QUESTION: Do you have information on discounts that ships may provide for filling an empty cabin on short notice?

ANSWER: Cruise lines do indeed offer discounts for unsold spaces on ships, and these are called last-minute fares.However, in recent years last minute has come to mean 30 to 60 days ahead of time, not a few days.

Such discounts average 30 to 40 percent, according to agents specializing in cruises, and can go as high as 50 or 60 percent, usually on more expensive fares .

You may find a discount with only a few days' notice, but the saving will not likely be any less.

Also, it will be harder to find a package that includes air fare at such notice, travel agents say.

In some cases, the cruise lines advertise last-minute discounts to the public, and in others the discounts are made available through companies that specialize in discount cruise rates.

It is useful to call such agencies in any case, especially if you have a particular route and time in mind, as the agencies are up to date on where spaces remain. Among the companies:

The Cruise Line, 260 Northeast 17th Terrace, Suite 201, Miami, Fla. 33132; (800) 327-3021 or (800) 777-0707. Callers can speak with an agent or listen to a 24-hour line with a 60- to-90-second recording giving the best of last-minute deals.

Among the saving are a seven-day Caribbean cruise, normally $1,995, for $995 with air fare; 10-day Caribbean cruises for $1,295, worth up to $2,320; and two-for-one discounts on cruises to South America and the South Pacific.

Vacations to Go, 2411 Fountain View Drive , Houston, Tex. 77057; (800) 338-4962. Thirty to 90 days in advance, callers can listen to a recording listing 10 discounted cruises or can speak to an agent.

Spur of the Moment Cruises, 10780 Jefferson Boulevard, Culver City, Calif. 90230; (800) 343-1991 or (213) 839-2418. This company offers a seven-day Caribbean cruise with air from major cities, regularly $1,395, for $699. It also has a Mexico cruise for $539, not including air fare; the cruise is regularly $1,395, the company says. By calling (213) 838-9329, you can get a six-minute recording of newly offered discount cruises.

World Wide Cruises, 80955 West McNab Road, Fort Lauderdale, Fla. 33321; (800) 882-9000 or (305) 720-9000. This company says it regularly offers cabins that are normally $1,400 to $1,500 for $899 to $999. Until Feb. 10, it is offering inside cabin space normally $1,600 or $1,700 on a cruise out of Florida to Nassau, St. Martin, St. John and St. Thomas for $919, including air fare from Newark.

Cruise Reservations, 8975 Northeast Sixth Avenue, Miami, Fla. 33138; (800) 892-9929. The discounts average 20 to 25 percent, the company says.

A service called the Cruise Shoppers Hotline offers information on discounted fares at (900) 740-3400, for $2 a minute.

The service is an offshoot of the Cruise Director, a company in Denver that handles reservations for cruises.

The information is organized by destination, so callers seeking information on Caribbean cruises, for example, obtain that segment, which lasts about 10 minutes, by pressing a number on a push-button phone.

QUESTION: Can you give me information on visiting Manitoba to observe polar bears?

ANSWER: After spending the summer living on the tundra, polar bears gather in October on the southern shore of Hudson Bay, near Chuchill, Manitoba, to wait for the bay to freeze.

Once it does, usually in the third week of November, the bears will live on the ice, hunting seals for food, until it melts again in early summer. In October, visitors go there too, to see the bears.

Visitors often travel in Tundra Buggies, vehicles with huge balloon tires that allow passengers to get near the bears yet be high enough above them to keep humans safe and bears undisturbed. Temperatures range from 10 degrees to 30 or 40, and warn clothing is recommended.

Joseph Van Os Photo Safaris will offering 11 tours from early October through Nov. 6, 1991.

The tours will be of two types. The first, six days, for $1,855 a person, starts with a night in Winnipeg followed by three nights in Churchill. The days are spent on the tundra watching bears and other wildlife. The second, eight days, $2,695, includes three nights in Churchill and three nights in a mobile bunkhouse on the tundra at Gordon Point.

The company says the bunkhouse is designed to keep visitors protected from contact with the bears, but movement outside the house is strictly limited. The costs include lodging, meals and flight between Winnipeg and Churchill. Joseph Van Os Photo Safaris, Post Office Box 655, Vashon Island, Wash. 98070; (800) 368-0077 or (206) 463-5383).

Big Five Expeditions runs an eight-day tour for $2,235 out of Winnipeg led by a naturalist photographer. Included are three days of Tundra Buggy exploration and a tour in low-flying four-seat planes. Departures are Oct. 9 and 30.

Tundra Buggy Tours, which operates the vehicles and the bunkhouse, offers tours out of Churchill from 8 a.m. to 5 p.m. for about $109, including lunch and refreshments.

From Nov. 7 to Nov. 22 or 23, the bunkhouse is moved to Cape Churchill, about 25 miles east, where, the company says, larger bears and mothers and cubs are more numerous. Guests can stay there Nov. 7 to 14 for $2,277 or Nov. 14 to 23 for $2,860. Tundra Buggy Tours (Post Office Box 662, Churchill, Manitoba R0B 0E0, Canada; 204-675-2121 June until late November and (800) 544-5049 the rest of the year.

QUESTION: Are there directories of cottages for rent in England?

ANSWER: A booklet called "Holiday Homes 1991" should be available, at no charge, starting this week, according to the British Tourist Authority.

The publication lists cottages as well as apartments and motor homes available throughout Britain. To get a copy, contact the British Tourist Authority, 40 West 57th Street, New York, N.Y. 10150; (212) 581-4700. NYT-01-21-91 1120EST