If you are willing to get close, you may spot one of these beasties, seen on the left, about 3 mm across,
and looking like a silver cashew. This is a thieving spider called Argyrodes. They seem to do quite
well in the webs of Nephila. By an odd chance, they are in the same family as our most dangerous
spider, the redback, which can be found in sheltered corners in our plant nursery, and also in the watering points
that we use on the "Oval". Stay away from light blue lids in the ground!
Are you at risk from redbacks? The advice seems to be that you won't end up dead, but you will wish that they had killed you. Here's some amusing research on these relatives of the black widow and the katipo of New Zealand.
Three of our more unusual spiders, the St Andrew's Cross spider on the left, Austracantha minax, and the oddly-named Backobourkia sp. on the right.
Anybody who has ever looked at a trout fly knows those things are pure fantasy, but in winter,
fantasies can be sees flying at the Third Quarantine Cemetery, and also near
the southern entry to the Hanging Swamp track.
Our love affair with these curious joys began when some of my fellow Wednesday volunteers encountered strange floating white fluff at the cemetery in 2016, and they weren't seen again until 2020, but keep an eye out. They will land on a gloved hand, if you offer it to them. If you look closely at the flying fluff, each flake is an insect.
These shots on the right are some images taken with a bit of artifice which is explained
further down: I don't like killing things to look at them.
While they are called 'bird of paradise flies', and even seem to have two wings (like flies), these aren't true flies at all. The males have four wings, but the hind wings are greatly reduced. The males (and only the males) have long waxy filaments on their abdomen, and the ones I have seen are about 20 mm long.
These are true bugs, Hemiptera, members of the genus Callipappus. To gardeners, they are scale insects, beasties that suck sap from plants like Xanthorrhoea and Banksia. The adults emerge in the autumn, and should be visible until June. I am still searching for the females, which must be there: if you want to join the search, Google Callipappus and look for images.
I decided to use a simple kit to chill animals and photograph them with my phone, and because
this method can be used for many insects, here's how to do it.
I put a 6 cm Petri dish, weighed down with a 50 cent coin, in a 10 cm Petri dish with water in it. This goes in the freezer, later the coin goes back in my pocket (it's the same one you see with the snail below) and the insect goes in the dish. So if you think you see snow at the Third Cemetery on a warm May day, look again, but these things are much too magical for anybody to feed them to trout!
Small advertisement for myself: There are more methods like the insect chiller in my
Looking at Small Things, which you can
buy
from Amazon or get
for free from this link.
The same sort of chiller kit comes in handy when you are looking at ants. To the best of my
knowledge, we lack any of the big, nasty bullants, something over 30 mm long, but if you see
one of these, go the other way!
While I have used this rig to photograph them in the past, I know what I am doing, and you
are better off leaving these monsters alone.
Ants vary in size from almost invisible, not much more than 1 mm long, to claimed lengths of up to 40 mm for bull ants, though 30 mm is more likely. Warm northern Australian climates, average 150 species of ant per hectare, while in cooler southern climates, there may be 75 different species in each hectare.
I haven't spent much time looking at our ants, but there are a lot of them, and they make
some neat sandhills. The easiest ones to look down on without bening 'nipped' are the ones
that sit under the steel tracks.
Aged seven, I was given a book called Beetles Ahoy!. I read about ant lions there
and fell in love with them. Family Myrmeleontidae (Neuroptera) to entomologists, these
are the larval stage of lacewings. They dig neat holes.
The name is a misnomer: they aren't lions, as anybody can see. More importantly, they don't always eat ants: I have seen one catch and presumably eat, a small weevil.
Any loose material like sand has a natural angle of rest, as you can see in the jar above. This is the steepest angle sand can hold without tumbling down. Sand dunes, sand heaps and sand banks are all limited by this angle. So are wells dug in creek beds.
This angle shows up in sandstone cliffs which contain fossilised sand banks, and you can
see these all over North Head. The best accessible view is from the lookout off the Fairfax
Track, but the example here is from the almost inaccessible
Old Man's Hat.
So sand has a position of maximum stability. Ant lions rely on this. They dig conical pits in the sand by burrowing into the sand, and flicking sand up and away with their heads so the sides settle at the angle of rest. Then the predator sits hidden at the bottom, waiting for something to fall in.
Anything going over the edge dislodges sand and tumbles down. As it tries to scramble out
the ant lion flicks the fallen sand out. This undermines the side which start to slide down,
while some of the flicked sand knocks them down. The prey slides down as well.
Once the unlucky animal reaches the bottom, the ant lion seizes it in its pincers and starts sucking it dry. In the end, it flicks the empty husk of the prey out of the pit.
Ant lions are all over North Head, but you have to know to look for a small conical pit, 1-3 cm across in dry sandy soil. The soil may be close to one of the gum trees that kill grass, inside a hollow tree, along the edge of a building or under a rocky overhang. Sometimes, you can even see ant lion pits, right out in the open.
At times, and for assorted reasons, I keep some as pets. A dish like the one on the left
is all you need: just add ants-or weevils.
Cockroaches frighten a lot of people, but most of these flat oval scavengers recycle dead material, so they are useful. Most people only know the few species that infest houses and drains, but there are more than 400 native cockroaches in Australia. They live in the bush and they are never pests in the house.
Here's some information from the Australian Museum.
Centipedes are carnivores with a venomous bite, but millipedes are vegetarians; centipedes are flat
while millipedes are usually cylindrical; and only millipedes can roll themselves into a spiral.
The easiest way to tell the difference is to count the number of legs on a single segment. Both
can be found in leaf litter, or under logs and bark, but millipedes can also be found wandering on
damp lawns. The one in the lower half of this image was found near the Memorial Walk, on a stone.
The upper image shows how millipede legs work in waves: each asterisk marks a separate wave. Sadly, the one I found was in poor condition. Millipedes don't bite, but I was burnt by a millipede once, when I was handling it. I looked it up and read that they secrete hydrocyanic acid, which would be a good defence against predators. Over the years, I have cited this fact in classes and lectures.
Always check your facts, because when I was writing about a "dose of millipedes" for another book, I learned that this was only partly correct. They produce a mix of hydrocyanic acid, along with quinones, alkaloids, ketones, terpenes, esters and phenols.
I really ought to get back on the topic of centipedes. I think I have seen a couple, but I have no photos.
My advice is to wave at anything with lots of legs and leave it alone.
Look again later, if you want more insects!
This snail turned up, one rainy day, as we walked along the memorial walk.
This has river pebbles along each side, and to reduce wear on the pavers, an old soldier sweeps
the pebbles off, once a week, but my wife and I push the interlopers away with our feet, gently
and non-scrapingly. That was how we spotted this native snail.
This is the first one I have seen there, but there are probably more land snails around...
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The page was first created on 27 July 2020, and was revised on 1 August 2020.