The Oaxaca coast: Great-tailed grackles, magnetic sand and fat-fighting trees

It might sound spoilt but we were beached out. Lara has absorbed more sunrays than Brighton beach did in a year; I’d ingested enough saltwater than the Gray Whales cruising off the coast.

It was time to get away from the bracelet-braiding hippies and the bongos of Mazunte, the nudists and the rudists of Zipolite and see some birds of an altogether different plumage.

And where better a place to spot them than Ventanilla lagoon, a murky tract of water and dense mangrove swamps tucked away off a beach just a short Camionera ride away.

Half an hour later we found ourselves gingerly crossing Ventinilla beach in flip flops, the sand too hot for bare feet.

The dark patches streaking the sand denoted the high iron content of the sand, something proven to us by our young guide who whipped out a magnet which, quite extraordinarily, instantly sprouted a Ken Dodd-style hairdo when passed near the sand.

Perhaps the unusual geology also helped explain the wreck of an old aeroplane, lying in the surf up ahead like a prop from Lost.

According to local hearsay it was running drug smugglers, who then cut and run (excuse the pun) - the locals must have had a big party.

More unusual sights awaited us as we clumsily clambered on board a small rowing boat and headed out into the lagoon.

It was like entering the Lost World, a multitude of strange birds call ascending our ears, calling and cackling, whooping and whistling.

Our eagle-eyed guide, armed with a well-honed knowledge of the lagoon and the creatures that dwelt within it was soon picking out a veritable menagerie from the shadows that this short-sighted Englishman would have glided right by.

The birds came in all shapes and sizes - from tall, elegant fish-eating egrets to tiny, flitting seed-eaters - and were painted in the most fantastical palate, a range of surrealist colours which might have come from the mind of Syd Barrett.

They had suitably bizarre names too, to match their strange appearance, reading like a list of characters from a Roald Dahl book: boat-billed heron; yellow-rumped cacique; pelagic cormorant; tropical kingbird; green kingfisher; pileated woodpecker; great-tailed grackle.
But no Norwegian blue.

The waters beneath held no less impressive an array of creatures.

It being the tropical south we encountered crocodiles, passive yet disturbing in only the way a crocodile can be, their eyes and the scales of their backs just breaking the water, lying still, all brooding malice.

Turtles poked long, thin necks up out of the water into the brilliant, seemingly unconcerned by the deadly killing machines eyeing them from the banks.

Back in Mazunte’s turtle centre we had seen these creatures up close, staring out at us from behind plastic windows, their expressions strangely human. When a staff member told us that turtles could cry, I believed him.

Mexico boats seven of the world’s eight species of these incredible creatures yet, strangely enough, it wasn’t until 1990 that the government banned their hunting.

Old, faded posters, dating from this time, are displayed in the centre, seeking to puncture the popular myth that turtle eggs were an aphrodisiac.

Two feature different people which appeal to Mexican machismo: one a scantily-dressed woman posing below the caption ‘My man doesn’t need turtle eggs’; the other featuring a lucha libre (Mexican wrestling) legend, Santo ' vs. those who eat turtle eggs’.

Back in Ventanilla, we edged further in, out of the green waters of the lagoon into the dark recesses of the mangrove swamps.

The trees closed in, the water grew shallower. Here dwelt the red mangroves, bizarrely-shaped arboreal wonders, upside-down organisms reflected the right way up in the water.

These trees are crucial to the local environment, serving as natural barriers against the encroaching sea, filtering out pollution and in the process turning the water a dark, brackish colour, their odour eggy and pungent.

Dead bodies of their larger brethren scattered the narrow waterways, victims of 1998’s Hurricane Paulina, which laid waste top large tracts of the Oaxaca coast.

Green iguanas scuttled amongst the trees, crazy patterns down their backs descending into a long, thin whip of a tail. Prehistoric-looking creatures in an primeval-looking habitat.

The forebears of this lagoon’s inhabitants dwelt on this planet long before Adam started eyeing up Eve, long before the happy couple’s descendents discovered the potential of burning carbon, and certainly long before billions of these buggers swarmed all over the planet, heating up their home and threatening to turn it into an uninhabitable place once more.

Back to the ancient gloopy stuff out of which they once crawled? Certainly tearing up the mangroves won’t help avert this.

These extraordinary habitats are the most threatened in the world, with only 1% of the planet’s mangroves protected.

In Mexico they are destroyed to make way for shrimp farms and new hotels, their durable wood harvested for western markets.

This is tragic: the world needs mangroves. These vital ecosystems support a huge diversity of wildlife, preserving endangered species, providing local communities with the essentials of life, protecting coastlines from erosion by the sea and even absorbing the impact of tsunamis.

And Mexico needs them too. Even if you are the most landlocked citizen, even if you don’t care for the environment think of the fatties, for here the mangrove’s bark has been used to treat diabetes.

Given the obesity crisis facing the country - now the second ‘fattest’ in the world and the accompanying diabetes crisis (this disease is now the number one cause of death amongst Mexicans, threatening to financially cripple the country‘s health care system) it looks as if these trees might be required to strip a little bit more.

That’s unless Pepsi’s new computer game, designed to help kids live healthy lifestyles can reduce waistlines instead.

Obesity-fighting computer games? Perhaps it was time to head back to the beach.

You can help preserve mangrove forests by buying environmentally-sustainable products. When buying shrimps or wood products check the label to ensure that the product you consume is not contributing to the destruction of mangroves. Visit http://www.mangroveactionproject.org/ for more information