Icelandic whalers have spent much of July ripping back the skin of 65-foot long endangered fin whales in preparation to butcher their meat.

Earlier this month, the commercial whaling company, Hvalur hf, may have also captured and skinned an endangered blue whale -- the largest creature ever known to live on Earth -- according to photographs from the ocean conservation and vigilante group Sea Shepherd.

Most every nation has prohibited killing whales, creatures whose populations were decimated by ruthless whaling practices in the 1800s. International treaties also prohibit the antiquated practice, yet a few nations -- Iceland, Japan, and Norway -- have found legal rationals for hunting whales.

"People assume whaling is an artifact of the past -- but it’s not," Harry Scheiber, a marine law expert and former director of the University of California at Berkeley's Law of the Sea Institute, said in an interview.

Iceland's recent killing of whales, however, which Sea Shepherd Captain Paul Watson said has numbered 27 fin whales since June 22, has tenuous legal ground -- but the Icelandic justification for hunting whales has still allowed the nation to hunt the mammals with near impunity.

The International Whaling Commission, of which Iceland is member, prohibited killing whales in 1986. Yet, in late 2002 Iceland filed a "reservation" to the treaty, in which they said they would no longer agree to the moratorium on whaling. And legally, Iceland can do this. The whaling commission doesn't create binding law. It's more of a formal agreement of faith.

"See, none of this is compulsory," said Scheiber, noting that any nation can opt out of a provision.

"That’s a loophole."

"If you don’t comply there really aren’t many consequences," Brett Sommermeyer, legal director of Sea Shepherd Legal, an environmental law firm and sister organization to Sea Shepard, said in an interview. "There's public shaming, but there are not any economic consequences."

"It's not the same as national legislation with meaningful penalties," added Catherine Pruett, executive director of Sea Shepard Legal.

So, although many of the world's nations might find the activity repulsive, Iceland has found a way to commercially whale and sell the meat to Japan, some touristy Icelandic establishments, and even a microbrewery that infuses fin whale testicles into its beer.

The International Whaling Commission allows each nation to remain sovereign over its own whaling laws, said Scheiber. And in Iceland, whaling is a proud tradition.

"Icelanders consider themselves a very humane society and are offended that they’re doing something bad by whaling," said Scheiber. "There is a strong tradition of whaling -- it’s handed down from generation to generation."

But Iceland's loophole has some big problems

Not everyone believes Iceland's whaling loophole is legitimate.

"It’s illegal," said Sea Shepherd's captain Watson. "U.S. law says they should be punished for what they’re doing."

Watson is referring to the Magnuson‐Stevens Fishery Conservation and Management Reauthorization Act of 2006, which states that foreign nations should be punished for plundering endangered species and engaging in illegal fishing.

Both fin and blue whales are considered endangered under the U.S. Endangered Species Act, meaning "a species is in danger of extinction throughout all or a significant portion of its range."

Of course, the U.S. isn't ever going to raise arms over the killing of threatened whales. Instead, the marine law cites a possible denial of U.S. port access for fishing vessels, and "potential import restrictions on fish."

But Sea Shepherd might consider more direct intervention, said Watson. He gave no specifics, but cited the way the vigilante group spent years chasing Japanese whalers, to apply pressure onto the Japanese government and document exactly how many whales are being killed.

Without efforts like Sea Shepherd's, it's nearly impossible to know exactly what the whaling company Hvalur hf, and its millionaire owner, Kristján Loftsson, are doing at sea.

"This guy can do whatever he wants -- he’s one of the richest men in Iceland," said Watson.

According to the permits issued by the Icelandic government, Hvalur hf can kill fin whales for commercial purposes. But not blue whales, which makes the recent blue whale killing, if proven, a clear violation of Icelandic law.

But killing fin whales may also be illegal

When Iceland filed its "reservation" to the whale killing moratorium in 2002, it specifically stated that commercial whaling would "under no circumstances" be allowed "without a sound scientific basis" and population management plans.

This makes hunting any endangered, struggling whale species problematic, at best.

"It seems clear that Iceland is in violation of its own reservation, as there can never be a 'sound scientific basis' to commercially hunt endangered whales," said Sommermeyer, the legal director.

What's more, Sommermeyer notes that not every nation has accepted Iceland's 2002 reservation.

"Thus, from the perspective of many nations, Icelandic whaling is illegal because it is undertaken on the basis of an invalid reservation," said Sommermeyer.

For now, Iceland may be holding onto its whaling heritage, hinged to a shaky loophole. But they have little global support for killing endangered, intelligent, and often friendly creatures.

"It’s condemned by most of the world," said Sommermeyer.

"What’s disturbing, of course, is the taking of whales that are clearly an endangered species," saidScheiber.

"The whales have suffered enough," he added.