Robyn Williams: So what's that noise? Underwater? Aliens, or what? Okay, let's go to Harvard for the answer, with part-time Ig Nobel ichthyologist Marc Abrahams.

Marc Abrahams: Herrings. This is research that was done by two groups at about the same time, working in very different places and for different reasons. One group is based in British Columbia, Canada, and also part of its team in Scotland. The other group based in Sweden. Both of them were examining herring and their behaviour. What they ended up discovering, both of them, was that herrings make a peculiar sound which comes from farting, and that herrings probably, not certainly but probably communicate by farting. At the Ig Nobel ceremony one of the scientists said, 'Herrings in that respect are not unlike human adolescent males.'

Robyn Williams: This is not the conclusion that they came to in the Swedish government, though. They thought it was something else—what?

Marc Abrahams: The Swedish team got involved at the request of the Swedish government, from on high. The Swedish government suspected, strongly, that the Russian government was sending submarines to spy on them, and even sending submarines in to Stockholm harbour. They put microphones underwater in Stockholm harbour to gather evidence and they got evidence. It sounded like rhythmic, metallic tapping…

Robyn Williams: Click, click, click…

Marc Abrahams: Much faster: click-click-click-click-click, all metallic. And they were convinced that at last we have the evidence, we can get up in public and accuse the Russians of doing this, and just to bolster the evidence we will gather a bunch of Sweden's finest scientists to look at the evidence and write reports saying that, yes, this is exactly what it appears to be. And they gathered scientists from several different fields including two marine biologists. Those two biologists listened to the recordings and they said yes, these are very good recordings. They are not submarines, they are fish, and we're going to go and spend a little time doing some research. We can tell you what kind of fish.

So they pretty quickly discovered it's herrings, and not only is it herrings but these things you thought were submarines, no, they're herrings farting. As a result of that the Swedish government at the highest levels suddenly decided to not get up and make an announcement. And from what I have been told by some of the scientists, this created intense, very angry feelings at the highest levels of the Swedish government. I just was told the other day that one of the highest level Swedish politicians at that time is still insisting that it was submarines, it was not herring. So it sounds like there's some sort of public collision coming at some point down the line, because one of the scientists is planning to write a book about this whole incident.

Robyn Williams: It reminds me to some extent about Dr Strangelove and even the old stories about a flock of geese crossing the radar and possibly leading to the third world war. Were we close to that kind of apocalypse as a result of these farting fish?

Marc Abrahams: As far as I know the Swedish government had no real plans to detonate nuclear weapons on their neighbour, Russia. But whatever they expected didn't happen.

Robyn Williams: Was it a happy occasion, on the other hand, when your two teams of scientists were united at the Ig Nobel? They'd never met before, had they?

Marc Abrahams: That's true. They'd never met. I'm not sure they were even very much aware of each other until they shared the prize, and they met for the first time on stage at the Ig Nobel ceremony. And not only did they both get to give acceptance speeches, all of them got to perform in the opera we had written that year. We had them in a kick-line with a lot of people. And they were surprisingly not incompetent at that.

Robyn Williams: Did they ever reveal to you how the herrings managed to fart so extensively and so subtly as to have a kind of communication language?

Marc Abrahams: Yes, thank you for asking. It's not probably what you are expecting. It's not the kind of farts that mammals would make. It's not coming from the intestines. This is a whole separate system, just channelling air through, and it's almost certainly used, partially at least, for buoyancy. So they will release some of the gases at times to make themselves less buoyant.

Robyn Williams: Yes, they can't actually fart in the classical way, because they don't have buttocks.

Marc Abrahams: You know, all of this thing depends on how you define your words.

Robyn Williams: Yes, and being from Harvard you're very meticulous about this. But finally, you're going to Sweden shortly…is it as a result of this sort of investigation?

Marc Abrahams: Yes, in a couple of weeks I'm going over, first to England and Scotland and then to Denmark and Sweden. I'm going to be meeting up with various Ig Nobel prize-winners and doing a bunch of public shows. And the one I'm most looking forward to is a show we're going to be doing in Stockholm, Sweden, with those two biologists, and I am curious to see who else comes.

Robyn Williams: The prime minister?

Marc Abrahams: The former prime minister I believe it is. And it should be a fun evening.

Robyn Williams: You'll let us know.

Marc Abrahams: Yes. And I'm hoping that of course we'll go out for dinner and enjoy some of that fine herring the Swedes are famous for catching and cooking.

Robyn Williams: Thank you, Marc.

Marc Abrahams: Thank you, Robyn.

Robyn Williams: Gone fishing for herring and a peaceful coexistence. Marc Abrahams is the genius behind the Ig Nobel prizes. Do look them up online. And he's the editor of the Annals of Improbable Research.