

"We have very, very high numbers now. With the strong spawning last year, it looks very good for the future."

Sea trout have the additional advantage of not being highly desirable for commercial fisherman, so pressure on them remains moderate. They spoil quickly and the flesh has a tendency to grow soft if they are not iced promptly and kept on ice.

As a result, Brady says seafood buyers pay only about 35 cents a pound for them, compared to almost $2 a pound for striped bass.

But almost anyone with a taste for seafood agrees that a properly cared-for sea trout is high on the list of marine delicacies.

Charter skippers who will pursue trout on the Stone Ock are not particularly numerous. Most mid-Bay chartermen prefer to troll for blue fish. But there are some hard-working types willing to go for the high sport of sea trout angling.

When calling charter centers, such as ABC Charters or Manifold's Marina in Deale, Rod 'n' Reel in Chesapeake Beach or Levon Harrison's Chesapeake House across the Bay in Tilghman to arrange a full trout trip, make certain to request a skipper who is familar with and willing to go after trout.