It is 7.30am and I am, finally, deep in sleep on the top bunk of the cabin I have been assigned on board Greenpeace's emblematic ship - the Rainbow Warrior - when someone knocks loudly on the door.

It is the signal that everyone on board except the overnight crew has half an hour to get up, eat breakfast and - invited journalists excepted - start cleaning the decks.

It had been a rocky night at the entrance to the Strait of Magellan located almost on the tip of South America, just above Cape Horn. Lying in bed, it felt like being inside a washing machine.

Salinne, my German cabin mate, ship engineer and boat mechanic, comments that she never felt a thing, but then she's been working and sailing for Greenpeace for the past two years and has survived far worse. Clearly, I am not a seasoned sailor.

Al Jazeera cameraman Mariano Rosendi and I are on board to observe Greenpeace's newest campaign called Save the Seas at the End of the World - it refers to the southernmost waters on the tip of Chile.

Stunning scenery

The trip has taken us on a five-day journey through the strait discovered by the Portuguese navigator Ferdinand Magellan in 1520, a crucial shortcut that allowed ships to avoid sailing around the treacherous waters of Cape Horn while trying to get from the Atlantic to the Pacific, and vice versa.

The area is actually a maze of hundreds of fjords, channels and islands that form a series of basins, which means its eco-system is as delicate as the scenery is stunning.

Surrounded by spectacular visions of mountains and glaciers, its icy waters are one of the purest and home to around 36 percent of the world's marine mammals.

We spent an entire afternoon aboard a zodiac boat whale-watching around Carlos III Island, a marine mammal sanctuary in the Strait where adult and baby seals chased us.

At first, we could only see the whales from afar. But after turning off the zodiacs' motors, a very curious humpback whale came right up to the boats, swimming around and under us for 20 minutes, while the seals jumped around as well.

I've never seen anything like it. At one point, the whale raised her head to literally look into the eyes of the amazed Greenpeace activists in the boat ahead of me.

"They must somehow know that we are here on a mission to protect them," gasped Estefania Gonzalez, the spokeswoman for the new global campaign being led by Greenpeace's Chile branch.

Preserving the amazing marine wildlife in this part of the world is the reason why Greenpeace travelled to the Magellan Strait.

The Chilean salmon industry has become synonymous with the massive use of toxic chemicals and antibiotics used in overcrowded fish farms that are destroying the ocean's eco-system in areas further north in Patagonia, where the damage has been well documented.

Now, salmon farmers want to make the Magellan Straits their next main production centre.

'Nothing is wasted'

The Rainbow Warrior III is a new, state-of-the-art sail boat.

The original Rainbow Warrior was blown up in 1985 by French government agents while Greenpeace was conducting a campaign against France’s nuclear testing in Mururoa.

This new ship is as "green" as they come: it uses wind power 70 percent of the time and a fuel efficient diesel-powered electric motor the remainder; it has a desalinisation plant, a rubbish recycling system and a Mexican chef who twice a day produces gourmet organic meals (mostly, but not exclusively vegetarian) that would put many posh restaurants to shame.

Leftovers are recycled into new, imaginative meals. "Nothing is wasted," says Daniel Bravo, the chef. "It is my way of contributing to a healthy, sustainable planet."

Everyone rinses their own plates - which are then sanitised - and washes their own clothes with eco-friendly soap. Only moderate drinking is allowed after super and disorderly conduct of any kind on ship or on shore is frowned on.

Contrary to popular belief, Greenpeace activists are not a relaxed bunch of hippies trying to save the world. They are focused, well informed and well trained.

The Rainbow Warrior operates like a professional ship with a disciplined crew and strict rules for everything, including meal times, cleaning and especially safety.

The ship can accommodate 30 people, a little more than half of whom form part of the multinational crew.

They include a professional ship's captain and mates, an engineer, electrician, telecommunications expert, mechanics, a medic for the longer trips and five deck hands, some of whom have been sailing with Greenpeace for many years on three-month rotations.

Fijian deckhand Apisalom Waqanisau originally studied law, psychology and politics before joining Greenpeace, where he acquired his maritime skills.

"As a Pacific islander, we have a strong connection with the land and the sea, as most of our culture and traditions come from our connection with the land and the sea," says Api, as he is called.

"We have this innate need to protect what is ours; I saw Greenpeace as a way of actually contributing to preserving nature."

The ship can accommodate 30 people in all, including volunteers, ground staff and the occasional TV crew. Although not all the technical staff work full time for Greenpeace, all share a strong commitment to the cause of conserving nature and the environment.

"Technically this is like running any ship, but it's different because the boat has a political connotation. That means there are more risks on a Greenpeace ship than on others, although they are calculated risks," Jose Barbal, the Spanish ship captain, said.

Campaign banners

Greenpeace is famous for chasing after whaling ships, placing its boats between the whalers and their would-be catch.

But on this trip the most audacious action was to approach Chile's largest open pit coal mine, which is operating on an island that, incredibly, is also a national reserve to hang two giant banners denouncing the use of fossil fuel and calling for the protection of Chile's pristine Patagonian seas.

The whole operation lasted five hours and, on this occasion, no one was arrested.

A day earlier, another group left at dawn in a zodiac to a salmon farm that is operating in the Strait. While we watched from another zodiac, they flashed a sign with their campaign slogan.

These relatively innocuous actions in the most remote part of the world hardly seem like a threat to big business.

But when I asked if they were not being naive, Gonzalez pointed out that this was how they began many of their most successful campaigns, such as halting whale hunting in Chile and stopping Shell from drilling in the Arctic - causes that today have wide global support.

As we sail towards the Chilean Port of Punta Arenas, often referred to as the gateway to Antarctica, a pod of Chilean dolphins escort us for more than an hour, surfing the waves created by the ship.

It is a mesmerising sight - one that I hope will never disappear from these waters.