The colossal creatures are surprisingly friendly, given they were twice brought close to extinction from hunting in the past two centuries. Newborn calves approach the small tourist boats and allow their barnacled, rubbery skin to be scratched.

But the idyll is a precarious one. Resentment from the community of San Ignacio village, a two hour's drive away, and attempts by the government to tax whale-watching as a luxury activity could jeopardize the future of resorts like Kuyima.

Locals resent the moderate success of the ecologically conscious Kuyima, which receives around 1,200 visitors to the lagoon every year, most paying $150 a night - a small fortune in the impoverished region that depends on fishing revenues.

A controversial government project two years ago to build a salt plant in the lagoon further divided the area.

While locals saw the plant as a potential source of jobs, resorts like Kuyima joined a massive Mexican and international protest warning of risks to the gray whales that migrate south to breed from January to April in the warm-water bay.

The project was put on hold, compounding the unpopularity of the ecoresorts on the lagoon among locals.

And now the federal government is threatening to slap a series of crippling taxes on whale boats to raise revenues, which could kill the eco-tourism industry in its infancy.

"We have received a lot of blows," said Raul Lopez, a guide and operative coordinator at Kuyima and president of the local association of tourism service providers.

"People want to say we are monopolizing the regional economy. We're just a group that is vocal and dedicated to the environment and don't let ourselves be manipulated," he added.

FRIENDLY WHALES

Up to 17,000 gray whales are believed to migrate more than 5,000 miles (8,333 km) south from the Bering Straits every year, many stopping to breed in Mexico's warm-water lagoons, like San Ignacio, a designated World Heritage Site.

Until the 1970s, local fishermen kept their distance from the whales, fearing they might attack given man's historical brutality toward them. But one day a curious whale approached Francisco Mayoral out fishing and refused to be scared away.

Seeing how friendly the creatures were, Mayoral began the first whale watching tours in the lagoon shortly thereafter.

Lopez, a fisherman from northern Sinaloa state, and several others followed suit, forming Kuyima in 1993 as a community project and then registering it formally as a business.

The resort, which employs 50 mainly local people, according to Lopez, was inspired by hopes of pioneering environmentally friendly tourism in Mexico.

"When we started we targeted the national tourist market but soon realized it was one of the most expensive destinations in Mexico." Lopez said. From Mexico City, airfares to Guerrero Negro, two hours away by bus, are $700 compared with around $350 to Cancun. "Increasingly our natural market is the U.S."

With its arid deserts, dense jungle, rocky mountains and teeming coastlines, opportunities for eco-tourism in Mexico are vast but expensive since state and federal governments tend to invest in big glitzy resorts like Acapulco and Cancun over infrastructure for off-the-beaten-track resorts.

"There's a lack of understanding" of eco-tourism, said Jorge Belmonte, subdirector of alternative tourism in the tourism ministry. "The perception is that it's very elitist and that logically harms the development of eco-tourism at a national level." But that's changing, he said.

Mexico's tourism ministry this year signed a deal with various government ministries and agencies to invest $250 million in eco-tourism, compared to just $50 million last year.

The number of operators offering ecological tourism in Mexico has risen 500 percent in the last five years, with some 400 firms claiming to provide environmentally aware tourism.

MARGARITAS AND LOBSTER

Kuyima relies on publicity by word of mouth and sees its brand of tourism as morally superior to that offered by package resorts pretending to be eco-friendly, according to Lopez.

"We don't want to fall into marketing which is outside our concept of what eco-tourism is. Big chains put on the name 'eco' and try to pass what they do off as eco-tourism ."

Kuyima has 10 simply furnished, rustic cabanas lining the shore - on stilts for minimal environmental damage - and a camping area for budget guests for whom tents are provided.

Visitors sip margaritas watching the setting sun splash vibrant reds and oranges across the sky above the lagoon, which stretches unspoiled to the horizon in all directions. Guests dine on lobster and fresh fish in a wooden dining room where talks are given about the whales and natural life in the bay.

San Ignacio, located in North America's largest wildlife sanctuary, the Vizcaino Biosphere reserve, receives around 3,000 visitors annually, of which nearly half stay in Kuyima, Lopez said. About 90 miles (140 km) up the coast, the larger Scammon's Lagoon gets up to 10,000 visitors a year.

Local hostilities to the resorts on the lagoon are immediately evident in the dry, dusty town of San Ignacio.

"Oh you don't want to go to Kuyima. It's the most expensive of the lot," said hotel and restaurant owner Ricardo Ramos.

Taxis, all unionized, charge high prices to take visitors on the two-hour journey on the dirt road out to the lagoon. The fact that Kuyima has an airstrip and its wealthy guests bypass San Ignacio town altogether further irks locals.

Kuyima owners "aren't all from here, some are from other states. They should give more jobs to people from here," said taxi driver Reyes Duarte Sanchez, who is himself from Guerrero state. "They share the profits among themselves."

CRIPPLING TAX HIKE ON HOLD

Kuyima and other whale-watching outfits narrowly escaped having to pay a raft of hefty new taxes this year.

The big business-friendly government of President Vicente Fox imposed an annual levy of 1,020 pesos ($110) per seat for each 10-man boat plus an added charge per visitor and a tax for using shorelines, which all are government-owned.

With Kuyima's 12 boats, it would have paid around $13,200 a year in levies just on seats. However, the resorts appealed the ruling and have been granted a stay on the new charges until the issue is resolved by Congress.

"The government doesn't bring us any benefits," said Lopez, noting there were no running water, electricity, telephone lines or sewage systems on the lagoon.

The tourism ministry's Belmonte said delaying the taxes wasn't the solution. The resorts have to challenge them in court and make a formal protest, he said.