[Hong Shee]

Hong Shee asked the Naked Scientists:
   
Hi naked scientists,

With regard to the article you recently posted on the Predator-Prey role reversal of the Epomis beetle larvae and amphibians, it would be interesting to know if it can be used to control the cane toad population in Australia?

Wouldn't it be great if we could use the larvae as a weapon to irradicate the cane toad problem, with little or no ecological effects to follow?

What do you think?

[chris]

That's a great idea, but let's consider the situation a bit more widely for a minute...

The cane toads are a nuisance because they are an introduced species with no evolved natural predator; they are also toxic to the native carnivores.

But the Epomis beetles are natives of the Middle East. So you'd be introducing another non-native to combat a fellow non-native. And it would be be unlikely to target just the invasive species, so the already-threatened native amphibians, suffering from the effects of competition from cane toads, might then end up in double-jeopardy!

Therefore I think one would need to look very carefully into this before potentially upsetting an already- overturned apple cart!

Chris

[Don_1]

100% agree with that Chris. The introduction of a natural predator to control an introduced 'pest' species might seem like a good idea. But just suppose the introduced predator finds a native species which is easier to catch, more nutritious and/or more abundant. You could end up doing more damage to the ecology of the region and may not have any effect on the species you are targeting.

Japanese Knotweed has been a problem in the UK for many years and is estimated to cause £150m of damage to roads, buildings etc annually. It is also an invasive species which threatens indigenous species. Only after extensive research and testing, did DEFRA (Department for the Environment, Farming & Rural Affairs) give permission to introduce a psyllid (Aphalara Itadori) into Britain to combat this introduced species. It was established that the nymph would not attack any other species and deprived of the Japanese Knotweed, the nymph would not morph into the adult insect.

As far as amphibians are concerned, it must be remembered that many species around the world face a very serious threat from chytrid fungus. Any interference with any species of amphibian must be given the most stringent scrutiny before we do any more to threaten virtually this whole phylum of species.