NEXT MONTH SHOULD SEE the climax of the battle to stop hunters from clubbing white baby seals to death on the iceflows of the North Atlantic. October will be decisive in the 400-year history of the Canadian harp seal hunt for everyone involved -- sealers, protesters, fur buyers and politicians on both sides of the Atlantic. It may also create a rift between Canada and the nations of the European Economic Community.

A decision in October, postponed from last March for insufficient evidence, will determine whether the EEC Council of Ministers has the basis to recommend a Common Market ban on the import of pelts from young harp and hooded seals. These pelts are the chief products of the Canadian hunt, and Europe is the principal customer.

If the market disappears, the sealers will have little choice but to stay home, as many were forced to do last spring for lack of sealskin buyers. The halt of the harp seal hunt would be a major victory for several protest organizations that have directed their resources to this end for years, including Greenpeace, Fund for Animals, and International Fund for Animal Welfare.

The Canadian government claims that the EEC, in considering the ban, has ignored responsible Canadian management of the hunt which includes close regulation of killing practices and of quotas. In fact, the Canadians charge that the EEC is being guided by emotionalism and hypocritical "morality." Canada threatens (still unofficially) to retaliate.

It has a big stick through the fishing quotas it assigns EEC nations: some of the world's great fishing grounds, including Grand Banks and Hamilton Bank, fall within Canada's 200-mile waters.

Few activities have generated such targeted emotion as the annual harvest -- or slaughter, depending on which side of the argument you come down on -- of harp seals off the coasts of northern Newfoundland and southern Qu,ebec. (The hunt for hooded seals is less an issue because it is a smaller effort.)

Harp seals, named for a pattern like an Irish harp on the backs of adults, are migratory marine mammals that give birth each spring on ice floes that pass the coastal fishing communities.

Hunting the seals -- from fishing boats with four-or five-man crews, or from ships with about 30 sealers -- has for centuries been part of the work/survival cycle of the region. Harbors here freeze for half the year, making conventional fishing impossible from about November through April, so that sealing furnishes a substantial part of a fisherman's livelihood.

In the rocky, sea-blown ports, there are few other options. When the cod runs are poor, as they have been in some of these areas during the last three seasons, fishermen can derive up to half their annual income from the sale of seal fur and fat. Seal meat, fresh and home-canned, furnishes a diet staple.

Last spring, the threat of an EEC ban so depressed the sealskin market that most fishermen dared not risk expensive fuel to take their boats into the ice for the seals. They hoped for good cod runs this summer. The cod never came. Many of the men in places like Twillingate and Fogo are now close to losing their boats.

As seen by the protest organizations, the objectionable features of the Canadian seal hunt are fourfold:

Cruelty. The sealers kill by clubbing the seals on the head and sometimes, it is charged, skin them before they are dead.

Immorality. About 75 percent of the harp seals taken are young of the year, with nursing pups often killed in front of their dams.

Threat to the stocks. Some 180,000 harp seals die yearly.

Futility. With furs and oils able to be synthesized, no seal products are deemed necessary.

Canada, on the defensive for years, has been at considerable pains to police and manage the hunt into respectability. It claims that no other marine mammal is now better documented and understood than the harp seal, and that the hunt for them is the best-regulated outdoor abattoir in the world.

Regarding specific charges:

The Canadians deny that any seal is ever skinned while alive, and point out that a well- aimed blow to the seal's head results in complete brain damage and a near-instant kill. Biologists and humane societies on both sides of the issue confirm this.

The sealers are expected to deliver three blows, then to cut an artery in the chest, before skinning the seal. Fishery officers who travel with each ship check out each sealer before the hunt begins and routinely wander the ice observing, as well as inspecting skulls on the carcasses to make sure they are properly crushed. (I have seen this often enough to confirm it.) They have the authority to revoke a sealer's license.

Harp seal pups are lovely creatures. They are available, and taken, in greatest abundance as "whitecoats": newborn and helpless while nursing between the ages of 5 and about 18 days. At this point they have a commercially desirable white fur which soon after mottles and turns grey, and a thick layer of fat accumulated through nursing. The meat of the young is also the most tender and flavorful, as is the lamb and veal of more accepted animal kills.

According to seal biologists, one adult female is worth four pups or more to the herd, since she has an annual bearing potential of more than two decades. The dam abandons her pup permanently after nursing it for 21/2 weeks. The Canadians point out that this brief attachment in a lifespan of up to 35 years cannot realistically be protrayed in human terms as the protest groups do.

My own experience includes observing several hundred kills during the harp seal hunts of 1979 and 1982. (I was allowed to attend because I was both a writer and a sometime commercial fisherman.) I pitched in on the ice, helping to haul pelts, and thus in time the sealers -- who were busy at cold, hard, unpleasant work -- forgot that I was an outsider.

