Wheel of life #2
Ronlit’s recent post Wheel of life on this blog described the mating habits of dragonflies. Our garden pond has been a magnet for a number of these attractive creatures, particularly Blue Skimmers (Orthetrum caledonicum) which are surprisingly approachable and obligingly performed the ‘wheel of life’ for the camera – see photo at left.
Another smaller dragonfly, the Black-faced Percher (Diplacodes melanopsis), was flying around at the same time, and was occasionally buzzed in mid-air by the male skimmer when it got too close.
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- Blue Skimmer on Triggerplant (Stylidium sp.)
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- Blue Skimmer with Blue Devil (Eryngium ovinum) in the background
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- Blue Skimmer clinging to a Flax-lily (Dianella sp.)
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- Black-faced Percher
We have much to learn about these insects and were grateful for Ron’s help with identification. We also referred back to his 2013 post When beliefs are shattered, which was a delightful story about the differences between dragonflies and damselflies, and which elicited a wonderfully detailed comment from the late Russell Best, co-founder of the NatureShare website.
Evolution at work?
The Australian Magpie is a well-known bird distributed across most of mainland Australia and Tasmania. It consists of one species Cracticus tibicen but has three recognised forms: the Black-backed Magpie (pictured left) of which there are four races, the White-backed Magpie (pictured below right) of which there are three races and the Western Magpie. Each race is distinguishable by different black and white patterning. The races easily hybridise, forming many intermediate patterns.
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In southern Victoria (including the King Parrot Creek Valley) the nominate race is the White-backed Magpie (Craticus tibicen tyrannica). However the avid twitchers among us and those who have run the gauntlet of swooping magpies when getting to their washing lines in Spring will also have observed Black-backed Magpies, even though their typical range is further north.
Driving along the King Parrot Creek last week I noticed this magpie (picture below), which doesn’t seem to fit any of the recognised colour forms. I am calling it the Whiter-than-white-backed Magpie (Craticus tibicen ronlitians). It is not an albino, as albinism is the total lack of colouration and this bird has dark eyes and 
patches of black. But it is much whiter than any magpie I have seen before.
Bearing in mind the theory of evolution and the survival of the fittest, and relating this to the dismal form of the Collingwood Football Club over recent years, maybe this magpie represents the next step in the slow evolution to a more successful bird … maybe a (white) Swan. Often seen on football ovals in Sydney of course.
Creek life
There was perhaps some degree of scepticism after the Strath Creek Landcare Group’s recent Platypus Group Watch on King Parrot Creek when one of the organisers was the sole person to spot a platypus, but had no photo to confirm it. Ron at least had the presence of mind to get a picture of the only rakali (Water Rat) seen during the evening. Then we got word that the Green Army team working on weed control in Coonans Reserve had spotted a platypus in the creek on their early morning arrival at the reserve.
So the other morning we went to see for ourselves and were immediately rewarded with a rakali paddling like mad downstream and disappearing under a fallen log. Then, a few minutes later, a platypus appeared in mid-stream and we were finally able to get a few (poor quality) photos.
The creek is still flowing (just) and there are still plenty of deepish pools for the aquatic life, but Waterwatch and the Catchment Management Authority are keeping a close eye on dissolved oxygen (DO) levels so as to be prepared for the possibility of intervention to save the endangered Macquarie Perch, should the need arise. Low flow and raised water temperature, combined with the decay of organic matter, can cause DO to fall to levels that result in stress and even death to fish.
Meanwhile …
… the Yea Wetlands is holding the inaugural Platypus/Rakali Group Watch on Wednesday 9th March. A BYO picnic and briefing begins at 5.30pm in the Cummins Lagoon car park. For full details of the event, click on the flyer.
Wheel of Life
At around this time last year we posted a blog featuring the mating practices of damselflies, one of the groups of insects in the order Odonata. Well those odonatans are at it again. This time it is the dragonflies that we have watched cruising above the dam.
Male dragonflies at this time of the year aggressively defend a territory, in this case a section of the dam. Any other male entering that airspace is swiftly driven away. Anything else entering the area is likely to be eaten. I was attempting to photograph a damselfly (species unknown), which is a poor flyer that usually flutters vertically into the air when disturbed. My camera shutter opened a split-second too late as a dragonfly grabbed the hapless damselfly, flew away and ate it. On the other hand, female dragonflies entering the zone are courted.
