What’s around – mid July 2012

 

Hover-fly on cream flower
Hover-fly (Syrphidae) on a Rosella flower, with ants on foliage if you look for them hard enough

We seem to be just easing out of a period of unseasonably cool, damp weather as I write and the invertebrates haven’t liked it any more than our tourists. It’s supposed to be dry and sunny here at this time of year, for goodness’ sake! We still have a reasonable variety of insects and spiders but numbers of each species are low and their activity is also low: they are cold-blooded (cold-ichored??) and, like reptiles, lethargic in cooler weather.

That said, we do have …

  • Butterflies: Junonia hedonia and Eurema, as usual; occasional Hesperidae, Migrants and Evening Browns; and not much else.
  • Moths: The usual grass moths; one or two others incuding Geometridae attracted to house lights at night.
  • Flies (Diptera): little green Dolichopodidae and hairy bluebottles as always, a few Hover-flies and Stilt-flies.
  • Mosquitoes (also Diptera): just enough to be annoying. We have had a few cases of Dengue Fever in Townsville recently, courtesy of the unseasonably wet weather permitting mozzies to breed and spread it from person to person.
  • Spiders: jumping spiders are still around but the small orb-weavers (Silver orb-weaver, Jewel spiders and St Andrew’s Cross spiders) predominate.
  • Ants (Hymenoptera): tiny ones when you look for them.
  • Wasps and bees (also Hymenoptera), ‘true bugs’ (Hemiptera), and dragonflies (Odonata): very few indeed. Mantises: even fewer.

A month ago and a year ago

What’s around – mid October

Still no rain* – at all** – and any area which doesn’t get watered by people is tinder dry or has already gone up in flames. People in one of our outer southern suburbs were under evacuation warning earlier this week but fortunately the threat was averted. We had a couple of days in the mid-thirties a couple of weeks ago, and then temperatures dropped again for a while but they are back up now and many of us suspect they are going to stay up – meaning daily highs of 32 – 36C and overnight lows around 20C. Humidity is up a little, too.

Hervey's Range Road
Hervey's Range Road, near the foot of the range: the undergrowth has been burnt out leaving the trees almost unharmed, and the grass will regrow with the first rain.

With all that, we are seeing a wider variety of insect life in the garden but not much increase in absolute numbers. Amongst the butterflies, Lemon Migrants, Ulysses, Orchard Swallowtail, Clearwing Swallowtail and Pale Triangle have joined Cairns Birdwings as frequent visitors, and all our recent residents – Chocolate Soldier, Crow and Eggfly – are still around (although still mostly male Eggfly; I have only seen one female). There are still Magpie Moths and the little grass moths, and a few more Hesperidae than we have been seeing.

Striped ichneumonid wasp
Ichneumonid wasp 1
White-tailed ichneumonid wasp
Ichneumonid wasp 2

Of the wasps and bees, the success stories are ichneumonid wasps, colourful mid-size to small critters with unpleasant baby-feeding habits, and my Blue-bum Bee, Amegilla. Of the flies, hover-flies still rule but there are lots of others as well; and I saw a Crane-fly pogo-ing around laying eggs in the soft dirt recently. Dragonflies have been returning intermittently and we have seen some of the smaller grasshopper species, a mating pair of giant grasshoppers, some ladybirds and a few shield bugs and pod-sucking bugs. Also, I’m less happy to report, a noticeable build-up of mozzie numbers. Oh well, the wonderful winter makes up for the less-wonderful summer.

I’ve been tracking spider numbers after a conversation with a southerner about the best time for a collecting trip up here in relation to our Wet/Dry seasons, and it’s looking tricky: we have had hardly any of the orb-weavers for a couple of months now but in the last few weeks I have been seeing lots of little ambush predators – Lynx and Flower Spiders (1, 2)in particular.

* What does ‘no rain’ look like on the map?

  • Qld July 1 – Sept 30 shows Townsville having had less than 25 mm in three months. (Compare it to the Jan 1 – March 31 map and you really see the Wet and the Dry.)
  • Qld September is even more impressive: Townsville is just on the edge of the white 0 – 1 mm area.

