LAST weekend's cold front had a fantastic effect on fishing. Nearly every species reacted by heading for the warmer water in the shallows, making themselves accessible to anyone with a fishing rod.

Most of the lakes in Virginia are reporting excellent catches of huge striped bass in the shallows near the mouths of the creeks. In addition, lots of largemouth bass are in these same areas.

The farm ponds on Maryland's Eastern Shore are also a good bet for some dandy largemouths. This can be attested to by Larry Andrews of Lanham, who landed a chunky, 23-inch bass of eight pounds, five ounces in a Chestertown farm pond.

Crappie spawning activity is at its peak, so the fishing for them should be excellent during the next several weeks.

Saltwater anglers will be happy to know those big blues have invaded the shores of the lower Chesapeake. At Cape Charles last weekend, several huge bluefish were caught at the southern end of the Chesapeake Bay Bridge Tunnel. The choppers weighed in the neighborhood of 15 to 18 pounds, whichmeans a real tussle on any kind of fishing gear. The mackerel are still lingering just off the coast and should remain with us for the next week or two. Most charter boats report catching all you can handle. WHAT'S THE CATCH? WASHINGTON AND VICINITY

POTOMAC RIVER -- The white perch fishing is still outstanding at Fletchers Landing, according to Ray Fletcher. Fletcher says there are also a few bass being caught, but he emphasizes that the largemouths are now spawning and should be released to ensure future fishing. Bloodworms and grass shrimp fished on the bottom are the best bet for the perch, while the largemouths are taking live minnows and some crankbaits. Good concentrations of catfish are also showing up in the same area along with a fair number of herring. With luck, there'll be some shad in the river within the next week or two. MARYLAND

POTOMAC RIVER, DAM #4 -- Good ches of smallmouth bass are now being made on the upper reaches of the Potomac above Dam #4. Although these aren't the huge bronzebacks that eat fishing tackle, several have tipped the scales at 3 pounds. Large, live minnows and crayfish are the ticket to success here.

INDIAN HEAD -- If you're looking for a real battle on light tackle, some huge carp are spawning in the Potomac near Indian Head. One Baltimore resident ventured there with his newly acquired $16 dollar rod-and-reel combo and returned to Clyde's Tackle Shop in Baltimore with a whopping 30-pound carp that inhaled a nightcrawler. The angler said he fought the fish for nearly an hour before beaching it.

TRIADELPHIA, ROCKY GORGE -- Bob Griffith at Fishing and Archery Outfitters in Laurel reports fishing is excellent in these Washington Suburban Sanitary Commission lakes. Large northern pike are taking live shiners in "The Gorge," says Griffith, and both lakes are producing lots of good-sized crappies. In addition, good catches of largemouth bass are being made by anglers fishing with jigs trimmed with live minnows or pork rind, Rebel Crayfish and Bomber Crayfish. The water condition is excellent at both lakes for this time of year.

COLUMBIA LAKES -- Crappie are now on their spawning beds and the fishing is reportededly excellent in the lakes of Columbia. However, most of these fish are on the small side and only about 20 percent are worth keeping. Stocked rainbow trout continue to please local youngsters who go fishing after school. Live minnows have been the best bait for the crappies, while the trout are taking small, pea-sized chunks of Velveeta cheese. VIRGINIA

LAKE ANNA -- Crappie fishing continues to hold up well in this nearby Virginia impoundment as does the largemouth bass fishing. Pete Sprague at Lake Anna Sporting Goods reports loads of medium- to large-sized crappies are being caught close to the piers and beaver huts. Scattered catches of largemouth bass are also reported in those same areas. Live minnows have been best for the crappies; the bass are hitting on small crankbaits, live minnows and small jigs trimmed with a chunk of pork rind. Within the next few weeks, the stripers should begin to migrate into the shallows where they'll become prime targets.

RAPPAHANNOCK RIVER -- Spring has come early to this northern Virginia river, and, according to Carl Gentry at Chesley's Sporting Goods in Fredericksburg, the fishing has been outstanding. Roger Summers of Fredericksburg managed to hook up with a huge smallmouth of 5 1/2 pounds. He was using a live minnow.

Anglers casting small shad darts and gold spoons are getting into some exciting shad action. Gordon Stillman of Fredericksburg checked in a 6-pound, 5-ounce hickory shad he caught using that combination. A potential Virginia state record catfish was taken in the same area by Bobbie Noblin of Fredericksburg; it weighed in at a whopping 33 pounds, 12 ounces.

