McQueen in Venice Photo: PRUDENCE CUMING ASSOCIATES

Steve McQueen, British Pavilion, 2009 Photo: © The British Council, Photography by Prudence Cuming Associates

Steve McQueen, British Pavilion, 2009 Photo: © The British Council, Photography by Prudence Cuming Associates

Steve McQueen, British Pavilion, 2009 Photo: © The British Council, Photography by Prudence Cuming Associates

Fresh from winning the Camera d'Or at Cannes last year for his film Hunger, Steve McQueen has created a work for the British Pavilion at the 53rd Venice Biennale as quietly touching as any I've seen in the 24 years I've been covering the event. In Giardini, his camera explores the public gardens in Venice during the winter months when the international fairs devoted to art and architecture have closed, the crowds have gone home and animals, insects and local people reclaim the abandoned gardens as their own.

At one level the work belongs to a tradition in visual art of representing Venice out of season – the backstreets, poverty and sexual opportunity most tourists don't see but which fascinated Whistler, Sargent and Sickert. McQueen's often static camera lingers on rubble-strewn avenues leading to closed pavilions illuminated by moonlight. It homes in to look at worms and beetles from close to, with each shot as carefully composed as a still photograph, and the pervading silence broken only by the peal of church bells and the occasional roar of a crowd from an unseen sports stadium.

What makes Giardini a work of visual art and not a documentary film is the way McQueen manipulates and enhances reality. What we first take to be a pack of wild dogs foraging in the rubbish are actually superannuated greyhounds destined to be put down now that their racing life is over. Out of the shadows of rustling trees on a rainy night a figure steps under a street light to embrace another man in what looks like a furtive homosexual encounter. Two tense young men waiting in the darkness could either be cruising or waiting to score drugs.

So when the lights and the glitz move on – to Miami, New York, Istanbul or Sydney – the gardens belong to the marginalised, redundant, dispensable and dispossessed – the same people this most compassionate of artists has returned to again and again in films about African miners, IRA fanatics, and British soldiers killed in Iraq.

This year, the US won the Golden Lion for best national pavilion with a retrospective of the work of Bruce Nauman, the most influential artist of his generation.

If I had to pick a favourite work from the films and sculpture on view here and in two off-site locations, it would be a shop sign made in 1967 that Nauman first hung in the window of his store front studio in New York. It's a multicoloured neon piece in the form of a spiral of words that say "The True Artist Helps the World by Revealing Mystic Truths" – a sentence in which every single word is debatable. What is a "true" artist as opposed to a fake one? What is a "mystic" truth and how does that differ from truth of any other kind? What is truth and how does true artist reveal it? I could go on.

Nauman's work confronts head on the question of whether art has a function or purpose other than to delight – a debate between the Art for Art's Sake of Flaubert and Nabokov on the one hand and, on the other, the belief of Harold Bloom or F R Leavis in art as a guide to how to conduct our lives. And what is typical of Nauman is that he doesn't ask, he tells you what the true artist does – and dares you to disagree.

A sad fact about the Venice Biennale is that the national pavilions are usually the least interesting part of it. You could skip most of the Giardini and not miss a thing.

My own highlights include Liam Gillick, the British artist in the German pavilion, showing a sleek, modernistic construction in unpainted plywood that for elegance of design more than stands up to the bone-chilling splendour of the pristine white spaces around it. Only after you've admired its abstract beauty do you learn that it is in fact the artist's own kitchen (minus the appliances) but stripped down to its bare bones to reveal its intrinsic beauty – the only clue to the joke being the presence of a animatronic model of the family cat seated above a cupboard.

Michael Elmgreen and Ingar Dragset won a Golden Lion for curating a lively show about collectors in the Danish Pavilion but I must admit the highlight for me was the sight of a hyper-realistic statue of a collector lying face down in his swimming pool, like William Holden at the beginning of Sunset Boulevard. Clearly collecting doesn't buy happiness.

I was also smitten by Shaun Gladwell's films in the Australian pavilion, but I must save that for tomorrow.