Regular readers of the blog will know that every fortnight I write a special blog on something science related that I’ve either visited or been involved with. Some of you may have already realised that I like to listen to rock/heavy metal music and unless you’ve got that up to 11 you’re doing it wrong. So I thought I’d mix things up a bit to make you all aware of a paper I stumbled across thanks to the wonderful powers of Twitter.
Recently a team of researchers tested how the ‘AC/DC Hypothesis‘ can affect ecosystems. Now we all know that guitarists such as Angus Young and Slash can use the humble guitar to create holy music but in real life what does this actually simulate? To a bee or an aphid AC/DC isn’t as harmonious and instead replicates the noise that a busy road may create. Noise pollution is recognised as an increasing threat for wildlife, having impacts on amphibians, reptiles, birds and bats for example. Most studies I’ve seen in the past only focus on the direct effects of loud noises whereby an animal hears the noise and is affected. Animals belong to complex ecosystems and a spaghetti of food web interactions. So noise pollution has the operational opportunity to generate indirect effects that may affect entire plant or animal communities.
The study looked at that the harlequin ladybird (Harmonia axyridis), which of course is a huge menace in the UK being an invasive species and eradicating our native ladybird species. Ladybird are important predators of pests such as aphids which may cause damage to agricultural crops if not kept in check. The team investigated whether or not noise pollution would decrease lady beetle effectiveness at controlling aphids. Another factor also being looked at was with the predators being less effective, would the aphid populations explode? Sounds were played through computer speakers at 95-100 decibels which is approximately equal to a lawn mower (so enough to annoy the neighbours with your headbanging antics). Ladybirds were affected by the the rock mix even when played at the same volume as country or folk music treatments. Whilst I think Back in Black is AC/DC’s best album to date, the ladybirds did not. Whilst it was playing, it cut the amount of aphids being eaten during a 16 to 18 hour period almost in half. It seems that to a ladybird rock ‘n’ roll was indeed noise pollution and indirectly benefited agricultural pests. The study also looked at the effects of plant growth affected by the music but found no real effect which leaves us with one troubling issue.
It seems that AC/DC were in fact incorrect, loud rock music does have ecological effects as a noise pollutant. In the real world though, how often is rock music blasted out in an area where wildlife is likely to inhabit. Yes it happens in people’s gardens and at music festivals but the effects are likely negligible. The most interesting finding I think the study found was that rock music imitates anthropogenic noise such as construction and busy roads. Now I’m not going to stop blasting out my music as loud as I can just to save a few insects, especially when I’m in an enclosed environment like my house. However, I think I’ve come up with a radical solution to solve our harlequin ladybird problem here in the UK. Find the areas where they are attacking and out-competing our native species and blast them with the power of heavy drums and distorted riffs. Of course there may be other consequences to our native species but as long as we are having an effect on the harlequins, it’s all good right?