After the rain

pink and white bottlebrush flowers on tree
Bottlebrush flowers on the tree after the rain

We had our first cyclone of the season last week but it was only a little one (Dylan, category 2 at its biggest) and Townsville  was on the northern edge of its path so its main effect on us in Mundingburra was about 60mm of very welcome rain over two days. (Some suburbs did suffer more, I know, particularly from the storm surge on the Thursday morning. I don’t mean to be dismissive of their losses but I’m writing about my own little part of the city.)

The plants responded enthusiastically to the rain, none more so than the pink and white bottlebrush (Callistemon; I think it’s  a hybrid cultivar) in front of the house.  The insects, in turn, responded enthusiastically to the flowering plants and I have had fun seeing just how many different kinds I could spot on this one tree:

brown and white beetle on flower
Brown Flower Beetle, Glycyphana stolata, a scarab
black and yellow wasp on flower
A flower wasp, Campsomeris radula
Large mosquito on bottlebrush foliage
Metallic Mosquito, Toxorhynchites speciosus

The Metallic Mosquito is a very large species but does not, thankfully, attack humans. In fact it makes itself useful to us by preying on other mosquitoes. (One expert in Thailand counted some 420 species of mosquito of which a mere couple of dozen ever fed on people. Mosquitoes are victims of their bad press just as much as spiders are.)

Green bee amongst the stamens
A small native bee, Colletidae family

There were perhaps a dozen of these bees around the tree at any one time, making them the most numerous of the insects enjoying the flowers (which included, incidentally, some tiny black beetles which were too small and dull to photograph successfully).

Taking advantage of all of them, or trying to, were some predatory spiders – Lynxes – lying in wait amongst the flowers. I saw two different species. Both these spiders are very small, about the size of a house fly.

orange-brown spider on leaf
Lynx spider (Oxyopes genus) on bottlebrush leaf. It has a grey abdomen
brown spider with spiky legs
Lynx amongst the stamens

Townsville Beekeepers Association at Eco-fiesta

beekeepers flyer

More from the Eco-fiesta, as promised: the Beekeepers were handing out flyers for their own activities (download the pdf here for contact info) and a warning about the Asian honey bees from Biosecurity Qld which you can get here. They were also showing off hives and sharing honey … which you can’t get here, unfortunately.

I didn’t see any information about native honey bees at the stall but it’s quite possible some of their members do keep them.

Abundant invertebrates

black butterfly attacking a black and white one on a pink-flowering creeper
A Common Crow, Euploea core, attacking a Marsh Tiger, Danaus affinis, feeding on Maiden’s Blush creeper

A week ago I mentioned my surprise and disappointment at how few bugs I found in a Hobart garden in the week after Easter. One of the expert Tasmanian bug-hunters I mentioned in that post was amused by my reaction:

I had a good laugh at your disappointment … Unfortunately you did come down at the beginning of the ‘slow’ period (especially bad April to August). We do have winter insects but for the most part it’s more a specialist pursuit of the very small critters :-)

In retrospect, I think there were two reasons that the low numbers surprised me. One is that my memories of childhood in South Gippsland (the nearest thing to a Tasmanian climate I have experienced) have probably been skewed by the fact we didn’t spend much time outdoors in winter, as well as blurred by the decades in between. The other is that I hadn’t really thought about the difference between Tasmania’s seasonal variation and Townsville’s. We have comparatively little variation in day length or temperatures and our far greater variation in rainfall seems not to matter quite so much. (N.B. the temperature scales on these two charts are the same but the rainfall scales are not.)

Hobart monthly temp and rainfall Townsville monthly temp and rainfall chart

A stop on the way home from Reef HQ Aquarium on Thursday drove home the difference quite emphatically, although quite by accident. I pulled up beside a mangrove creek which runs through a narrow strip of parkland between South Townsville and Hermit Park (something I have done several times before – see this post and links from it) and in the space of half an hour or so I was able to photograph, not just observe, more species of butterflies and more species of true bugs (Hemiptera) and more species of spiders than I had seen in my entire week in that South Hobart garden. I also saw, but didn’t photograph, another species of butterfly, some small grass moths, two species of native bee and various flies.

The links on this list mostly lead you to older photos, here on Green Path or on my Flickr photostream, but a couple taken on the day deserve more attention. One, showing the kind of behaviour that makes the observer rethink butterflies’ sweetness-and-light reputation, is featured at the top of this page.

orange-black bugs on twig
Assassin bug nymphs

Assassin bugs (Reduviidae) are common enough but this was the first time I had seen new hatchlings (here is a bigger one in the same parkland). They were dispersing down the mangrove twig away from the cluster of eggs they had just emerged from.

