Sam Judd: Should we import foreign bugs to help our environment?

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New Zealand has a rather embarrassing history of bringing things into our country that are intended to help us, but end up being a hindrance.

After we brought in rabbits for food and sport in the 1830s, we realised that they cause massive damage to the land.

In an attempt to control the bunnies, stoats were introduced. But now these weasel-like creatures are considered 'public enemy number one' to birdlife by our Department of Conservation.

When it comes to plants, we have introduced all sorts of weeds that now cost hundreds of millions of dollars to attempt to control. Trees such as wilding pines and eucalyptus have very strong oils that come off their dropped foliage which make it very hard for native plants to survive.

Wattles and privets are other pest trees that grow so fast in New Zealand that they shade-out natives, meaning they can't grow.

And who out there remembers the story of the Scotsman who thought it would be a good idea to bring in gorse to make hedges?

We all know what happened there.

But now, we are again seeing plans to introduce controls to help our environment. A proposal to introduce dung beetles to reduce the harm of farm effluent, has had the green light and yesterday, the Te Ao Turoa Environment Centre in the Manawatu began to release them onto farms with funding from the Manawatū River Leaders' Forum.

Now this all seems like a great idea. Landcare Research explains that Dung beetles literally reduce harm from effluent by eating it and storing it in the ground instead of letting it get into the waterways. This service, whilst not glamorous, could be a key measure to improve our ability to swim in the rivers, but then, could it pose a risk like the stoats did?

Back in 2008, Landcare Research biological control researcher Hugh Gourlay said that public fears are always high when any planned introduction is discussed, he says, but he had no fears of the beetle causing harm to New Zealand.

"We would look like complete idiots if it did. We'd never apply to introduce anything that had any risk associated with it," he said.

Another idea currently on the table is to introduce a Korean strain of the Calicivirus to kill rabbits. Scientists say that the RHDV1-K5 virus could kill up to 30 per cent of the wild rabbits that plague farmland.

For some (completely non-scientific) reason, I feel a little bit sceptical of the idea of introducing a disease, so I just hope we don't rush into it if there is any risk of problems.

You may be aware that I am all for anything that could work to improve our environment. And science today is obviously far advanced compared to when we made these blunders in the past.

But I would love to pose three questions: what other bio-controls are out there that could help our environment? What do you think about this? And how confident do we have to be that these ideas will work?