THE SHAD could use a little understanding.

It is a fish so complicated that the whole is worth less than the sum of its parts; that half a shad can cost more than a whole shad. You see, the fish has a fatal flaw and a fatal asset.

The flaw is bones -- a bone structures so intricate that it can take two years for a professional to learn how to bone it properly and 10 minutes to bone each fish once he knows how.

The asset is roe -- beef-colored lobes that turn gray on cooking, closely packed with eggs the size of semolina grains. The roe is considered a delicacy, albeit a bland and potentially dry delicacy, that some think has the single virtue of being boneless. Others buy a whole shad just for the roe, and throw away the rest.

In any case, shad is an early and sure sign of spring, for it is one of the few foods left in the world that can be obtained fresh only in its season. Shad migrate from the sea to coastal rivers and streams, along the Atlantic coast from Florida to Newfoundland, and are known (as alose ) in France as well. In New England they have named a plant after this fish -- the shad bush, which announces the coming of shad season with its white blossoms. And now, like wines and caviar, shad have been transplanted to America's Pacific coast, where they will probably spawn shad-tastings on several continents to determine whether the upstarts compare with their traditional counterparts.

What's all the fuss about? The shad, of the herring family, is a fatty fish, not so fatty as the cod of haddock, but over eight times as fatty as the flounder. And networks of bones crisscross it in such a way that eating unboned shad is a daredevil experience, and hardly anybody learns how to bone it professionally anymore. Bob Jordan, of Baltimore's Lou Foehrkold seafood company, tried to learn on his own when he worked at Chevy Chase Seafood; yet after he started apprenticing to Foehrkold, it still took him 1 1/2 years. Three men working for 3 1/2 to four hours can only bone 60 fish; but then, said Jordan, "We bone each fish like we are going to eat it ourselves." Shad boners, like any other craftsmen, vary in their ability and the care they take, so even some boneless shad will be found to have bones. Jordan estimates that 95 percent of the boned shad in Washington comes from Baltimore, either from Foehrkold's small operation -- which now sells almost exclusively to Chevy Chase Seafood and the Fishery -- or from Seacoast Seafood, a much larger operation.

Because shad has become so popular, the market is tight, even though seafood store in Washington sell boned fillets for $3.99 (Giant) to $6.69 (Neam's) a pound, and sets of roe -- which serve one roe lover or two neutral dinners -- for $1.59 (Giant) to $7 (Neam's) apiece. Whole unboned shad is, so far this season, difficult to obtain at all, and last week was selling at 99 cents to $2.29 a pound. The season has started late this year; Giant has just begun to stock shad, and at last check, Safeway had none yet.

Despite its fat content, shad is a fish with a delicate, distinctive flavor and, when cooked properly, is fragile and soft, yet meaty. In other words, there is nothing else like it. And once you are enamored of it you can accept no substitutes but just wait hungrily 10 months a year for the shad to run again.

Before boning the fish, one must let it firm for two or three days, for when very fresh the flesh tears easily. Thus, once you have it at home, it is likely to already be several days old, so you should not attempt to keep it more than two or three days before cooking it. That is not problem for people who have gone to such lengths to get their hands on some. Shad range in size from about 1 1/2 to eight pounds, but most of those on the market are four pounds or less. Chevy Chase Seafood reports that 95 percent of its customers who buy shad are shad lovers returning for more. For them, a half-pound boneless shad per person is not too much fish, or 3/4 pound, if it is unboned.

Just as there are people who love the roe but never eat the fish, and vice versa, there are people who insist that there is only one way to cook shad, and others who would not deign to eat it that way and counterattack with their own. The lines are firmly drawn between long-cooking and short-cooking.

Long-cooking, which some consider akin to biting off your nose to spite your face, was devised as a way of melting the bones -- defanging the fish, so to speak. The whole fish is baked, either sealed in foil or basted with lemon and water as it cooks on a rack, at 250 degrees for five hours. The bones soften like the bones in canned salmon. But who would want to turn fresh salmon into canned salmon?

