WITHIN the next week the white perch should begin migrating up the Chesapeake to the mouth of the Susquehanna where they'll spawn. This should last until sometime in late May. By then most of the large females will have moved out to the deeper waters of the Upper Bay for most of the summer.

Everyone keeps asking, "Where are the bluefish?" The latest reports have them schooling up between Virginia Beach and Point Lookout. The Bay water temperature at the mouth of the Potomac is still a brisk 55 degrees and holding. The peak-activity temperature for bluefish is from 62 to 72 degrees. It takes only a slight warming trend to produce ideal conditions for those big chopper blues. Sharpen your hooks and fishing skills -- everything should break loose in the Chesapeake within the next two weeks.

Meanwhile, the best fishing action has been in freshwater areas of Virginia, where loads of stripers, crappies, bass and shad are being caught. WHAT'S THE CATCH? WASHINGTON AND VICINITY

POTOMAC RIVER -- Ray Fletcher at Fletcher's Boat House reports the white perch fishing is still holding up well just a few hundred yards from the docks. Grass shrimp fished on the bottom have been producing excellent catches of these tasty fish. Excellent catches of herring are also being made in the same area. Scattered catches of shad are reported, too, in this particular portion of the Potomac and the numbers seem to be increasing daily. Small shad darts cast in the fast water are the key.

Bass guide Glenn Peacock reports excellent catches of medium-sized largemouths near the 14th Street Bridges. A bit farther downriver, at the Woodrow Wilson Bridge, anglers are reporting similar catches of bass in the Spoils Area. The bass are now beginning to spawn, so please release them unharmed so there'll be lots for future generations of fishermen. MARYLAND

POTOMAC RIVER, DAM 4 -- Smallmouth fishing is still reported excellent here, with catches of two-pounders being made. Live minnows fished at the base of the dam have been a good bet. Just above the dam, in the deeper water, several larger bass have been taken by casting tiny Rebel Crawfish and working them close to shore.

TRIADELPHIA, ROCKY GORGE -- Mitchell Polan of Laurel, using a live minnow, hooked and landed a citation-size (four-pound, 10-ounce) smallmouth bass in Rocky Gorge this past week. The crappies are getting ready to spawn, and the action on them has dropped off a bit during the past few days, reports Bob Griffith, manager of Fishing and Archery Outfitters in Laurel. However, some medium-sized largemouths are still taking live minnows, crankbaits and plastic worms fished in the shallows close to shore. VIRGINIA

LAKE ANNA -- Bass and striper fishing has been sporadic since the cold front passed through. However, several good-sized stripers have been taken on the warm-water side of the lake. Bass guide Gene Hord checked in five stripers at Anna Point Marina this past week that ranged from nine to 13 pounds. Crappie fishing is holding up well near the beaver huts and under the piers. Live minnows are best for the crappies; the stripers are taking large shiners fished in somewhat deeper water. Within the next few days, the stripers should begin spawning, and fishing could be red hot. Loads of good-sized black crappies are also being caught on the cold-water side of the lake in the brush piles. Live minnows are the secret to success here.

RAPPAHANNOCK RIVER -- Carl Gentry at Chesley's Sporting Goods in Fredericksburg is still checking loads of huge catfish from the river. Although no one has topped that 33-pounder from a few weeks ago, a few have come close. If you're looking for dynamite shad fishing, the river is still producing fantastic catches of both white and hickory shad. Small shad darts cast in the fast water are highly productive. Scattered catches of good-sized smallmouths are also being made with live minnows.

JAMES RIVER -- Fantastic catches of smallmouth bass continue to dominate the action on the James River. The bass are taking live minnows fished close to the rocks, says Earl Coppage at Timberlake Sporting Goods in Lynchburg. Some jumbo crappies weighing well over a pound are also taking minnows in the same area. Fair catches of large, blue catfish are coming in some of the deeper pools; they'll also hit live minnows.

