Castle Hill is an immense mass of pink granite rising above the city. Beloved by tourists, joggers and landscape painters, it is a challenging environment for wildlife because the soil (where there is any) is so thin. Rainwater drains off almost instantly, so the vegetation struggles to survive and there aren’t many herbivores to feed the carnivores. Nevertheless, on Sunday I spent almost an hour in a little patch of open scrub near the summit, watching to see what was around, and was well rewarded.
There were grasshoppers, butterflies (Blue Tigers, Migrants, Crows and a few others), a couple of bee-flies, a baby mantis and lots of ants (links here take you to these insects on my flickr photostream), but the spiders drew my attention. There were odd little patches of silk in a few seed-heads of the tall grass and I pulled one apart to find a small pale-gold spider, while a similar but bigger patch in a knee-high sandpaper fig tree was home to what looked like a whole family (a female guarding her egg-sac and a smaller adult which could have been the male) of grey-brown spiders. A slim grey spider with enormously long legs appeared on the trunk of a poplar gum and wandered off again, and I watched the later stages of a deadly attack on one spider by another.
The attacker was a jumping spider (Salticidae, perhaps a Sandalodes) and its prey was a Lynx (Oxyopes macilentus). Both are predators, but the Lynx is an ambush hunter, typically waiting for prey to come within reach, while jumping spiders are roving hunters. In this case it looks like the jumping spider, the larger of the two, had chanced across the Lynx and lived up to its name; the Lynx offered very little resistance to its larger attacker.
How big are they? Not very big at all: perhaps 11 mm and 7 mm. If I hadn’t chosen to sit quietly and look around, I wouldn’t even have noticed them in the grass.
We took advantage of the Boxing Day holiday to drive down to the camping and picnic area at Alligator Creek. It is normally a popular spot but the long dry spell which only ended on Christmas Eve seems to have discouraged the campers and even the day-tripper numbers were down, so it was pleasantly quiet. We paddled in the shallows, swam in the deeper pools, clambered over the rocks and enjoyed a picnic lunch. All of us are enthusiastic about wildlife and all of us had cameras so my photographic haul for the day is only about a quarter of the total.
We all took photos of the scrub turkeys, Alectura lathami. There were plenty of them around and they were absolutely comfortable with human society – even to the point of shopping at Supré, apparently:
They are large and somewhat clumsy birds but my third photo here is misleading: the bird did not crash-land at all but was enjoying an energetic dust-bath. A far more formal portrait is here, on my Flickr photostream.
The scrub turkeys were not the first creatures we noticed on arrival: the cicadas were. Their screaming drone is characteristic of the Australian bush in summer and dominated the picnic area. After a while we saw some of their cast-off shells (here and adjacent) clinging to tree-trunks and saplings but we never did see any of the adult insects; they must have been high in the trees.
I also brought home pictures of spiders – another ant-mimicking jumping spider, a tiny yellow spider which had somehow defeated a green-ant plus a couple of others – flies (1, 2), dragonflies, damselflies and a marvellously camouflaged mantis:
A post about an earlier visit to the same park shows the scenery and some more of the fauna, while this link will take you to a composite collection of my Flickr photos of the wildlife.
Even after a couple of years photographing bugs in my garden I come across insects which are quite new to me. I got another one just a couple of days ago, a mantis-fly:
The photo makes it look very much like a praying mantis but in real life you would notice that is is tiny compared to an ordinary green mantis like this. In fact, it is only 10-12mm long. A baby praying mantis could be this small but wouldn’t have wings – see this little brown one, for instance.
The mantis-fly does use the same hunting strategy as praying mantises – sit and wait, then grab with those over-developed front legs – but it is not closely related to them. Rather, it is a cousin of lacewings and ant-lions, a family within the order of Neuroptera. (Once again I will use an index page on Graeme’s Insects of Townsville site to illustrate the relationship.) There is a nice introduction to Neuroptera here, on the Queensland Museum website. There are 45 Australian species of Mantispidae and I’m not sure which one mine belongs to.