There. I have revealed my prejudice. It is for shad quickly and lightly cooked, brushed with butter and chopped shallots, broiled skin-side down for less than 10 minutes, perhaps basted with a little white wine. It should not be turned. It should be seasoned with lemon or glazed with cream or sauced with beurre blanc , that sumptuous French white butter sauce. It can be lightly floured before cooking.

Nearly as delicious is baked shad, and in baking there are more options. It can be stuffed or not, floured or not, basted with lemon or vinegar or white wine, or even spread with mayonnaise before baking at 400 degrees, it can be baked for 20 minutes split, 30 minutes whole unstuffed, 35 minutes stuffed. And then you eat it carefully, picking out the bones as you go along, and enjoying it all the more for the work it involves -- as one might with steamed crabs.

The roe, like everything else, occasions two schools of thought. Some blanch it and then saute it, others just saute it. Some flour it, others don't. Either way, it takes 12 to 20 minutes to saute in butter over low heat, turning once, and you can add parsley and shallots as it cooks, lemon afterwards. Just because it has no bones, don't consider it totally safe. Shad roe pops in the cooking, spurting hot grease at you if you don't take care. So pierce it a few times before cooking, and cover the pan to protect yourself. Many people like shad roe with bacon. But then, many people like shad roe for breakfast.

Who can blame them? Thomas Jefferson, it is said, used to have barrels full of live shad brought to Monticello to stock his pond.But the rest of us are more limited in what we can get and when we can get it, and have to take advantage of any shad-eating opportunity we can find. SHAD AND ROE IN ANCHOVY CREAM (2 servings) 1 shad fillet White pepper to taste 2 tablespoons butter 1 pai shad roe 1 tablespoon finely minced shallots 3/4 cup heavy cream 2 anchovy fillets, chopped Lemon juice to taste Chopped parsley for garnish

Sprinke shad fillet with pepper. Melt butter in skillet large enough to hold shad and roe. Add shallots and arrange shad and roe in pan. Pour in cream and bring to boil. Lower heat to a simmer, cover and cook for 10 to 15 minutes. Carefully remove shad and roe to a platter. Add anchovies to cream and boil down to thicken cream, stirring constantly.Squeeze in lemon juice to taste and pour over shad and roe. Sprinkle with parsley and serve immediately.

Note: Instead of anchovy, 1 teaspoon chopped fresh herb such as mint or basil can be added. Salt will be necessary if anchovies are omitted. ORLEANS SHAD (2 servings) 1 tablespoon oil 4 teaspoons minced shallot 1 teaspoon minced parsley 1 small garlic clove, minced 2 tablespoons chopped ham 1 teaspoon dijon mustard 1 fillet shad Salt and pepper to taste 2 tablespoons butter 1 to 2 teaspoons flour (optional) Lemon for garnish

Heat oil in a small pan. Add shallot, parsley, parsley, garlic and ham, and saute 2 to 3 minutes, until lightly browned. Stir in mustard. Put shad, skin side down, in a lightly oiled baking pan, lined with foil if desired. Spread ham mixture over fish. Sprinkle with salt and pepper. Dot with butter. Sprinkle on a fine layer of flour, if desired. Bake at 400 degrees for 20 minutes, basting once or twice with the butter that accumulates in the pan. Serve immediately, garnished with lemon. MARYLAND STUFFED SHAD ROE (4 servings) 2 pairs shad roe 6 tablespoons butter 2 tablespoons flour 1 cup light or heavy cream Salt and pepper to taste Pinch of nutmeg 1/2 pound lump crabmeat

Saute shad roe slowly in 4 tablespoons butter, covered, until completely cooked through. Turn halfway through cooking. In the meantime, melt 2 tablespoons butter in a small saucepan. Add flour and cook, stirring, over low heat without browning, for 3 minutes. Gradually stir in cream, bring to a boil, stirring continuously, and simmer for a few minutes while roe cook. Season cream sauce with salt, pepper and nutmeg, and gently stir in crabmeat. Remove roe from pan and split each roe, being careful to leave it hinged. Cover with crabmeat mixture. Pour over it the browned butter from the shad roe pan and serve. MARK CARALUZZI'S SHAD GRAVLAX (8 servings as an hor d'oeuvre) 2 tablespoons kosher salt 1 tablespoon sugar 1 1/2 teaspoons freshly ground pepper 2 boneless shad fillets, totaling 1 pound 1 bunch dill

