The false katipō females don't have the distinctive orange stripe on the back as does the native katipō. Photo: Supplied / James Roberts
A group of Kiwi researchers have held a spider Olympics to get to the bottom of exactly how much of a competitive advantage introduced false katipō have over New Zealand's native katipō.
The false katipō are actually black cobweb spiders, originally from South Africa.
Lead researcher James Roberts - who is pursuing his conservation biology PhD from Sydney - told Saturday Morning the false katipō appeared to be more adventurous than its Kiwi counterpart.
"We had the spiders traversing a maze, we had them climbing poles, and running down a sprinting track while being chased with a paint brush."
The non-traditional "olympics" included a series of tests common in spider research and showed a possible frontrunner.
"They both climbed the pole with the same speed and tenacity," Roberts said.
"But it seems as if because of the facts that the false katipō was more exploratory and bold perhaps they can have some sort of advantage in reinvading sand dunes that have been disturbed by severe weather events or four-wheel driving or something faster, allowing them to potentially out-compete the katipō."
The false katipō doesn't bear the distinctive orange stripe on its back as the native katipō do, but the females are both black and shiny.
The males, the subject of the research, are about one sixth the size of the females and are white with green and yellow stripes.
Roberts said the fact the introduced katipō were bolder was potentially associated with the invasive biology.
"Invasive species have select advantages over native species generally and that's why they're so successfully invasive.
"The false katipō is worldwide spread. It just seems to be doing really well at getting into these new areas."
Before comparing the spiders, Roberts' team needed to catch the katipō first.
That was done relatively quickly according to Roberts whose team worked with the Shorebirds Trust at Mangawhai's Tara Iti Golf Club to collect the two species at nearby Te Arai Beach, where a healthy population of the spiders thrive.
Asked whether there should be any concern about the false katipō's potential to invade, Roberts said not in a physical sense.
"They're not going to cause you any harm invading your home or anything like that, and they're probably already there to be honest, but in the sense for our native species, we don't want to see them being out-competed, especially by a South African rival.
"So yes I think we should be concerned by that. The katipō is a pretty awesome species and to see it disappearing is pretty sad."
Roberts said the researchers could not yet say what effect the false katipō was having on the native species so there was no suggestion of culling the invaders.
Instead the focus was to look after the sand dunes, which would help all kinds of species.
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