The scenery is almost postcard perfect: a tiny beach nestled in a cove and surrounded by a lively mangrove forest ecosystem.
But local fisherman Bulfrano Castillo is worried major hotels are rising up around the beach, and the owners are telling local people to scram.
"They can't just kick us out," Castillo says, standing beside his boat. "We pay our taxes and have everything in order."
Hotel construction in this cove began two years ago and Castillo says the new resorts are damaging the mangrove ecosystem and hurting fish populations.
"Everything used to be really green, there were deer and iguanas but now a lot of the trees and animals are gone," he says.  "At night the construction site has lights, so the fish don't come near and the workers throw things into the sea."
Castillo and a dozen other families run a small co-operative restaurant on the beach, serving fresh fish from the ocean mostly to local people who come on the weekends for sun, sand and natural beauty.
The co-operative has been fighting to stay on the land, which Castillo says belongs to the federal government and is controlled by the tourism promotion department, Fonatur.
The showdown on this small beach represents larger tensions between development and environmental protection in Oaxaca.
The city of Huatulco and surrounding areas are in the midst of a tourism boom, fuelled largely by Canadian retirees who want to buy-up a little piece of heaven. The region isn't experiencing the same drug-related violence as Acapulco and other Mexican tourist hot spots, and it is still relatively underdeveloped compared with other areas.
"There are two extremes destroying the mangroves," says Eugenio de Jesus Villanueva Franck, a biologist who co-ordinates the national park in Huatulco. "Poor communities destroy them through deforestation, because they have no other way to survive. But private developments are the biggest threat."
Mangroves are a specific kind of tropical eco-system: marshy zones located where the water meets the land, populated by various birds, unique fish, and reptiles including iguanas and crocodiles.
They help cleanse the planet, taking greenhouse gases like carbon dioxide out of the atmosphere, while acting as a buffer against soil erosion.
In Mexico's coastal areas, mangrove habitat declined from 1,041,267 hectares in 1976 to 683,881 hectares in 2007, Greenpeace Mexico warned in a 2009 report.
If destruction continues at its current rate, the country will lose 40 to 50 per cent of its existing mangroves by 2025.
"Once investors develop hotels, there is no reversing the process. With rural communities, there is a way back, but it may take some time," Franck says during an interview at his office.
Castillo and his friends at the co-operative restaurant are not part of the problem, as they fish in small boats and do not cut down the trees.
But other rural communities, especially newer arrivals to the coast, have caused significant damage.
The Mexican government built connector roads from mountainous inland regions to the coast in the 1960s, leading peasants to migrate from the highlands into the mangroves.  At first, they would just come for short periods to fish and hunt turtles. But later, they began to settle permanently.
"Cattle farming, unplanned population growth and deforestation brought a series of negative impacts," says Jorge Rocha Rodriguez, an environmentalist in Huatulco, working to protect the mangroves.
In addition to new populations in the region, the 1960s saw the beginning of privatisation, where tracts of land, which had belonged to entire communities, were parcelled off to individuals.
Speculators began buying large tracts of coastal property, after peasants sold it for low prices, Rodriguez says.
Privatisation wasn't just about the land itself the mindset of people in the area started to change when the mangroves became a commodity.
"Communities who were not selling their land became integrated in the new market, Rodriguez says. "To respond to market needs, they started cutting the mangroves to create more farm land and they began using a lot of pesticides, especially for growing papayas."
Animals also faced over-exploitation, with the sea turtle population taking a major hit. "People exported the meat and eggs," says Rodriguez.
Facing international outcry over the decline in turtles, Mexico's government created the National Commission for Natural Protected Areas in 1994, although Franck, the biologist, says rules for protecting areas like the mangroves were not enforced until 2005.
Battle over conservation
Today, there is a battle over conservation between various agencies within the Mexican government. Fonatur is pushing for increased foreign investment - and nothing sells like ocean-front property, a prime area for mangroves. The national parks department and other bodies are fighting back, trying to preserve protected areas from hotel and condo development.
In coastal communities still populated by peasants, environmentalists like Rodriguez have been running education programmes to teach people about the value of the mangroves, and they seem to be having an effect.
"The land is not for sale in our community, we are well organised," says Juan Elorza Zarate, a farmer from Barra de la Cruz, a prime surfing destination with rich mangroves. Zarate moved to the lowlands in 1964, and he says people in the town are more aware about the need to preserve the eco-system than they used to be.
"We are peasants and we work the land I have no worries about the mangroves as long as the community keeps taking care," he says, in what may be an overly optimistic assessment.
Still, it does seem true that deforestation is remitting in some communities as awareness rises. But the scale of long-term, irrevocable destruction from major tourism developments is increasing.
"The new golf course at Tangolunda used to be a mangrove," says Franck.
And, he says, it is almost impossible to turn manicured grass, owned by a private company, back into a thriving eco-system.