The behemoth of a bluefish didn't seem to know it was hooked.

It had been swimming happily in the chum slick behind the boat on this calm, warm morning, gobbling up chunks of ground menhaden as they rolled along on the tide. The plump piece with the hook in it was just another morsel.

With the barb imbedded in the corner of its mouth, the blue swam off lazily, tugging against the drag. You don't stop a fish like that. With 12-pound test line and a 16 1/2-pound blue, the fish makes the rules.

Three other lines streamed behind the boat, glinting in the sun. In one sweep, the blue swam across the nearest two, then back under them, creating havoc.

Manuel Munoz-Carrasco set his rod down and jumped to work clearing up the mess. Whenever the blue stopped, I reeled in. Munoz gathered the fouled lines as they surfaced and analyzed which went over what, directing me to hand my rod over one and under another until the kinks came out.

He worked quickly and it was a good thing, because almost the moment he had the last tangle cleared, his rod went down hard with an 11-pounder.

The fun began. "I wish I could get a picture of this," said Gary the cameraman as Munoz and I danced around the stern, passing rods over each other's heads and under each other's arms, climbing over the engine box of Billy Brener's 25-footer, Chum King, moving from one side of the boat to the other to accommodate the powerful runs of the fish.

Ah, May!

In no other season does the Chesapeake offer fishing like this.

A few years ago the allure of May in the bay was huge rockfish (striped bass) of 40 pounds and up, on their way up the Chesapeake to spawn.

But the decline of rockfish and Maryland's ban on fishing for them halted that sport. Nowadays the May attraction is big blues and, happily, nothing seems to be going wrong with them.

Blues have grown so plentiful along the East Coast for the last decade, "You'd have to be the village idiot not to catch them" in the height of the season, said Stuart Wilk, bluefish specialist for the National Marine Fisheries Service.

Five or six years ago, Wilk was saying the abundance couldn't go on forever, and he still says that, though not quite as convincingly. "So far," he conceded the other day, "it's just been up and up and up since the 1970s."

Hereabouts, the biggest blues arrive first as seagoing monsters up to 20 pounds cruise through the Chesapeake on their way north to New England.

The bluefish chase menhaden and river herring into the bay, then move out to sea again as water temperatures rise.

Behind them come smaller blues in the two- to six-pound range. As summer progresses, blues seem to get smaller and ever more numerous, until by October you can catch half-pound snappers by the bushel basket.

Spring is when you stand a chance of catching the biggest bluefish you ever saw, but it's also when you risk catching nothing at all. Big blues are the least plentiful, it stands to reason, and most professional charter skippers consider it a good day if they come back to the dock with one per customer.

We had almost that many. Back in port, Gary the cameraman had Billy the captain perch on the cleaning table to pose with the 16 1/2-pounder.

On a boat tied up nearby, a woman laughed out loud. "That's the first time I ever saw a fish so big," said she, "that a grown man had to sit down to hold it."

Bay charter captains are gearing up for the annual early-season run of big bluefish. Chopper blues already have been caught from Point Lookout on up to the Bay Bridge, but generally the fishing is better in the lower bay first, and improves up the bay as the month progresses.

To book a charter, you might call Scheible's in Ridge, Md. (Point Lookout area); Associated Bay Captains in Deale; the Rod 'n' Reel dock in Chesapeake Beach or Harrison's Chesapeake House in Tilghman Island on the Eastern Shore.

Generally, charter boats carry six people and charge $225 to $300 a day. Scheible's also offers headboat fishing for blues on the 60-foot Bay King at $25 per person.

Charter operators in the Deale, Tilghman and Chesapeake Beach areas generally troll for blues using heavy tackle; skippers around Point Lookout favor chumming and use lighter tackle.

Small-boat fishermen who chase big blues on their own usually troll in deep water around the main shipping channel, using large spoons suspended at depths of 10 to 30 feet.

Also in May, big blues often go into the shallows in early morning and late evening to feed on menhaden. Perhaps the height of sportfishing on the bay is casting topwater lures to these fish, which are sometimes caught on Hackett's Bar just below the Bay Bridge, around Matapeake on Kent Island and along the shores of the lower Choptank River, to name a few popular spots.

If you just want to see a big bluefish, you might stop by the Rod 'n' Reel dock in Chesapeake Beach tonight around 7 o'clock, when some 200 boats in the spring bluefish derby will be weighing in their catches.