 

 

 

Bee heaven

Regular readers will know that from time to time I visit a family property on Hervey’s Range, in the hills about 40 minutes out of town. One of its outbuildings is a mud-brick pump-shed about two metres square with a corrugated iron roof. A big, old, rarely used pump takes up half the space on the dirt floor. [Update: photos of shed and the bushland around it added to flickr 1 Sept 2013].

Walking into the shed is like walking into a bee-hive. There’s a constant droning hum and constant movement of flying insects. The walls are pocked with dozens, hundreds, of holes which look like bullet holes but are in fact bees’ nests. The insects are not at all aggressive so one can stand there watching the activity and gradually make sense of it all – and take lots of photos, too, as I did last weekend (for the record, nearly 100 photos in just over half an hour) . Many of the best are on my Flickr photostream but I’ve put one of each species here too, to see if I can make the connections between the different creatures living together. (Clicking on a picture will take you to a bigger version as usual, but this time it will be on Flickr and there will be another picture of the same species adjacent.)

Three bees:

Blue-banded Bee 6440

Blue-banded Bee, Amegilla sp., Apidae. By far the most numerous species in the pump-shed, and makers of the nesting holes. Most sources only mention Amegilla cingulata but Graeme Cocks notes that “there could be four species locally.”

After mating, female blue banded bees build a nest hole into soft sandstone or clay. Cells at the end contain an egg and food (pollen and nectar) for the larvae when it emerges. A single hole can actually be a complicated maze of tunnels. Although solitary, many blue banded bees may build their nest burrows in the same spot, close to one another, but it is not a colony [in the way a honey-bee hive is a colony]. … The eggs in each nest develop but remain sealed in their cells until the warm weather returns and they emerge as the next generation of adults. (Source: bluebandedbees.com)

Fire-tailed Resin Bee 6368

Fire-tailed Resin Bee, Megachile mystaceana. About the same size as the Blue-banded Bee but there were only three or four around at any one time.

This Resin Bee female builds nest in existing cavity … (Source: Brisbane Insects)

Fire-Tailed Resin Bee (Megachile mystaceana) … is a great looking bee with a bright orange abdomen. … These bees will create a series of individual compartments (between about 8 and 12) within each hole and provision each compartment with pollen and nectar before sealing the end of the hole with a mix of resin and mud. (Source: nativebees.com)

Neon Cuckoo Bee 6359

Neon Cuckoo Bee, Thyreus nitidulus, Melectini, Apinae, Apidae. Much brighter than the Blue-banded Bee but a little smaller and far less numerous, with only one or two cruising around the shed. (A better photo is here.)

The female neon cuckoo bee seeks out the burrow nests of the blue-banded bee (Amegilla cingulata), and lays an egg into a partly completed brood cell while it is unguarded. The larval cuckoo bee then consumes the larder and later emerges from the cell. (Source: wikipedia)

The wasps:

Cuckoo wasp 2 6432

Cuckoo Wasp. A beautiful metallic green wasp, much smaller than any of the bees at only 6-8mm long (i.e. not the more familiar bee-sized Cuckoo Wasp, Stilbum cyanurum, here although colours are very similar).

[Cuckoo wasps] are most diverse in desert regions of the world, as they are typically associated with solitary bee and wasp species, which are also most diverse in such areas. (Source: wikipedia)

On finding the eggs or the nest containing eggs of a suitable species, such as the Mud-dauber Wasp, the female cuckoo wasp lays an egg next to the egg of the host species. The cuckoo wasp’s egg hatches first and the larva eats the food that is stored for the Mud-dauber’s young. … (Source: Australian Museum)

Wasp Gasteruptidae 6378

Gasteruptiid wasp. A very slim wasp with a body length about 22mm, an ovipositor almost as long again, and long dangling hind legs. I only saw one of these, flying in from outside and hovering along the face of the wall looking for something or other.

Gasteruptiid females oviposit in the nests of solitary bees (Apidae) and wasps (Vespidae) , where the larvae are predator-inquilines, eating the host egg or larvae and consuming the pollen store. Adult gasteruptiids may be seen on flowers or hovering near bare ground, logs or trees. (Source: CSIRO)

Cuckoo wasp 1 6405

Velvet Ant, Mutillidae (not a Cuckoo Wasp as I first thought). A beautiful, hairy, metallic blue-green wasp about the size of the Cuckoo Wasp at 6-8mm long. Male Velvet Ants, like this one, are winged; females are wingless (see CSIRO’s What Bug is That for more information).

Ant or wasp? Mutillidae? 6399

Velvet Ant, Mutillidae, female. I saw this one scurrying around on the shed wall and couldn’t decide for a while whether it was an ant or a wasp.

