By Peter Greste in Mexico City

Hundreds of Mexican street clowns are holding a convention aimed at giving their art the respect they say it deserves.

It is Mexico's 8th Annual Clowns' Convention, and the clowns have gathered in one of the capital's main parks to pick up new skills, swap ideas and showcase their talents.

The street performers are a hugely important part of Mexican culture and economic life.

Thousands of them occupy traffic inter-sections across the country and leap out from behind traffic lights to entertain drivers, earning a few pesos as they clown around.

They say theirs is the toughest form of clowning in the business and the two-day convention in Chapultapec Park is aimed at maintaining high standards of clowning.

Shocking orange hair

Somehow it didn't seem quite right - clowns watching other clowns clown around.

They are after all the ones supposed to be doing the performing for, well, normal people.

But this was a very serious event - the national championships if you like for Mexico's street entertainers.

In all 800 came from across the country to cavort in their bizarre and surreal make-up around Chapultepec Park, which dominates the heart of the capital.

Judges with greasepaint, big red noses and shocking orange hair assess the contestants who are made up with, well, greasepaint, big red noses and wild blue hair.

Among the categories - the best crazy face, the best vagabond, best knotted balloon and the best juggler.

Raising smiles

And the aim of it all? The organiser, who goes by the name of Chispin or Sparky , said he wanted to raise the image of what he called popular clowning.

"The popular clowns are considered the lowest form of entertainers," he told me, "but actually the street work is the hardest of all because we're trying to earn a living from grumpy people who are locked in their cars and stuck in traffic."

Chispin estimates that there are some 2,000 street clowns who work the intersections across Mexico trying to raise a smile from the commuters in exchange for a few pesos.

It is not a unique tradition but it is one with deep roots here.

The first clowns came from Spain 200 years ago and their numbers are increasing as unemployed turn to the streets to survive.

Another clown called Chispinita Vitmitia says it's a tough way to make a living.

"But when I get a laugh out of the office workers, it's all worthwhile. I couldn't go back to normal work."