In preparation for mating the male places sperm packets in an easily accessible position on its body. A mating pair is established when the male grasps the female behind the head with claspers on the end of its abdomen. The pair then grab onto a branch or stem and form what is known as the wheel position (see picture above) where the female curls her abdomen underneath the male and picks up the sperm from under the thorax.
Still attached, the pair then fly above the water body so the female can deposit eggs on submerged vegetation (pictured right). During this time the male still has to defend the female from other male dragonflies which can, given the chance, scoop out the rival’s sperm packet and replace it with their own.
And so the wheel of life rolls on.
Stick your tongue out and say Ahh!
As a child I could never understand how a doctor could deduce anything from asking me to stick out my tongue and say ‘Ahh!’ – but they obviously could. Rosemary from Flowerdale recently sent in two photos on a related theme, of a moth feeding from flowers.
The mouthparts of butterflies and moths are primarily used for sucking – usually liquids like nectar or plant sap. The main organ, which I incorrectly equate to the human tongue, is 
called a proboscis from the Greek pro meaning forward and bosko meaning to feed. In butterflies and moths the proboscis is curled up under the head and extended when being used to suck liquids.
Other sucking insects such as aphids, cicadas and tree-hoppers (pictured below) also have a proboscis, which they use to suck liquids from either vegetation or other insects. Their
Gumtree Hopper nymph
proboscises are much shorter and more solid as they need to pierce as well as suck. Their proboscis therefore do not curl.
From the photos it is difficult to determine the species of moth, but there is no doubting it has a very long proboscis. If I had a tongue that long I could probably have my doctor examine it in Whittlesea while I was sitting at home in Flowerdale.
Turtle spotting
You may have seen our local turtle species, the Eastern Snake-necked Turtle (Chelodina longicollis) heading overland or perilously crossing the road, usually after heavy rain. But in the water it is far more cryptic, and often all you see is its snout and eyes protruding above the water-line (see photo above), until it sinks to resume feeding on a range of aquatic creatures. Its long neck allows it to strike like a snake at fast-moving prey.
We have counted up to seven turtles of various sizes in our dam at present, and have had reports of larger numbers in the past in dams around the district. And they are not restricted to dams – during the recent Platypus Watch conducted along the King Parrot Creek by the Strath Creek Landcare Group, one was spotted in the creek where it flows through Coonans Reserve.
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- Algae-covered dinner plate in King Parrot Creek
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- Not a dinner plate at all
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- Fully visible turtle in King Parrot Creek
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- Rising from the depths in our dam
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- Heading cross-country – past our doorstep!
The Eastern Snake-necked Turtle is one of a number of freshwater turtle species that were previously known popularly as tortoises, a name that is now reserved for land-based tortoises such as the Galapagos Tortoise. There are no native land-tortoises in Australia.
To learn all about the Eastern Snake-necked Turtle and other turtles, you are invited to attend a Focus on Fauna talk by Graham Stockfeld next Friday evening (19th February) starting at 7.30pm in the Strath Creek Hall. Click on the link to the flyer Talking about Turtles for full details, and we ask that you RSVP if you plan to come along.
In the meantime, why not spend a while beside a dam or creek – it’s quite likely a pair of nostrils and beady eyes will break the surface near you!
To Bee or not to bee?
In a recent photo competition run by the Upper Goulburn Landcare Network one of the most popular subjects was the Blue-banded Bee (Amegilla cingulate), pictured above. Speaking to the photographers it appeared that this was the first time that they had seen these striking insects in their respective localities. Indeed a blog on this very insect was posted recently for that exact reason.
Last week I noticed an insect digging in a bare sandy patch in the garden that that looked at a distance remarkably like the aforementioned bee. In fact up close it was a dead-ringer. The insect was a Sand Wasp (Bembix sp.), which also featured in a blog last year (pictured below).
Both insects display striking blue bands on their abdomens. The adults of both insects are nectar feeders. They have the ability to sting but are not easily annoyed. Both insects build tunnels underground in which to lay their eggs.