I saw ugly enough sights. None, however, were any bloodier -- or produced even as much animal anxiety -- as steer and pig killings I have witnessed in U.S. abattoirs.

The initial blow to the head appears to kill the seal quickly, with no hint of remaining life by the third blow and subsequent bleeding. I saw no evidence, ever, of a seal being skinned alive.

Occasionally, under supervision, I helped with the skinning myself. Some of the carcasses would twitch, even jerk. This was not pleasant for a novice, but it was reminiscent of my wide-eyed sighting, years ago in my grandmother's barnyard, of a dancing, decapitated chicken. Biologists confirm that in both cases, involuntary muscle spasms continue after death.

As for the relationship between pup and dam: there seldom appears to be any. Most pups are already alone, while most dams remaining with their pups disappeared quickly through holes in the ice. Approximately one dam in a 100 stayed to challenge the sealers. About half of these were killed with their pups. (Canadian law permits killing a female at whelping time only if she is "belligerent.") Other times, the sealers spared both dam and pup, usually with an appreciative laugh at her grit.

While the European Economic Community debated its resolution against Canadian seal products, a report gave the delegates pause. The respected International Council for the Exploration of the Sea (ICES), an independent body of marine-resources experts whose research and advice is supported by 18 member governments, declared in November 1982 that the Canadian harp seal hunt was humane.

Further, it found that the harp seal population has been increasing steadily, rather than declining under too large a kill quota as charged by the protesters. Allowing margins of error for counting creatures that live in the water, ICES reported a herd growth from a range of 1.2-1.6 million in the late 1960s to 1.5-2.0 million in the late 1970s.

Scientists preparing the report came from nations on both sides of the sealing issue -- the United States (high moral position against hunting harp seal pups while subsidizing a hunt in Alaska that clubs 3-year-old males), the United Kingdom, Norway, Canada, West Germany, and Holland.

As for the usefulness to man of harp seal products: no question that both the fur and oil could be synthesized. So could the products of many other income-producing activities. Whitecoat fur takes dye easily. In European stores I have seen jackets made from it as well as lesser garments including liners. The scraps do indeed decorate trinkets as charged, but scraps would otherwise be wasted altogether.

The 2 to 4 inches of fat attached to whitecoat skin renders into a quality industrial oil, used in such products as margarine and cosmetics, and also as a lubricant that holds up under greater heat than petroleum oils.

I have eaten seal meat often enough to have acquired a taste for it, as have Newfoundlanders. It has a higher protein content than grain-fed beef, and a stronger flavor. (It's a rich sea flavor, not fishy.) When the sealing ships returned to St. John's in both years that I attended the hunt, people were waiting to buy the deckloads of meat that we had gathered. None went to waste.

The Common Market took its first action to ban the products of the Canadian seal hunt in March 1982 with a vote in the EEC Parliament. This purely advisory body recommended that the commission draft a resolution to submit to the Council of Ministers. The commission agreed on a resolution in October 1982. The council (the body with authority) considered the resolution favorably in December, but appeared uncertain under which EEC treaty to base the action.

The Canadians had by then voiced their objections, including the charge that the Parliament had gathered its original material under the tutelage of only one "technical adviser" -- Brian Davies, (founder of International Fund for Animal Welfare) -- a man who has made a career of flamboyant antisealing activism for over a dozen years.

When the ICES report of last November cast doubt on the validity of charging cruelty or herd depletion, the antisealers shifted focus to "immorality," justifying the ban through an EEC provision originally drafted to curb the international flow of pornography. The council hesitated, and marked time by ordering a fresh examination of all material, to be due in February 1983 just before the start of last spring's hunt. At the last minute, still uncertain, it postponed a decision until this October.

However, the uncertainty has nearly accomplished the protesters' dreams. No sealskins of any species are moving on the international market. These include species nobody is defending, on which several Eskimo communities of northern Canada and Greenland depend for most of their income.

The principal sealskin processor, Reiber of Norway (Bergen), has laid off most of its employes. The income from fat and meat alone, while sometimes comprising up to half the total profit, still cannot underwrite the operation by itself.

If the Canadian seal hunt closes, the protest organizations will indeed have triumphed. They will have succeeded in destroying an industry for what the sealers would call sentimental reasons -- for a "morality" based on the sensibilities of urban supporters who personally do not have to kill animals to ensure their meat and livelihood.

For those whose protest was based on the sense that the seal hunt was antiecological, the irony will be particular stark. For four centuries, Europeans have had communities on the rocky coast of Newfoundland. This land is for the most part rock, and its growing season short. It is clearly inappropriate for agriculture. The people who have made their lives there are dependent on the products of the sea -- the cod and the seals.

Thus, the protesters who claim that sealing is antiecological might consider that the human inhabitants of such an area, with their needs for survival, have also become part of the ecology. If their livelihood is destroyed, so will be the portion of the ecology they represent.