I was so hoping that I could lead off this post about insects with a giant weta. It would have been awesome to hold and photograph this enormous cricket-like beast in my hand, to heft the world’s heaviest insect, found only in New Zealand. But that privilege will have to wait until I can get to Little Barrier Island, the only place they are found. Meanwhile, you can check out a story about them here: http://www.themarysue.com/record-breaking-giant-weta/
I did encounter some other weta – more on their terms than mine. Dan and I took the ferry over to Mantiu Somes Island, a preserve that sits in the Wellington harbor. Biosecurity measures are extra-stringent here and include not only bag checks for rodents and insects, but also examining one’s shoes for weed seeds and other contaminants. It is host to many species (like the spotted skink below) whose numbers have been diminished or disappeared entirely from the mainland due to rats, cats and other predators.
The island has none of the largest weta species, but it does have a thriving population of tree weta (Hemideina sp.), somewhat smaller – though still impressively large – cousins. Tree weta like to crawl into holes and hide in dark places during the day. To allow visitors to view them, nature preserves have created “weta hotels,” structures cleverly built of hollow log sections hinged to allow them to be opened, with weta-sized holes the thickness of a finger leading into plexiglas-protected chambers. When the hotel is closed and dark, weta climb into them, and when the logs are opened, you get a murky view of the weta huddled cozily together, safe here from the spotted skink or the hands of predatory paparazzi like me.
An insect that has, in contrast, been super-abundant recently, is the cicada. Actually, I am certain that there are several cicada species sounding off in a deafening daybreak-to-sunset chorus, but I have been able to spot and photograph only three. I’m still not sure of their species, but I am in full agreement with the Maori word for one of the common chorus cicadas, kihikihi wawa – wawa: “to roar like the sound of heavy rain.”
At home in Maryland, the cicadas that emerge annually are not nearly so abundant and raucous, and when I first heard this, I wondered if New Zealand had something similar to our 17-year phenomenon. Apparently not; people regard this as a typical late-summer event, perhaps heightened by the unusually hot, dry conditions, and hardly seem to notice. One radio program did look into it: http://www.radionz.co.nz/national/programmes/ourchangingworld/collections/bugs/cicadas
I’ve started carrying earplugs when I know I’ll be walking in the bush.
While cicadas dominate the sound waves, butterflies and moths typically catch my eye more than any other insect. New Zealand has around 2,000 species of butterflies and moths, and has the highest percentage (90%) of unique native species in the world. 68 species were introduced after Europeans arrived. From what I have observed, the ubiquitous cabbage whites and monarchs top this category, but native yellow admirals and coppers are also plentiful.
I have been missing my moth-luring sheet/light setup here, as I’m sure I could find a number of interesting species that way; otherwise, the moths have been elusive. One that we will probably never see in Maryland is the cabbage tree moth (Epiphryne verriculata), whose caterpillar feeds on the leaves of the palm-like cabbage tree, Cordyline australis. Though I photographed this moth as it rested exposed on a window, it can camouflage beautifully by placing itself in alignment with the dried leaves of the cabbage tree.
Arriving in New Zealand in the summertime offered the chance to see plenty of pollinators still in action. They appear to include only a few species – although some may, like moths, be nocturnal. I discovered that the bumblebees I have seen, which are in nearly every flower, were intentionally introduced to the country in order to pollinate another introduced species, red clover, used for agricultural purposes. The steel-blue ladybird (Halmus chalybeus) was also brought here intentionally from Australia to help control scale insects.
The idea of bringing in insect species to aid ecosystem services like pollination is not new, but in a place like New Zealand that has seen many introductions gone awry, it’s interesting to think about possible ramifications of such moves. One of the Fulbright students whom I met at our orientation last week is here studying dung beetle introduction. Large, grazing herbivores like cattle and sheep were introduced to this place with no natural evolutionary ecosystem capacity for dealing with their production of large amounts of dung, so dung beetles imported from other places are being tested as an option. I’m sure everyone will be riveted waiting for the results of this experiment.
I’m still not confident of my insect ID’s yet, so I will add them in gradually as I learn them. Missing my go-to online North American identification guides like bugguide.net, I was reminded during a school tour at Zealandia of a great citizen science resource for all species that is available world-wide: inaturalist. In New Zealand, it goes by the name of NatureWatchNZ, and I have started contributing some observations that I hope will yield both accurate ID’s and records of species locations.