Authorities in Mexico will deploy drones on south-western beaches in Oaxaca to protect against a reported surge in turtle egg poaching of the threatened Olive Ridley turtle, which return to the country's coast each year to lay their eggs in the sand.

The sale of turtle meat and eggs has been banned in Mexico for more than two decades, but the threat of a hefty jail sentence has not been enough to deter poachers. At Ayuta Morro beach, environmental activists estimate that up to 80 percent of the beach's turtle eggs are poached a night after marines guarding the area left following security concerns in other areas of the country. Speaking in Mexico City, prosecutor at Mexico's environmental body Profepa, Guillermo Haro, told media authorities will use drones to curb poaching.

"With two drones that are the property of Profepa to surveil (beaches) Escobilla and Morro Ayuta and the result we hope for is to eradicate forever the illegal extraction of turtle eggs in these two beaches," he said.

Footage filmed earlier this month shows local residents digging at the beach in broad daylight to steal the estimated hundreds of thousands of eggs laid by turtles. Subsistent fisherman in the area can reportedly sell turtle eggs for up to 15 Mexican pesos (57p, 90¢) each. Locals living on the coast have long eaten turtle eggs, with their illegality having driven up prices. Haro added that marine intelligence will be used to stop the eggs reaching the market.

"This will be accompanied by intelligence work by marines in the ocean and land to detect what I said previously (turtle egg poaching). Not just the extraction but the commercialisation, distribution, sale and in markets where they're sold," he said.

Humans are the biggest threat to Mexico's turtles, but baby turtles and eggs are also hunted by birds, dogs, crabs and sharks. It is estimated that on average, out of 10,000 that hatch, just 0.02 to 0.2 percent of turtles reach adulthood, environmental experts say.