Every winter, somewhere along the coast of Baja California, a pod of pregnant grey whales cruises past the US-Mexican border, swimming south, well offshore from the grim, polluted cities of Tijuana and El Rosario and the untreated sewage that pours into the ocean. The whales continue their extraordinary 6,000-mile migration from the frozen Arctic south, down the Baja peninsula. And it is there that they face their greatest threat - an economic boom comparable to the great Californian land rush of 100 years ago.
Geographically, Baja California is the longest and narrowest peninsula on earth, and this remote area of Mexico offers a precious refuge for the grey whale. Although among the first whales to be removed from the endangered species list, there are only 18,000 greys left in the wild and their future is by no means certain. The filter-feeding whales, measuring up to 45 feet (15 metres) long and weighing some 30 tons, spend the summer feeding in the plankton-rich waters of the Bering and Chuckchi Seas and winter in the warm lagoons off Baja California, where their calves are born.
But the race is on to develop Baja California. It is hoped that industry and holiday enclaves will help end the grinding poverty that causes so many Mexicans to flee for El Norte. But there are well-grounded fears that development will also diminish and ultimately destroy a delicate ecosystem of desert and coastal ecosystem and with it the breeding and feeding grounds of turtles, dolphins and grey whales.
Once past the US-Mexican border, the whales head 600 miles further south until they reach Laguna San Ignacio. This is one of Mexico's most remote regions, a vast landscape of water and desert where migratory birds feed, mangroves thrive and the once endangered whales migrate to breed and bear their young. Laguna San Ignacio first became a successful rallying point for environmental groups from both sides of the border in the mid-1990s when salt evaporation ponds were proposed for the shores of the lagoon by Mitsubishi Corporation.
The salt works would have irreversibly altered the ecology of the lagoon as has happened else on the coast of Baja in at least two other similar locations. They were blocked, and in 2003, the lagoon and another grey whale breeding site, Laguna Ojo de Liebre, were designated United Nations World Heritage sites. Then the property speculators started to move in, triggering another battle to save the lagoon.
However, a highly unusual agreement has just been negotiated between environmental groups and a local cooperative, which means that this vital stretch of water, the last undisturbed grey whale nursery along the vast Pacific coastline, is to be spared from industrial development and land speculation. For the first time, local residents have called a halt to land speculation along the sparsely settled and biologically wealthy stretch of the Baja California peninsula.
Protected from the pounding surf of the Pacific by sandbars, Laguna San Ignacio, surrounded by salt flats, mesas and desert, has been a sanctuary for grey whales for centuries. The pod of pregnant whales enters the lagoon through a narrow inlet and move onwards for almost ten miles to a warm, shallow, isolated sector of the Middle Lagoon to give birth.
The newborn whales are dark and pinkish -and at birth are already 15 feet long and weigh almost a ton. Within moments of birth, the calf swims to the surface to take its first breath, its flippers and flukes still flaccid and crumpled from being folded for 12 months inside the mother whale. Once the young are born, the whales mate again, their vast barnacle-encrusted fins slapping the shallow water as they frolic, breaching and flopping their giant bodies. "It is one of the great wildlife experiences anywhere in the northern hemisphere to go to this lagoon and interact with the whales at close range," said Joel Reynolds, director of the mammal protection program of the Natural Resources Defense Council.
Local fishermen, who work as eco-tourist guides while the whales over-winter, bring tourists to the middle of the lagoon to watch the so-called friendly whales play around the boats. The whales are so approachable that visitors can pet and scratch their blubbery, sensitive tongues - although this is severely frowned upon by conservation authorities.
But while the lagooon may be safe, environmentalists worry that a massive development programme at Loreto, just four hours away, will pose yet more danger to the fragile ecosystem.
Mostly scrub desert, Baja stretches for more than 800 miles. It is no more than 60 miles across at any given point. The Pacific runs from Tijuana down to the resort town of Cabo San Lucas. And to the east, between the peninsula and the mainland of Mexico, flows the Gulf of California, or Sea of Cortés.
Up and down this finger of land, speculators from the US and Canada are busy offering huge amounts of money to subsistence farmers and fishermen to buy up vast tracts for development of the most unspoilt and rich coastal habitats in the world.
"A speculator comes in and offers $25,000 or more for a plot of land that was worthless a few years ago," said Dr William Megill an expert on the region's environment from the University of Bath. "All too often the social consequences are disastrous, with money being drunk away and the land ownership changing."
Desert mesas and endless beaches best known to a band of adventurous surfers and ecologists are now in the process of being sold off to be turned into developments of villas and condominiums for North American holidaymakers. The development underway outside the once small town of Loreto is expected to rival Cancun with all its brash garishness and will house some 35,000 visitors and the obligatory cluster of golf courses.
"When villas are on sale for half a million dollars, it is easy to bring in water desalination plants and suddenly the entire desert ecosystem is threatened by sewage and waste runoff," said Dr Megill.
The move to protect the whale nursery at Laguna San Ignacio has brought some rare cheer to environmentalists like Dr Megill who receives funding from the charity Earthwatch to study grey whales both in Mexico during winter and off British Columbia in the late summer.
Under the deal, the cooperative, known as the Ejido Luis Echeverría, has agreed in perpetuity to protect 120,000 acres around the lagoon from development, in return for a $675,000 trust fund put together by several groups, among them Wildcoast and the Natural Resources Defense Council.
Earnings from the trust will go to the cooperative to be invested in sustainable development projects to create long term jobs and give its 43 members a stake in protecting the habitat of the whales. "This is a long-term project, a project for perpetuity," said the president of the cooperative, Raúl López. "We have to be an example for the other cooperatives."
The agreement involves the largest piece of property to be placed in a private land trust in Mexico. It is one of very few such arrangements involving an ejido, a form of communal landholding created under Mexico's 1917 Constitution to distribute property among landless Mexicans.
"Everyone in Baja California Sur is thinking about selling their land, but we're going to show that you don't necessarily have to sell," said Raúl López Góngora, whose members subsist through fishing and ecotourism. "Maybe we can set a precedent for conservation in the region."
In exchange for blocking development, the Ejido Luis Echeverría will in perpetuity receive $25,000 a year from a trust fund. ProNatura, Mexico's oldest and largest conservation group, will ensure the money is spent only on environmentally sustainable development projects.
Nearly to 80 per cent of the Baja California peninsula is in the hands of ejidos, and conserving coastal lands depends on securing their cooperation. For decades, ejido property could be neither bought nor sold. But changes in the 1990s allowed for the privatisation and sale of the communal property. Land-rich but cash-poor, growing numbers of ejido members are opting to sell their parcels, and the buyers are often developers and land speculators.
A coalition called the Laguna San Ignacio Conservation Alliance has now been established amid hopes that five other ejidos could be persuaded to sign similar agreements, and that eventually one million acres would be protected in private trusts.
"The idea is that the community itself decides, 'this is what we want for the future, and this is how we can best use our resources'," said Miguel Àngel Vargas, who runs ProNatura. "I don't think we could save these areas without such agreements. What we're doing is taking preventive measures."