The Ladybug Love-In

Can you see the rusty patches on this fallen redwood tree?

It almost looks like some sort of disease, doesn't it?

Except it's moving.

They're ladybugs.

Thousands and thousands of ladybugs.

For ladybugs all over the country, this yearly gathering is a once in a lifetime event.

The culmination of ladybug existence.

It starts as the cold weather sets in wherever they live...

Until now, these California ladybugs have been feasting on aphids.

But when the weather turns, this feast of aphids will disappear.

That's a signal for the ladybugs.

Time to go.

They lift up, like little helicopters - over the garden, over the city.

Up high, the wind takes over, blowing them toward the nearest mountains.

Year after year, ladybugs converge in the same spots.

Which is amazing, because these particular ladybugs have never been here before.

Scientists think previous generations left pheromone tracks - chemicals secreted through their feet - like a trail of breadcrumbs for them to follow.

By late fall, it's on.

Their rusty color is a warning to predators: we taste terrible.

For the first time in their normally solitary lives,

they find themselves in a ladybug bacchanalia.

They're all over each other.

As winter creeps closer, they'll hunker down together in tree trunks, and underground to hibernate.

When spring comes, they'll emerge, and take care of any unfinished business.

This is their last chance to mate.

They only live a year.

And then, they'll go home. Never to return.

Next year, another generation of ladybugs will follow in their footsteps.