And this is the sort of thing they can do. This bee is suffering from deformed-wing virus. You can see pretty easily what's happened to it. But what makes Varroa might so sinister is that it can cause something much more difficult to spot.

-The viruses carried by Varroa might can have all two obvious, devastating effects, but in reality these are only seen in extreme cases. More worries researchers is now that these may be just a tiny minority of all infections, and many more bees apparently healthy may be infected by viruses in less visible ways, which are just as devastating for the colony.

What they're trying to find here is what happens to these infected bees, once they leave the hive. To do that, they've invented something pretty remarkable.

-Jason, it looks like we've got some military astronaut station here. What is it?

-Well, this is a specially designed radar that we've developed that allows us to track the flight path of the bees, once they leave their hive. You can very easily study what happens when bees come back to the hive and leave, but what happens when they are on their foreign flights some distance away because it is always a great challenge to study, and it was in so we developed a system, such as this radar, that we are able to accurately track their flight paths over distances of hundreds of meters or even up to a kilometer.