Mutillids are ectoparasitoids, and can be found on bare ground, sandy areas, tree trunks and walls where they search for nests of Sphecidae, Crabrionidae, Vespidae and Apidae whose larvae or pupae they parasitise. (Source: CSIRO)

Wasp nest entry 6425

I don’t know the maker of this nest but I do know that it isn’t any of those above. A wasp (Eumeninae) has converted a bee’s nest to her own use by plugging the original entrance and fitting a narrow spout-like entry.

Other small wildlife:

Fly uid 6415

Fly. This one species of fly was quite numerous. They spent most of their time resting on the shed wall, and they looked as though they were observing the bees and looking for chances to raid nests.

Their size and conformation reminds me of Tachinidae and the  Australasian/Oceanian Diptera Catalog notes that “The majority parasitize either larvae of Lepidoptera or larvae or adults of Coleoptera, but others attack adults of Hemiptera (Heteroptera), larvae of Hymenoptera (sawflies and social Vespoidea), or adults of various orthopteroid orders.” This is all quite speculative, however, since I’m not sure that my flies are Tachinidae, nor that Tachinidae do parasitise any of the bees nesting here.

Spiders. One abandoned huntsman exoskeleton (I can hardly call it a ‘shed skin’, can I?) and lots of small webs but not a great population of live spiders.

Ant-lion nymphs, in their volcano-shaped pits on the floor.

Why are they all there together?

In case you didn’t put the pieces of the puzzle together as you went along …

  • The Blue-banded Bees are there simply because it was a great  place to make nests.
  • The Fire-tailed Resin Bees are there because they like to re-use the Blue-banded Bees’ empty nest-holes.
  • The Neon Cuckoo Bee is there in the hope it can drop an egg into the new nest of a Blue-banded Bee.
  • The Cuckoo Wasp, Gasteruptiid wasp and Velvet Ants are there for much the same reason, although they may be parasitising the Fire-tailed Bees and/or the unknown maker of the nest with a spout entrance (the Gasteruptiid seems very interested in it here) as well as, or instead of, the Blue-banded Bees. Note that they can’t be planning to parasitise each other’s nests because none of them make their own nests.
  • The flies may be there for the same reason, or maybe they just like to steal food from the bees.
  • The spiders and ants just like a cool shady place to lie in wait for prey.

What a bee-hive!

Update 20.1.13: corrected identification of one photo, male Velvet Ant not Cuckoo Wasp.

What’s around – mid December 2012

cicada on wall
Yellow Tree Buzzer, Pauropsalta eryei

July’s rainfall total was 106mm, all of which fell between the 10th and 16th. Since then, i.e. in the last five months, we have had a total of only 10mm, the last of which was 0.4mm on Nov 18. Dry season indeed!

That said, temperatures and humidity have continued to creep up over the last month, and plants and animals alike have begun to anticipate the coming Wet. Our lawn has started growing again, the poincianas are flowering, the ball-of-fire lilies have flowered and the Carpentaria lilies have sent up stalks and leaves.

Probably the most notable change in our insect world is that Christmas beetles have arrived (mid-size brown and green ones, anyway; I haven’t seen the big golden ones yet, or an elephant beetle).

brown butterfly with white markings
Blue-banded Eggfly, Hypolimnas alimena, on banana trunk.

The first cicadas are here, too, and tiny grasshopper nymphs. Mud-dauber wasp numbers have increased, with Delta, Sceliphron and an unidentified red and yellow species of Eumeninae all building their nests.  The paper wasp nest I showed in September is still occupied but has hardly grown, as there are still only a couple of adult wasps at it. Blue-banded and Resin bees are around, too – one of the former met a sticky end at the hands (proboscis?) of this robber fly.

There have still been no mozzies to speak of. That is not a disappointment.

The hang-on-through-the-dry-season fauna is still hanging on: Lynx and Jumping spiders (but hardly any others), Green ants and Rattle ants, Leaf Hoppers (Flatidae) and a few other sap-sucking hemiptera; and Tiger craneflies,  Dolichopodidae, Soldier flies and hoverflies.

Ant-lion on frond
Ant-lion on ponytail palm

Of the butterflies, we are seeing Yellow Migrants, Pale Triangles, Junonia, Blue-banded Eggfly (a picture showing the blue bands is here), Common Eggfly, Cairns Birdwing, Zebra Blue and Magpie moths, but all in small numbers.

There are always ‘strays’ – critters which are new to me (still!) or which I know but rarely see. A tiny, gangly wasp in the former category is here, and the ant-lion at left is in the latter.

This time last month and last year.