This episode of the Outside Podcast is brought to you by Victorinox, makers of the original Swiss Army knife.

You know the one. Red and metal.

For all the kinds of things you don't think about until you really need them.

Tweezers, scissors, screwdrivers, even a corkscrew.

Can you imagine if you carried all that stuff like in a big bag all the time and just had

everything anyone needed whenever they needed it? You'd be known as an obsessive, but people would like you. With a Victorox Swiss Army knife, you can

be that guy, without being that guy. Be ready for anything. Carry it in your pocket.

Go to Academy.com to shop for your Victorinox Swiss Army knife. This is the most delicate. Each May monarch butterflies move north

from their wintering grounds in Mexico, arriving in backyards across the

country, a flurry of bright orange that announces the coming of summer. the some flying 3,000 miles on up drafts and air currents.

Scientists have pretty much always known that butterflies flew south in the winter,

but for a long time where the butterflies went to spend the winter was a mystery.

Then in the early 70s a team of scientists followed the monarchs path to the Sierra

Madre Mountains in Michuacan Mexico.

Here's a Nova documentary from the 80s.

Having crossed half a continent, tens of millions of butterflies converge toward a pinpoint on the map of Mexico.

A 30 by 50 mile area of high mountains and

Spanish colonial towns.

Monarch butterflies are actually the only butterfly that migrates both north and south. In the west they move up and down the

Pacific coast or go to Colorado over winter in California. In the eastern U.S. though, they travel from as far away as Canada and New England to cluster in basically this one patch of forest.

At least for now.

The monarch butterfly was officially designated as endangered by the International

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