If I could only fish offshore in south Florida during one month of the year, I would choose to fish in April. Although sailfish season is tapering off, some spindlebeaks are still around. Dolphin are becoming more numerous, kingfish and wahoo are present, jumbo bluefish migrate through our area (and are prime targets for flyrodders), and an occasional giant bluefin tuna inhales an unsuspecting angler's bait, often emptying the reel of line before the fisherman realizes what has happened.

Still, the reason I most enjoy April fishing is that the month usually signals the arrival of one of the world's premier big-game fishes to our local waters: the blue marlin.

Blue marlin, Makaira Nigricans, can be found fairly close to shore off the Palm Beaches during the spring, summer and early fall. The current I.G.F.A. all-tackle record for Atlantic blue marlin is 1,282 pounds, while the largest Pacific blue that I.G.F.A. recognizes is 1,376 pounds. Much larger blue marlin have been taken in the Pacific, although they haven't been caught according to I.G.F.A. regulations and thus don't appear in the record books. Many big-game anglers and ichthyologists believe that blue marlin weighing over a ton are prowling the world's oceans, and that it is just a matter of time before one of these behemoths is landed.

Blue marlin can be caught by any of several methods. The classic technique involves trolling rigged dead baits such as mullet or mackerel. Properly rigging dead baits so they skip or swim enticingly is an art in itself. Many books and magazine articles illustrate how to prepare marlin baits, but it's most helpful to seek out an "old pro" at a tackle shop or marina and learn first-hand.

An extremely popular method in some areas is trolling large artificial lures ("plastics") at relatively high speeds of 8 to 12 knots. Again, properly rigging the lures requires a certain amount of skill, and there is considerable debate as to what the best rigging method is: two hooks stiff-rigged at 90 or 180 degrees, a free-swinging rear hook, semi-stiff rigging, or a single hook.

While single-strand wire leaders are usually used for rigging dead natural baits, monofilament leaders testing 300 to 400 pounds are normal when fishing artificials. Monofilament has some definite advantages for marlin fishing — it doesn't kink like single-strand wire; is less visible to leader-shy fish, and makes it easier to "wire" a fish when it's close to the boats. Due to its flexibility, it also allows lures to perform better than they would on heavy wire. An occasional fish may fray through the mono, and wahoo will sometimes clip off lures or hooks, but monofilament's advantages outweigh its disadvantages.

Offshore of the Palm Beaches, the most popular and successful way of catching blue marlin involves slowly trolling live baits on 50- to 80-pound class tackle. While marlin are often caught in deeper water and, on occasion, in shallower water, depths of 150 to 300 feet appear to be the most productive in our area.

The standard live-bait rig used locally consists of a sharpened 12/0 to 14/0 Mustad 7731 or similar hook secured to 10 to 15 feet of monofilament or single-strand wire leader. A small hook (6/0 to 7/0), usually with a short shank, is attached to the bend of the large hook with either a split ring or short (1- to 3-inch) piece of No. 6 to 9 single-strand wire.

When a live bait such as a little tunny (incorrectly called bonito locally) or rainbow runner is caught, it is quickly unhooked and the small hook on the live-bait rig is inserted in its upper jaw. If the hook is placed in the lower jaw, the bait's mouth will be forced shut when it is trolled, and the bait will quickly suffocate. This method is faster than eye-rigging baits as is done in Hawaii and elsewhere, and the large hook still remains in front of the bait's head where it is unemcumbered during the strike. The bait must be returned to the water as quickly as possible to ensure that it stays lively.

Two such baits are usually fished at one time: one fairly close to the boat, and one farther back. Some captains leave their reels in gear while trolling, and throw the reels into free-spool when a marlin strikes. Others leave the reels in free-spool, and have a mate hold the line. When the marlin strikes, the mate releases the line and thumbs the reel's spool to prevent a backlash.

The method I prefer with lever-drag reels such as Penn Internationals and Shimano TTS' is to advance the reel's drag lever just past the point where the reel will not backlash when line is yanked from the spool. This is still a fairly loose drag adjustment, and well below the reel's "strike" setting. I attach a large snap swivel or tag-line clip to a transom cleat with a foot or so of heavy monofilament. I then wrap a No. 64 heavy rubber band around the line at least eight times (the more wraps, the better), and put the two loops at the ends of the rubber band through the clip/snap swivel. That's it! The rubber band is strong enough to resist breaking from the pull of the bait, but when a marlin strikes, the rubber band breaks and the reel releases line without backlashing or putting too much tension on the line. The angler then has time to transfer the rod to the fighting chair and strap in if a harness is available, before pushing the drag lever to "strike" and setting the hook.

While this technique works exceedingly well for blue marlin, it works even better for "brown marlin" — a local name given to sharks, which often beat marlin to the baits. Don't get discouraged if you start losing baits to sharks. Try moving into a little deeper water, outside of the bonito schools that abound in our waters during the summer months. Sooner or later, the fish you are looking for will find your bait.

I should mention one other thing. Remember that it is now illegal to sell Atlantic blue marlin in Florida (or the other 49 states, for that matter), or to kill Atlantic blue marlin with a lower jaw/fork length of less than 86 inches. Personally, I would much rather release a hard-fighting marlin than see its dried-out-carcass on a dock attracting flies. These superb animals have been overexploited in recent years, but if anglers who fish for them practice conservation by photographing their fish and then releasing rather than killing them, blue marlin will still be around for a long time to come.