A good guy with a bad name
Sometimes your name can give people the wrong impression. For example, as soon as people find out that a rakali is an Australian native water-rat, the term rat just puts them off. And a rakali is one of the cutest critters going. Similarly for cockroaches. They are automatically associated with spreading germs and disease. However there are a lot of native cockroaches out there who do not deserve that reputation.
The cockroach pictured below is a native Austral Ellipsidion Cockroach (Ellipsidion australe).
It is a daytime active insect. Unlike many other cockroaches it is not a scavenger but feeds on pollen, honeydew and mould so is a good guy around your garden and one of the native pollinators.
Beware the assumptions in a name.
Dressed to impress
At some point in our lives we have all dressed to impress a potential partner. Combed the hair (a dim, distant memory for me!), polished the shoes, put on sharp threads. Surprisingly some birds do the same thing (not the shoes though).
The bird pictured left is an Eastern Great Egret (Ardea modesta) –formerly Ardea alba, hunting for dinner. It is the tallest of the Australian egrets with a head and neck being almost 50% longer than the body. Note the smooth feathers and the yellow bill. This bird, photographed last year, is in non-breeding mode, just mooching around minding its own business.
This time of the year is the breeding season for egrets and herons and some go all out to attract a mate. The picture below, taken this week, is of an Eastern Great Egret (not the exact same bird) in ‘dressed-to-impress’ breeding attire. During breeding season the bill turns black, the facial skin turns green and the bird displays erectile plumage that drapes over the back. If I were a potential partner I’d be impressed.
Compare this to the breeding display of a Nankeen Night Heron (Nycticorax caledonicus) photographed last week on the banks of the Yarra River in Melbourne. It consists of one to three white plumes extending from the back of the head.
Sometimes less is more.
Spot the Rakali
Spot the Rakali
The SCLG event has been held annually for at least 10 years now. This year no platypus were sighted, which was disappointing but doesn’t necessarily mean there were no platypus in the section of creek surveyed. However, observers at four of the five sites were lucky enough to spot a rakali. Given the timings of sightings and the distance between sites, it is likely there were at least three, and probably four, individual animals.
The best sighting was by Janet and Terry who had a rakali that perched on a log in the creek (click on photo above), then swam around in front of them for 5 minutes.
Carp
Electro-fishing
Macquarie Perch
The healthy state of fish stocks in the creek was shown last week during an electro-fishing demonstration at Moores Road Reserve, following a meeting of Goulburn Broken Catchment Management Authority staff and local Landcare group representatives with Karen Lau, the newly appointed Executive Director of Catchments and Waterways at DELWP. In a fairly short time, in only about 100m of creek, ARI scientists had collected a bucket-full of temporarily stunned fish, including many Blackfish, both River and Two-spined, trout, a Freshwater Cray and two endangered Macquarie Perch. As a rule of thumb, electro-fishing captures about 20% of the fish in a given length of stream, so in this section of the King Parrot, there were clearly a lot of fish indeed!
Well I never
It is not every day that I see an insect that I am at a total loss to identify, even at an Order level, i.e. beetle, butterfly, wasp, etc. Usually I can guess what it is by looking at the physical characteristics and because I have seen it, or something similar, before or have seen a picture of it.
Take the Rove Beetle for example (pictured left). Even though looking at it one would be hard pressed to identify it as a beetle I had seen pictures of it before so the identification was not that difficult.
This week a night insect (see picture right and below) flew into the lounge and landed on a lamp shade. It had a long tapered body consisting primarily of abdomen which it waved around energetically and wings which only extended part way down the body. It also had short antennae and fly-like eyes – sort of lacewing, sort of owlfly, but not quite. My usual ‘go-to’ websites of insects photos like http://www.brisbaneinsects.com and http://www.lifeunseen.com did not come to my rescue this time. I’ve never been in this situation before. So my blogger colleague Macwake posted the picture on www.bowerbird.org.au and asked the question. And sure enough someone (Simon Ong) identified the critter as a beetle of the family Lymexylidae of the genus Atractocerus.
Larvae of this genus are wood-boring. The eggs are deposited in the crevices of bark by means of a long ovipositor and the larvae when hatched bore straight into the wood. The wood shavings are used to block the tunnel from predators or parasites.
To say the insect is boring is factually correct but the hunt for its identity was not.
Soundz of Summer
Almost everyone has a sound that they associate with summer. For some it is the call of the cicadas at dusk. For others it may be the tick-tick of the garden sprinkler. For me it is the muscular buzz of the robber fly hurtling past looking to catch its prey on the wing. Robber flies are the terminators of the insect world and though I hear them I rarely see them flying such is their speed.
Recently I heard a buzz almost as powerful. The source was easily seen and luckily landed on a nearby bush. It was a pair of mating March Flies –in this case Yellow Tangle-vein Flies (Trichophthalma sp.), I think.
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Both male and female flies feed on nectar and plant juices. However when the female fly is producing eggs it requires protein which it gets by extracting the blood from warm-blooded animals particularly livestock, domestic pets and humans. The mouth parts are equipped with two knife-like appendages with which to pierce the skin and a sponge to soak up the blood. The sponge can clearly be seen in the photo above. Although the bites may trigger allergic reactions in some people, most only feel a short pain followed by itchiness which is due to the anticoagulant the fly injects to ensure a continuous flow of blood.
This pair sat mating until the camera got too close after which they took off still connected. Because of the difference in wing strength between the two flies they flew off spinning quite rapidly. Mating in the air can be a dizzying experience (I’ve been told).
Quite a mouthful !