Mix salt, sugar and pepper, and rub into the flesh side of each fillet. Coarsely chop half the dill and spread it on the seasoned flesh side of one fillet. Top with the other fillet, seasoned flesh side down, to make a sandwich. Line the bottom of a rectangular casserole with branches of dill, reserving enough to chop 3 tablespoons for the sauce. Place closed fish sandwich on dill branches and weight with a board, a pan, or a plate topped with 1 or 2 pounds of canned goods to keep the fish tightly compressed.Allow to marinate under refrigeration 14 to 48 hours, turning as frequently as possible but at least 3 times. To serve, open fish and scrape off seasonings with a knife. Remove fillets from skin and cut diagonally into bite-size pieces.Arrange on a platter, garnish with dill branches from the casserole, and serve with mustard sauce. MUSTARD SAUCE (Makes about 1 cup) 4 tablespoons creole or German mustard 1 1/2 tablespoons sugar 2 tablespoons white wine vinegar 1/3 cup olive oil 3 tablespoons chopped dill (reserved from gravlax recipe)

Stir and serve with gravlax. DOROTHY FOEHRKOLD'S MAPLE SHAD (2 servings) 1 shad fillet 1/2 cup apple cider vinegar 1/4 cup maple syrup 2 tablespoons worcestershire sauce Salt and pepper to taste

Wash shad and place in broiler pan, skin side down. Mix vinegar, maple syrup, worcestershire, salt and pepper, and pour over shad. Broil 10 to 20 minutes until well browned, basting 3 times. Serve immediately. GERARD VETTRAINO'S SHAD ROE (From Jean-Pierre Restaurant) (4 servings) Marinating and cooking roe: Juice of 1 lemon Freshly ground pepper to taste Olive oil to cover roe 4 pairs shad roe

Combine lemon, pepper and oil. Marinate roe in the mixture at least 12

Combine lemon, pepper and oil. Marinate roe in the mixture at least 12 hours. Drain roe and cook at 400 degrees for 5 minutes or until done. Granishes: Monegasque: Olive oil to cover bottom of pan 2 tomatoes, sliced thinly 1 large eggplant, sliced thinly 2 large zucchini, sliced thinly Salt and pepper to taste

Heat olive oil in baking pan, add vegetables, season with salt and pepper, and cook covered in a 400-degree oven for 15 minutes. Anchovy Butter: 8 flat anchovy fillets 1/4 pound unsalted butter Juice of 1/2 lemon

Combine ingredients in a blender until smooth.

Assemble:

Arrange cooked vegetables on a plate, top with roe, then with anchovy butter. Serve. SHAD ROE POLONAISE (2 servings) 2 pairs shad roe 1/4 cup butter 2 tablespoons chopped shallots 2 tablespoons bread crumbs 2 tablespoons chopped parsley 2 hard-cooked eggs, chopped 4 teaspoons lemon juice Salt and pepper to taste

Cook shad roe in butter, covered, 10 to 15 minutes, until cooked through, turning once. Transfer to a hot platter. Add shallots to butter in pan, and saute 1 or 2 minutes over moderate heat, until softened. Add bread crumbs and cook 1 more minute. Add rest of ingredients, then salt and pepper to taste. Heat through, pour over roe and serve. SHAD ROE SALAD (4 servings) 1 cup cooked shad roe 1 tablespoon lemon juice 1 cup seeded, diced cucumber 1/4 cup mayonnaise 1/8 teaspoon ground celery seed 1 to 2 tablespoons capers Salt and pepper to taste Lettuce leaves and hard-cooked eggs for garnish

Mash roe well. Stir in lemon, cucumbers, mayonnaise, celery seed and capers. Salt and pepper to taste. Serve on lettuce leaves, garnished with hard-cooked eggs. Flavor improves if the salad is made ahead and refrigerated to let flavors blend.