SMITH MOUNTAIN LAKE -- The stripers have really come on strong within the past two weeks, reports Lacey All at All's Hunting and Fishing in Salem. Topwater plugs and white bucktails trimmed with a chartreuse grub have accounted for fantastic catches of striped bass weighing up to 30 pounds. The stripers have migrated to the upper reaches of the lake to spawn and are concentrated in shallow water near the mouths of the creeks. Most boats working the area report catches of up to a dozen fish per boat. Mixed with the stripers are some dandy largemouths weighing up 5 or more pounds and they are now on their spawning beds. Crappie fishing continues to be good in the lower end of the lake where live minnows and small jigs are managing to fill stringers. The striper and bass action should continue for several more weeks, and then you'll have to fish deeper to catch them.

JAMES RIVER -- Several smallmouth bass weighing more than four pounds were taken from the river last weekend on large shiners fished in the fast water. Anglers at the Carvin's Cove Lake in Salem report catching lots of good-sized crappies, and a few white bass are now migrating into the same area. The white bass are tough fighters and can reach five or more pounds. However, the average weight is closer to two pounds. Live minnows will take both species. CHESAPEAKE BAY MARYLAND PORTION

BAY BRIDGE AREA -- The white perch have migrated into the upper Magothy River, reports "Fishin' Charlie" Ebersberger at the Angler's Sport Center in Annapolis. However, you'll need a boat to reach them. Within the next few days they should move into the creeks to spawn. Live minnows and grass shrimp have been the most productive bait. Several large bass have also been checked in during the past few days, says Charlie, with the largest weighing a little over 8 pounds.

PATUXENT RIVER -- The white perch have moved into Allens Fresh to replace the yellow perch. Large white perch are now being caught in this shallow creek by anglers using grass shrimp and bloodworms fished on the bottom, according to folks at The Tackle Box in Lexington Park. Some of the local farm ponds bordering the river are now producing some huge crappies of up to 2 pounds. Live minnows lip-hooked to the back end of small shad darts have been productive. An 8-pound, 10-ounce largemouth was caught in Saint Mary's Lake by Henry Camp of Hollywood, Maryland. The lunker hit a small crankbait fished close to shore.

POINT LOOKOUT -- Although no blues have been caught by hook and line at the mouth of the Potomac, several huge choppers have shown up in the pound nets used to catch menhaden. Apparently, the blues chased the fleeing menhaden into the nets and couldn't find their way out. Within the next week or two at most, the water will be swarming with these early-season giants which will take cut bait fished in a chum slick of ground menhaden.

CHOPTANK RIVER -- Lots of medium-sized white perch are still being caught at Red Bridges in the upper end of the river, according to Tommy's Sporting Goods in Cambridge. The perch will soon scatter to deep water areas when their spawning is complete. This should happen in the next week or two. CHESAPEAKE BAY VIRGINIA PORTION

CAPE CHARLES -- Captain Otis Asal on the Bucaneer ventured out less than a mile from the town of Cape Charles this past week with his fishing party. By the end of the day, they had 18 good-sized tau-tog and one 3-foot dog shark. Within the next week, some huge blues should move into the shallows near this area, and they will take surface plugs cast in the shallows. The fishing here is fantastic throughout the entire season. ATLANTIC COAST

OCEAN CITY -- The bulk of the mackerel fishing is 10 to 12 miles out from the inlet, says Captain Colman Bunting at Ocean City. On a good day, you can fill every cooler on the boat in less than two hours. But, if the weather is rough, which it sometimes is during April, you'll have to work harder for half that amount. Mackerel trees, weighted with a Diamond Jig have been highly effective.

CHINCOTEAGUE -- Several of the charter boats are now fast into those huge schools of mackerel. If the weather remains reasonably stable, these fish will stick around for at least another two weeks. However, a quick warming trend will send them scurrying north.

DELAWARE BAY -- Captain H.D. Parsons at the Fisherman's Wharf in Lewes, Delaware, reports the mackerel fishing has been fantastic. Parsons also says he expects to see an early run of larger-than-normal sea trout this season due in part to the mild winter and the large number of weakfish caught along the coast last fall. The trout usually arrive in late April or early May, depending on weather conditions -- the cooler the later.