** Until after I finished writing the above. Let history record that on the evening of October 14, we had our first rain in six weeks and a pretty good thunderstorm. But I’m not going to rewrite my blog post!!

What’s around – mid September

Shield Bug on trunk of paperbark tree
Shield Bug on trunk of paperbark tree - quite well camouflaged, but he won't get any sap out of it!

Still no rain to speak of, in spite of indications to the contrary, so there is little change in the insect life except a continued dwindling of numbers. The garden is presently dominated by wasps and flies – hover-flies are doing particularly well, and we have more orange-and-black Plecia flies than I have ever seen before – while spiders are almost absent; there are no Silver Orb-weavers or St Andrew’s Cross spiders and even the spiky Austracantha have almost vanished.

Looking for butterflies I see (still) plenty of Junonia hedonia, quite a few Crows, Evening Browns and Dingy Bush Browns but (still) no Eurema. There are increasing numbers of Eggfly, both Common and Blue-banded but (curiously) all male. There are one or two male Cairns Birdwings around, too, but no females. I wonder why? My best guess is that gender balance is somehow controlled by humidity, so that there are not too many caterpillars until there is ample food for them.

What else do we have? A few sap-sucking Shield Bugs, like the one above but smarter; the occasional Ladybird and Giant Grasshopper; just one dragonfly and one praying mantis in the last couple of weeks; and quite a few tiny moths, although the only moth big enough to notice is the Magpie Moth. And so it goes … I think we’ll need some good rain before we see more activity. Latest predictions are that we’ll get quite a lot from La Nina, though not as much as we had last year.

One morning on Mount Stuart

View over Town Common, 16 km away, to Palm Island, 70 km away
View from Mt Stuart over Town Common, 16 km away, to Palm Island, 70 km away

Townsville winters are lovely. The weather has been so beautifully clear recently that I figured it would be worth getting up early just to take photos from the top of Mt Stuart of the sun rising over the ocean. Then, I thought, if I take food and coffee with me, I can wander round the mountain-top taking pictures of insects and trees and so on.

And so it was. I was on the road very soon after 6 a.m. and at the lookout on the mountain almost in time for sunrise. Continue reading “One morning on Mount Stuart”

What’s around in mid-May

Here we are, six weeks into the dry season: sunny days with a top of 25C or thereabouts after a chilly 10C or cool 16-18C overnight and no rain to speak of. (We have been watering our garden for a month. It felt so weird at first, so soon after months of flooding rain!) As you would expect, the wildlife has changed: no dragonflies, as I said, but what do we see?

    Butterflies: lots of Junonia hedonia, quite a lot of Eurema and Hesperidae, and a few each of Cairns Birdwing, Common Crow, Common Eggfly, Lemon Migrant, Ulysses, Orchard Swallowtail, Clearwing Swallowtail … that’s quite a long list, but in a walk once around the garden you would probably see ten Junonia, two Eurema and one out of all the rest.
    Moths: Hawk moths, usually in the evening and occasionally coming to indoor lights, and a lot of smaller moths flitting around the grass during the day and likewise coming indoors at night. Here’s one of last night’s visitors:
Can I call it a copper moth until I find out the real name?
    Wasps: paper wasps, hatchet wasps, mud-daubers (not many), and miscellaneous smaller wasps including Braconid and Ichneumonid species.
    Bees: hardly any, but occasional leaf-cutters and resin bees.
    Flies: yes, mostly the tiny green long-legged Dolichopodidae, plus a fair few hoverflies, bluebottles and crane flies.  There are more kinds of flies than most people suspect and I’ll have to put up some pictures soon.
    ‘True bugs’ (Hemiptera): occasional Hibiscus Harlequin bugs and a few others, but not many altogether.

    Grasshoppers: a few Giant Grasshoppers, mainly immature.

    Spiders: quite a lot of small ones – Austracantha, Silver Orb Weaver, St Andrew’s Cross, etc – but nothing much bigger than my little finger nail.

    Cockroaches and termites: lots in the compost bin and underground respectively, as always.

    Beetles, Mantises, Lacewings, Ant-lions: very few.

… which doesn’t mean there is nothing happening, but the garden is far less active than it was – reminding us once more just how much all life depends on water.