英语听力：什么害死了我们的蜜蜂—9

And here it is, the flight of the humblebee. This is what's called its exploratory path. The routine takes its circles around the hive for the first time. Over several days it's built up a mental map more than 10 square kilometers around the hive. The radar allows us to see this with an unprecedented position. -What's been found is that they are all ** very, very efficient to explore the biggest area with the shortest time and shortest energy of those efforts.

I'm here to see Stephan's latest experiment. He wants to find out if the viruses carried by the Varroa might will affect how the bees fly, and that's important because if they can't navigate properly, some of them will die.

-So what we have, we have a colony in there, and in that colony live bees which have various levels of diseases. These bees only live in that cage. They don't know the landscape around.

The bees here are all healthy enough to fly. The question is does the virus affect their exploratory flight.

-So here you have a not-quite-so-willing volunteer nearly dropped there.

-Hey, Jason, the bees are quit, have a look.

-Here she goes.

-OK, Jason, she's out, she's out.

-Warming up a bit.

-Here she goes.

-OK. She's off, she's off, Jason.

-OK, one bee's flying, flying away from the cage.

-She's out there, so you definitely saw she take off, did you?

-Yes.

-She's leaving a loop. She stops, she stops.

As bee No.1 goes to ground for a while, it's my chance to head to the radar station across the field.

-Hey, Jason. How's it going?

To the bottom-left of the screen a red spot marks the position of the hive just over 200 meters from the radar.

-200 meters now.