PARIS (AFP) - The International Whaling Commission starts a crucial five-day meeting Monday in Agadir, Morocco that could break a 24-year deadlock and usher in a sea change in the global whaling regime.

• Whale hunting could halt Iceland's EU talks

Here is some essential knowledge about how the IWC works, which whales are hunted, and the countries that hunt them.

INTERNATIONAL WHALING COMMISSION (IWC)

Set up in 1946, the IWC's 88 members are roughly divided between those that back whaling nations Japan, Iceland and Norway, and countries whose main priority is the conservation.

Pro-whaling nations include most of Asia, a number of Caribbean and African states, and Russia. Countries hostile to whaling led by Australia include the European Union (except Denmark), most English-speaking nations (including South Africa, Kenya and India), and all of South America.

THE MORATORIUM

In 1982 the IWC voted to implement a moratorium -- what it called a "pause" -- in the commercial hunting of whales.

The ban went into effect in 1986. Three countries -- Japan, Norway and Iceland -- have used loopholes in its wording to unilaterally resume hunting of several whale species.

LEGAL FRAMEWORK FOR WHALING

Any IWC member can object to the moratorium, declaring itself exempt. Invoking this provision, Iceland killed 38 whales in the 2008-2009 season, and Norway killed 539.

A country can also set its own "scientific permits" for whaling, ostensibly to further research on conservation. Under this rule, Japan harvested 1,004 whales in 2008-2009.

The IWC grants permits to indigenous peoples to carry out traditional and subsistence whaling. Native peoples in Russia, Alaska and St. Vincent and the Grenadines all have quotas.

"BY-CATCH" WHALING

Every year whales get caught in fishing nets and die, especially minke in coastal waters off of Japan and South Korea. Since 1996 both countries have reported these ostensibly accidental catches which, in the case of Japan, have steadily increased.

Over the 12 year up through 2008, each country has acknowledged more than 1000 whales lost to by-catch. Products from these whales are sold openly in both countries, and DNA analysis suggests that the actual number killed may be twice as high.

WHALE SPECIES HUNTED

The IWC regulates hunting of a dozen large whale species, including filter feeders and a few deep-diving "toothed" whales.

The global stocks for many, and how far they have declined, are simply not known, making it nearly impossible to set scientifically-based catch quotas.

In recent years, the three whaling countries have mainly hunted six species in different waters around the world: Antarctic minke whales, up to 10 meters (32 feet); Northern Hemisphere minke whales, up to 9 meters (30 feet); Fin whales, up to 24 meters (78 feet), 70 tonnes; Bryde's whale, up to 14 meters (46 feet); Sei whales, up to 16 meters (53 feet); Sperm whales, up to 15 meters (49 feet).

ADDITIONAL THREAT TO WHALES

Commercial hunting and by-catch are not the only direct threat to whales. A lesser number are hit by ships, especially where migratory paths overlap with busy shipping lanes.

Other threats, more difficult to quantify, include: chemical pollution; noise pollution, especially from high-decibel military exercises and oil exploration; environmental degradation; climate change; over-exploitation of prey.

More recently, scientists have argued that whale watching may also disturb the feeding, mating and migratory behaviour of some whales.

WHALE SANCTUARIES

There are currently two major whale sanctuaries. One covering most of the Indian Ocean was created in 1979 following an initiative by The Seychelles, and is a breeding ground for many southern hemisphere cetaceans.

The Southern Ocean sanctuary, surrounding the continent of Antarctica, was proposed by France and set up in 1994. Its waters, teeming with marine life, serve as a feeding ground for more than a dozen whales species.

Japan has harvested nearly 10,000 whales there in the name of scientific research since 1982. A proposal on the table in Agadir would reopen the area to commercial hunting.

(Sources: IWF, WWF, Jean-Benoit Charrassin, Vincent Ridoux, Museum of Natural History in Paris)