As is their custom, our resident Grey Shrike-thrushes have again nested in the corner of our shed, and their three eggs have successfully hatched. The parents have been warily landing in a tree just outside the shed before going inside, and it is interesting to see the wide range of prey they are carrying to the hatchlings: a great variety of insects, spiders and even small reptiles, like the skink pictured above, probably the common Garden Skink.
What’s surprising to us is that the skink was taken straight to the nest when the chicks were, we think, only a couple of days old, still blind and largely bald – see picture at right. This particular visit by the parent seemed short – not long enough for it to tear the skink into manageable bits, so presumably the young chicks were somehow able to handle the meal themselves!
A few days later, and a noise made by us in the shed was often enough to trigger the gape response in the hungry chicks expecting a parental visit, as seen in the photo below, which clearly shows their yellow/orange gapes.
No Heinz baby food for these youngsters!
The Bristly and the Beautiful
Flies in Australia get a bad rap. I grew up in the era of the antihero, Louis the Fly, who came ‘straight from rubbish tip to you’. And I cannot count the number of times that flies have made an outdoor summer event less than ideal. However there are flies and then there are flies.
Rutilia sp.
Bristle Fly (Amphibolia vidua)
Last month Macwake published a blog on the Golden Headed Rutilia Fly (Rutilia argentifera). This fly is of a group known as Tachinid Flies. With the advent of summer a number of tachinids have been seen in the district. On first sight they look like any other fly but are distinctly bristly, hence the name Bristle Flies. Tachinids are generally larger than the common house fly and in the case of those photographed, much larger. The adults feed on nectar and the honeydew excretions from insects such as aphids and scale insects (not a rubbish tip in sight!). As Macwake noted, flies like these are important players in the pollination of plants.
Microtropesia sinuata
***WARNING – GRUESOMENESS AHEAD*** Most tachinid flies deposit eggs on a live host, usually the larvae of butterflies and moths. After a few days the eggs hatch and the maggots bury themselves into the host and proceed to eat it from the inside, eventually killing the host. For flies of the Rutilia genus, the eggs are laid on the ground and the hatched maggots dig into the ground looking for the larvae of Scarab Beetles which they parasitise. These flies are important controllers of pests and some species have been used as biocontrols.
Rutilia sp.
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A close examination of photos shows these flies to be both bristly and beautiful – just like (dare I say it) my partner’s legs…this may be my last blog!
Who needs trees?
Peron’s Tree Frog
At least we think it’s Plains Brown Tree Frog – a species that is difficult to distinguish from the closely related Southern Brown Tree Frog, Litoria ewingii. The skin markings are variable in both and the main differentiation is in the call and the distribution, although the Plains is reported to be slightly smaller. We have been told that we are in an overlapping zone of the two species, and if the frogs aren’t calling, it makes identification difficult.
We hear frogs all the time, but it’s not often we are able to get up close enough for clear photos. This hideout of the frogs between pipes was an ideal opportunity to show some of their identifying features, such as the tympanum (ear), the foot-webbing and digit pads, the eye pupil etc. The Peron’s Tree Frog, for instance, is immediately recognisable by its cross-shaped pupil, if not from its weird call. Now, if only the other little frog had a name-tag!
Listen to the calls previously recorded locally by clicking on the sound bars below:
Peron’s Tree Frog –
Plains Brown Tree Frog –
Insect onesies
Unlike humans, insects have external skeletons (exoskeletons). One of the advantages this offers is that internal organs are well protected from injury and damage. However the downside is that for those insects that do not go through a caterpillar/cocoon stage, that is, they mature as a series of nymphs (or instars), they periodically need to moult their external skeleton and grow a bigger one. These insects include true bugs (hemiptera), grasshoppers, dragonflies and cockroaches (see photos).
Cicada
Native Cockroach
Spring and summer are when most insects hatch and grow. It is common at this time of the year to see the discarded insect skeletons hanging around, like abandoned onesies. The process of shedding the skin is called ecdysis. Seeing ecdysis in action though is not so common. One needs to look carefully through the vegetation.
During ecdysis the emerging insect does not breathe. During this time it is most vulnerable to attack as it is pale in colour (i.e. not camouflaged) and the exoskeleton is soft. After shedding the old shell, the insect pumps itself up to maximum size using air and bodily fluids whilst the new shell hardens, after which it relaxes giving itself room to grow. The shell develops its colours on exposure to sunlight.
When you see the insect next to its discarded onesie you can only wonder how it fitted in the shell in the first place. It’s strange because my West Coast Eagles onesie looks too big whether I am wearing it or not.
One lump is all you need
As an amateur photographer I rely on seeing things to take a picture. Recently I have participated in a number of bird surveys where the expert twitchers marked down that a bird had been ‘sighted’ when they have heard its call. This initially astounded me but of course it makes sense that if bird calls are unique to a species then hearing the call is just as valid as seeing the bird…and far more productive. It has opened up a whole new dimension as to how I ‘view’ nature.
Last week I HEARD a bird call I did not recognise emanating from the top of an old pine tree. In the uppermost branches sat a bird which was hard to photograph because of the bright sky background and the fact the camera kept focussing on the multitude of branches between me and the bird. What I did notice in profile however was the lump on its beak and that was all I needed to identify it (see picture above). In this part of the country it could only be a Noisy Friarbird (Philemon corniculatus). Australia has several species of friarbirds with bill knobs but the others are restricted to northern Australia.
Friarbirds are species of honeyeaters so called because their heads are bald, similar to the friars of old, and in large groups create a lot of noise with their constant chatter. Their alternative name is Leatherhead. In spring/summer they migrate down the east coast to breed in southern Australia. They feed on insects, fruit and nectar.
Even though the call was quite distinctive I don’t think I would recognise it again. I think I’ll stick to visual identification. Seeing is believing.
Focus On Fauna 