Mass Exodus – Christchurch, New Zealand Trip #1July 1, 2010 at 6:08 pm | Posted in itchy backside | 4 Comments
Tags: Animals, Bugs, Nature, New Zealand, Photography, Travel
Itchyfingers did our first driving trip around the South Island of New Zealand in early February. It was late Summer so the weather was turning cooler, generally comfortable except when strong winds blew. The first day when we reached Christchurch, we strolled around for lunch, did some casual window shopping before getting lost and found ourselves at the Botanic Gardens, which we had intended to visit anyway. :p It turned out to be a very fruitful and interesting short visit!
We were walking around taking photos when we caught sight of this fruiting tree…
Hmmm….don’t see these in Singapore…wonder what trees are these?
A closer look at the fruits…oooo….spiky fruits! How interesting…
The fruits and a split-up inner shell that once contained a nut…
Size comparison using my shoe, which looked so new here…This one
revealed a softer skin under the spiky outer layer
We gathered some fallen fruits and a leaf for a ‘group shot’…haha…then
we noticed the nut inside looked so similar to those roasted chestnuts that
we eat….Just when we were still wondering, something on the ground
caught our attention…Can you see anything here? Hint: it’s on the top
right-hand corner…look carefully…
Can’t see? Nevermind. Here’s a close-up…
An insect moult. To be specific, a cicada moult…
Cicadas are nocturnal and you probably heard them more often than seen one.
A cicada we photographed at Sungei Buloh Wetland Reserves. Cicadas have
large compound eyes situated one on each side of the head. They also have
three very small glistening simple eyes (ocelli) on the top of the head. Ooo…
looking at this photo now, could that little red dot on the forehead be one
of the simple eyes?
Once we spotted this moult, we started to count more on the ground…and then guess what…
We looked up the tree and gosh…we lost count! They were all over the trunk!!
It was such a spectacular view that we wanted to get a more dramatic photo. But we couldn’t do so without our faces touching and lips kissing the moults if we were to lower ourselves closer to the ground or the trunk. :p
This sight reminded us of what we had read about cicadas emerging from the ground. I am sure many of us have also read and heard of one species of cicada that stays underground for as long as 17 years before emerging from the ground to moult. So I presumed these should also be crawling out from the ground and up the tree before they shed the old skin and flew away? Wow! Wonder which species were these and why did they only choose this tree for their moulting process…but then when we looked around the vicinity, we were so surprised to find yet another whole groups of cicada moults on a few other similar trees!
There were some here on this less dramatic photo…
And some more on this other tree! Each tree had these discarded shells
“decoration” on them to a height of more than 1.5 metres or so…So you
could imagine the sheer numbers of these cicadas rushing up the tree for
a nice spot….
The late evening sun made the already golden coloured moult glow…
Most of these shells were very complete, as if a real cicada was on the trunk…
Do you know that in China, these moults are used to make miniature
monkey-like sculptures? Called 毛猴 (or literally Hairy Monkey), they are
made from the cicada moults and other traditional chinese herbs…See here
for some of these 毛猴 sculptures. Interesting, but I don’t think I wanna
keep it as an art piece at home… hahah
We saw these moults before we peeped into the changing room of
a grasshopper back home some time later, so we didn’t notice it then.
But now we know it is the breathing tube…
Back home, I search around for cicadas moulting in New Zealand, and found this information from this site. “On the under surface at the rear of the abdomen the female cicada is equipped with a short ovipositor, a spear-like appendage with a flattened diamond-shaped point, used for making elongate slits in the stems and leaves of plants in which the eggs are laid, four or five to a cavity. Some species of cicadas at least are thought to lay several hundred eggs each. Upon hatching, the minute larva escapes from the egg chamber and descends to the ground. In the ground the larvae, which possess a cylindrical proboscis and large claw-like forelegs, grows through several moults. The New Zealand species are believed to feed on the juices of plant roots – few observations, however, have been made. The last stage before emergence of the perfect insect is the formation of a nymph, rather similar to the larva but with rudimentary wings and harder skin. In late spring and summer the nymph emerges from the ground, climbs some distance up bank, grass, stem, or trunk; the skin splits on the back of the thorax and the adult insect emerges with wet crumpled wings and soft skin; the wings dry and harden and the adult insect finally flies away. Although there appears to be some periodicity in the appearance of large numbers of M. cingulata, too little is known of the life history of the New Zealand cicadas to express an opinion on the duration of the life cycle.” (For an interesting read on the life cycle of cicadas, read here.)
No mention about the kind of tree they choose though…Maybe this species of tree was where the Mummy Cicadas laid their eggs on…hmmm…so what tree was this?
The site said, “In its final moult, the cicada changes from a drab, ground-
dwelling nymph to an often colourful, energetic, winged adult. The exoskeleton
is entirely shed, including the linings of the breathing tubes, which can often
be seen poking out from the cast skin. In areas dense with cicadas, dozens of
skins can be seen on tree trunks.” Can you see the breathing tubes more
clearly now? 🙂
So, Itchyfingers were there at the right season…Well…if only we were slightly early…imagine being lucky enough to witness the mass exodus…but, that would usually happen at night time. Now we could only pick the empty shells…hahah…
My curiosity was so strong that I finally found the name of that tree after quite a long time searching online. We were right that it belongs to the chestnut family. So, it is called the Horse-chestnut (Aesculus hippocastanum) or Conker Tree, native in the southeast Europe and widely cultivated throughout the temperate world. But unlike the chestnuts that we normally eat, the nuts of these Horse-chestnuts are slightly poisonous.
Taking one last look at the moults, Itchyfingers proceeded to explore the
rest of the Botanic Garden. Really glad to have been able to see this
spectacular work of nature!
Also see related post:
> A Peep into the Changing Room