Eco-docos don't have to be accompanied by a doomsday voice-over. Those by film-maker Taggart Siegel come with an infectious enthusiasm for their subject. He likes to pick subjects that are tangible - last time it was organic farming in a select community in Illinois, this time it is bees.

"We are so over global warming, but I don't think we are over bees," says Siegel, who splits his time between his hometown of Portland, Oregon and his bird sanctuary in Lyttleton, Canterbury.

He tells stories with heavy environmental themes through the eyes of endearing characters - such as John Peterson, the eccentric organic farmer from Illinois who fronted Siegel's award-winning 2005 documentary The Real Dirt on Farmer John.

Siegel's latest labour of love, Queen of the Sun, documents the demise of bees through the worried eyes of those who keep them.

Bees are not one of the world's most-loved creatures. In fact most people grow up fearing them for their sting and unfortunate yellow and black aposematic colouring, but Siegel says his mission was to help turn that perception on its head, without being too "preachy".

The documentary grew from an article Siegel read in an environmental magazine which quoted Albert Einstein, who once said that should bees start dying, humans would have just four years to live.

"That quote woke me up so quickly," Siegel says. All the evidence is there to suggest that colonies are already rapidly disappearing - commercial beekeepers report losses of between 30 and 90 per cent of their colonies.

Siegel says that's not surprising considering huge expanses of land have been stripped of bees' traditional food sources (diverse plants) as agriculture shifted from the "Old Macdonald Farm" (a range of animals and crops on a smaller section of land) to intensive crop farming (of soybeans and corn). The hedgerows that once provided their nectar have been replaced by cold wire fences. Plants they once frequented (like tomatoes) have been genetically modified.

Bees are also in the precarious position of having fewer genomes than most insects, which slows their ability to evolve and fight against pests like the varroa mite and pesticides, and adjust to their rapidly changing surroundings.

"Bees haven't had to adapt for about 30 million years, they have been having this beautiful relationship. The bees are the legs of the plant, go into the love centre of the flower to collect the honey, take it to the hive and create an incredible thing we call honey," Siegel says.

And it's not only honey that humans will miss if bees die out, as they pollinate about 40 per cent of our food. If they go, so will blueberries, apples, peaches, melons and tomatoes.

"All we will be eating is bread and rice basically," Siegel says.

Queen of the Sun presents the facts through interviews with some of the world's most passionate apiarists, such as Frenchman Yvon Archard who tickles his bees with his moustache. Sara Mapelli, a beekeeper and a performance artist from Oregon dances with her bees, and among the other colourful interviewees is an Australian beekeeper who Siegel likens to Winnie the Pooh, and several Kiwis, one of whom has passed on his love of bees to his three daughters.

"I don't want to sound all new agey but I think we have found a new heart. Old-school environmentalism, run by aggressive types, doesn't really work. I support some of them, but I feel the new approach is to get people up to having a deeper appreciation of nature," Siegel says.

And so far, he says the film seems be cutting through some of the environmental apathy that has grown out of a retaliation to "greenies".

In Portland, Oregon, where Queen of the Sun had its first cinema release outside a festival, audiences went on to organise a "tour de hive" where suburban apiarists opened their backyards to people keen on finding out more about keeping their own bees in the city. That built on a wider trend, led mostly by a younger generation, that promotes the backyard of yesteryear, complete with a vegetable plot, chicken coop and now, beehive.

Siegel insists he is not out to scaremonger. "It's really to create a conversation so that we can start preparing, and [ensuring] we don't carry on like this."

And no, he doesn't think humans will die in four years. He expects backlash from commercial beekeepers, agriculturalists and maybe some activists, but the fact remains that the so-called colony collapse is happening. Even little, isolated New Zealand - where the bee population is already threatened by 37 pesticides, and the varroa mite has just spread into the South Island - should be seriously concerned, he says.

As one of the documentary's beekeepers, Gunter Hauk, points out, honey bees are a great indicator species - "their crisis is our crisis".

Siegel is confident that at the very least his film will incite a shift in attitude towards the inexhaustible insects - they don't just bring us the honey we spread on our toast.

"You think you can't look into their eyes very easily but you can. People fall in love with bees," he says.


Taggart Siegel

What: Director of Queen of the Sun: What are the bees telling us?, a documentary in selected cinemas from Thursday