David York’s The Beetles are Coming isn’t the first documentary to stir fears of a cataclysmic destruction caused by climate change.

But what marks this dystopian vision of present-day environmental catastrophe was its subject’s refusal to cooperate for its close up.

York, the writer, director and producer of The Beetles are Coming, recalls how quickly the CBC commissioned for its The Nature of Things strand his investigation into a deadly mountain beetle infestation overtaking British Columbia’s pine forests.

It’s unthinkable: the province’s prosaic pine forests are dying and being left brown and barren at a dizzying pace.

And all because of tiny beetles.

But capturing on camera an exotic pest barely larger than a pinhead for The Beetles Are Coming threw up a host of visual challenges, York recalled.

“It’s tricky. The challenge is the mountain beetle is an insect smaller than a grain of rice, and spends all but two days of its life under the bark of a tree, and the two days that it emerges, it emerges on mass, and you can’t really predict where and when it happens,” he explained.

This wasn’t like approaching, composing and capturing honey bees flitting from flower to flower using macro camera lenses.

Because pine beetles live under thick tree bark, York and his team tracked north from Missoula, Montana into Canada to find forests under active attack as bark beetles surviving winter briefly emerged to find new trees in which to lay their eggs.

“If you miss the two days, there’s no other moment. And we knew we had to visualize an active swarm,” York observed.

His documentary team did find their attacking mountain beetles with a dazzling feat of insect photography.

York’s extreme close up zoom shots captured living trees attempting to repel roly-poly beetles by opening its sticky resin ducts like medieval castle defenders pouring boiling oil on attackers.

“That moment is pretty icky,” the filmmaker said of footage showing beetles burrowing through bark boring holes, and chewing in a side-to-side motion, as stored resin rushes out to pitch them back.

The invading insects use their tiny legs like paddles to push the resin aside until within a day the tree bleeds itself dry and dies.

Not exactly the magnificence of salmon swimming upstream in a spawning frenzy.

But The Beetles Are Coming is no beautiful nature documentary showing ocean whales or jungle lions in all their glory.

York instead offers a sober warning of ecological disaster.

In effect, creepy crawlies riding the mild winters and hot summers that global warming brings now threatens forests countrywide on which we depend for oxygen, tourism and forestry.

In the past, warm winters and dry summers during periods of ecological balance would see a growing beetle population attack and reduce the number of older trees in B.C. forests to allow younger trees to grow.

Then normal weather would return and cold snaps would kill most beetles and keep their numbers in check.

Now global warming has allowed the beetle population to explode, overrun forests in Alberta, and leave scientists unable to stem their eastward expansion.

“There’s no question that as soon as the mountain pine beetle was able to cross the Rockie mountains and establish in the northern boreal forest east of the Rockies, the stage was set for the beetle to cross and go all the way to the Atlantic,” York explains.

“The only thing that can limit the beetle is the climate. We are in a period of warming and the conditions are there for the beetle to keep going,” he added.

The Beetles are Coming will debut on The Nature of Things on Thursday, April 4, before repeating on CBC News Network on Saturday, April 6.

Photo: Signs of the beetle devastation in British Columbia, by J Mitton courtesy CBC