SMITH MOUNTAIN LAKE -- Striped bass fishing in the upper end of the lake continues to be red hot. Several stripers of 25 to 30 pounds have been taken this past week, reports Lacey All at All's Hunting and Fishing in Salem. They are now spawning and hitting jointed Rebel plugs cast to them near the mouths of the creeks. Some good-sized crappies are also in the same area, but angler interest has decreased because of the number of stripers being caught. The largemouth bass fishing is excellent in those same areas. Live minnows and small jigs are the top producers. CHESAPEAKE BAY

SUSQUEHANNA RIVER -- There are a few herring in the river, according to Terry Rhudy at Conowingo Bait in Darlington, which is a good indication that the shad are not far behind.

GUNPOWDER, DUNDEE RIVERS -- Some huge white perch are taking grass shrimp at the mouth of the Dundee River, according to Sue Demaf at Gunpowder Bait and Tackle in Essex. Some are running up to 14 inches and weigh more than a pound. You'll need a boat to reach the perch; the launch ramp at Gunpowder State Park is just a five-minute run from the fish.

UPPER BAY -- The tidal ponds at Bellgrove Road are still producing good catches of catfish, white perch and an occasional largemouth. Grass shrimp have been the ticket to success for the perch while the catfish are taking bottom-fished nightcrawlers or bloodworms. When the peeler crabs become available, catfish catches will improve substantially.

BAY BRIDGE AREA -- The upper end of the Magothy River has really come on strong for the perch, reports "Fishing Charlie Ebersberger" at the Angler's Sport Center in Annapolis, but you'll need a boat and a good depth finder to locate the larger fish. The big guys are hanging in the deeper holes and hitting grass shrimp fished on the bottom. Bloodworms are also taking a few fish in those same areas.

CHESAPEAKE BEACH -- The Rod N Reel Dock will be holding its fourth annual pro-am bluefish tournament in the Middle Bay on May 3rd and 4th. Cost of entering is $50 per day for a private boat; $100 per day for a charter captain. Registration deadline is May 2; send entries to Captain Shaker Black, Rod N Reel Dock, P.O. Box 98, Chesapeake Beach, Md. 20732. Prizes total $10,000, with $5,000 of that going for the heaviest blue. For more information, call Black at 301/257-2191.

CHOPTANK RIVER -- The perch fishing has really taken off during the past few days. Keith Turner at Tommy's Sporting Goods in Cambridge reports grass shrimp and bloodworms fished from the U.S. 50 bridge are bringing perch up to 13 inches. Several pan-sized stripers are also in the same area, but they must be released because of the striped bass moratorium.

SOLOMONS ISLAND -- Judging by the number of large sea trout being caught in the nets in Virginia, the run should be excellent again this season near the mouth of the Patuxent River. Although there's no telling when they'll arive, you might be keep in mind last year's success of Captain Bill Meadows on the El Toro. He produced fantastic early-season catches of weaks using a custom-made bucktail tied with yellow deer hair on a pink head. This particular lure produced big trout when all others seemed to fail.

CAPE CHARLES -- A few black drum are now showing up in the nets near the bridge tunnel, according to Kings Creek Marina in Cape Charles. In addition, huge chopper blues are beginning to break during the late afternoon hours. The water temperature here is now hovering near the 60-degree mark, which means bluefish activity could be red hot over the weekend. Captain Otis Asal on the Bucaneer figures you'll be able to take all the blues you can handle within the next few days. Captain Monty Webb at Eastern Shore Safaris is now booking parties for drum fishing. ATLANTIC OCEAN

OCEAN CITY -- Those massive schools of mackerel are continuing to migrate north and are now concentrated between Ocean City and Cape May. However, the "macks" are getting closer to shore and on calm days are within range of smaller boats. Several charter captains along the coast report outstanding catches within 10 miles or less of the beach. CHINCOTEAGUE, WACHAPREAGUE -- Although there are still a few schools of mackerel here, the big news is that the flounder have begun migrating into the shallows of both areas. Early-run flounders are usually larger, and there are reports that scattered catches of three- to five-pounders are now being made by drifting live minnows and squid strips on the bottom. With the next few days, catches should improve if the water gets warmer.

VIRGINIA BEACH -- Excellent catches of big blues are now being made in the surf by anglers casting large surface plugs and cut bait. Although the average blue is around 14 pounds, several choppers of more than 19 pounds have been taken recently.