The difference? Well obviously one is a wasp and the other a bee. The Blue-banded Bee larvae are fed on nectar while larvae of the Sand Wasp feed on paralysed spiders. Adult Sand Wasp jaws are much larger so that they can carry those spiders off to the tunnel, and their thorax is not as hairy as that of the bees.
None of this really matters…unless you are a spider. It is hard to get close enough to either insect to notice the physical differences. We should just celebrate the diversity – even if we can’t at first glance tell them apart.
It’s a strange old world
Spring and summer are the mating times for many Lepidoptera – butterflies and moths. Their spiralling and sometimes frenzied courtship flights are precursors to eggs being laid on the favourite food plants of the future caterpillar. Currently in egg-laying mode is the Australian Grapevine Moth (Phalaenoides glycinae), pictured left.
The Grapevine Moth is a mainly black and cream day-flying moth endemic to south-eastern Australia. The adult moths have handsome bright orange tufts of hair on their legs and abdomen (below right). The caterpillars feed on native plants such as Hibbertias and Paperbark Mistletoe.
When grapevines were introduced to Australia it was found that the Grapevine Moths were partial to this plant — hence their name. They lay eggs on the underside of new vine leaves and the caterpillars feed on these and the developing fruit. The picture below left shows a moth in the process of laying an egg (click photo to enlarge).
And so it is that the native Australian Grapevine Moth is now regarded as a pest in its own land (and other countries) for feeding on an introduced plant. To make things even more strange, one of the methods of trying to control this moth and other insect pests was the 
introduction in 1862 of the Indian Myna (Acridotheres tristis) — a strategy that did little to control the Grapevine Moth and created an even bigger nuisance, the bird itself.
It’s a strange old world we live in.
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P.S. Coincidentally, Dave Hubbard just sent in this photo (below) of the same insect. They are obviously making an impression at the moment.
A host of herons
White-faced Heron on a Flowerdale roadside
Often solitary, the heron is reported to form companies in autumn, but autumn is still away off, and 14 seems quite a large flock – maybe something to do with El Niňo weather patterns perhaps?
The White-faced Heron has also been known as Blue Crane, a misnomer since the cranes (Brolga and Sarus Crane) belong to a separate family, despite their superficial similarity. It is found throughout Australia as well as Indonesia, PNG, New Zealand and nearby Pacific islands.
Janet sent us the central photo above which shows one surprise sighting in her daughter’s backyard pond in suburban Montrose! Click for a closer look.
White-faced Heron calls:
Aliens IV: Infestation
Those who are fans of sci-fi will know that when aliens invade earth they multiply in egg-shaped sacs hidden somewhere safe like in an underground cave or cellar. Those sacs may or may not contain a human host on which the developing alien might feed.
The photo above taken recently could be of a terror (the new collective noun for aliens) of extraterrestrials or it could simply be a group of Hemipterans (true bugs) hatching on a Poa sp. seed head. Hemiptera is an order of insects that includes cicadas, leafhoppers and aphids, which are distinguished by common sucking mouthparts. All insects in this order either suck on the sap of plants (below right) or on other insects (below left).
Gumtree Bug instar sucking sap
Hemipterans do not undergo a complete metamorphosis, changing from a caterpillar to an adult, as moths and butterflies do. Instead they are born looking similar to the adult and progress to that state through a series of ‘moultings’. This is known as hemimetabolism or partial metamorphosis.
Pictured (top) is a species of Stink Bug. The newly hatched young (known as instars) look very similar to the adult but lack the wings. There are five stages of ‘moulting’ before the adult emerges. The 1st instars do not move far from the egg shells. Their food source is the bacteria left on the egg shell by the female adult when the eggs were laid. After the first moulting, the young (2nd instar) will wander off to look for food.
Assassin Bug sucking on a beetle
Both the instars and adult stink bugs (more politely known as Shield Bugs) will excrete a foul-smelling liquid when disturbed. This liquid deters predators such as wasps which paralyse the bug and use it as a host for its larvae.
I reckon this has the makings of an Alien movie blockbuster. I just need to work out who plays Ripley.
