Go Tiges
Well the footy season is over for Richmond AGAIN! But rest assured all you Richmond Tigers fans, there are some Tigers—Water Tigers, that is—fighting and scrapping in your local dams and billabongs. Water Tigers (Dytiscidae sp., from the Greek dytikos meaning ‘able to dive’), pictured left, are the larvae of Predaceous Diving Beetles.
Both the adult beetles and larvae eat by grasping their prey between strong pincers. The pincers are hollow, which allows the Water Tiger to inject enzymes into the victim and then suck out the juices while the prey is still alive, similar to how a Robber Fly feeds. Whereas the adult beetles can swim and catch prey, the camouflaged larvae hunt by remaining motionless on a rock or stick and then grabbing any prey that floats or swims by. Adult beetles can stay underwater for prolonged periods by trapping air between the wings and body. The larvae breathe through three snorkel-like attachments at the rear of the body (see photo).
And then there were two!
These insects are highly predaceous at all stages of development. In some aquatic environments the Water Tiger is the apex predator (has no predators itself). In the time it took me to get my camera focused for the photograph (right), two Water Tigers had already attacked and half-devoured a third individual.
It appears that pond life is just as cut-throat as footy.
Metamorphosis 2
After a recent post, Metamorphosis, we decided to keep a few tadpoles in a container of water from our wetland, complete with water plants, rocks, sediment and a few water bugs, to follow their development. It is fascinating to watch the gradual emergence of firstly the hindlimbs, then the forelimbs and finally the shrinking of the tail as each tadpole transforms into a frog.
We’re still no closer to positively identifying the tadpoles, so we’ll just have to see what frogs appear before releasing them back into the wetland.
Below is a random selection of photos of the tadpoles in the latter part of the standard 46 stages of metamorphosis. There are at least two, and maybe more, species shown. Some photos are of tadpoles grazing (or browsing?) on the roots of floating aquatics – the fern Red Azolla (Azolla filiculoides) and the liverwort Ricciocarpus natans.
One LBJ puzzle solved
In the quest to add to my ‘Lists of Observed Things’, I have started looking at smaller and smaller things, for example springtails and micro-mushrooms. On the bird side of things, apart from the raptor that has been hanging around the house for the past month, and of which I still don’t have a photo (not even an insurance shot), I think I’ve spotted all the ‘big’ ones. So to add to my bird list, I’ll have to start photographing the LBJs (little brown jobs). LBJs are those tiny little birds you can barely see as they flit through the tree-tops, usually against the sun.
For a decade I have avoided identifying LBJs. They are hard to photograph and hard to identify (for me) even with a photograph. Last week I saw one flitting through a grove of young Black Wattles (Acacia mearnsii). Although it was not-so-little and not-so-brown, it is still classified as an LBJ because it moves with them as they mob across the landscape (LBJ by association).
The new bird app on my iPad narrowed it down to about a dozen suspects, but in the end I had to call in Geoff and Dave, the bird-o experts from Yea and Strath Creek, for a positive identification. The bird is a Jacky Winter (Microeca fascinans). The origin of the name is not known but it reminds me of a Willie Wagtail and Robin Red-breast.
On display
Last week a small flock of Dusky Woodswallows could be seen circling around the canopies of some tall Yellow Box and Grey Box trees on the steep east face of the Three Sisters, Flowerdale. Between their sallies out searching for flying insects, they would settle on branches of the trees or on bare branches of lower shrubs, which is where one was spotted spreading its wings and quivering in what was presumably a courtship display.
It was so absorbed in this display that it allowed itself to be photographed at quite close range. We have seen Striated Pardalotes engage in a very similar display in a large Yellow Box near our house.
Dusky Woodswallows in south-east Australia are migratory and most head north for the winter, so these birds would probably be recent arrivals returning to the district.
A key feature distinguishing them from other woodswallows is the white streak along the leading edge of the wings (see photo below).
Click on any of the photos for a closer look.
Vale Cato. RIP.
The animal that you can get closest to at our place (if you pretend to be looking in the other direction) is the Swamp or Black Wallaby (Wallabia bicolor). Walking at a steady pace can sometimes get you within metres of these beautiful animals. Swamp Wallabies are the only living species of the genus Wallabia. They are solitary creatures coming together only to breed. Each animal has a distinct range that they defend aggressively from other wallabies, as you can tell by their shredded ears. In fact it is this feature by which you can identify individual animals. We have five Swamp Wallabies with ranges on our property. One of these we have named Cato. Those of a certain age may remember Cato Fong, the Chinese man-servant of the Peter Sellers’ character, Inspector Jacques Clouseau in the movie Return of the Pink Panther. Cato used to hide in the Inspector’s house and attack him by surprise, so that the Inspector could keep his martial arts skills honed.
Cato (the Wallaby’s) home range covers our eastern slope and includes the dirt road and the neighbour’s steep gully. As with Cato Fong, our Cato would regularly launch surprise attacks on our car as we made our way up the road, sometimes leaping from the upper road-side bank to land seemingly within inches of our 4WD to then continue across the road and down the gully. We were ever vigilant for Cato’s next raid.
At dusk last week we were walking down our winding and steep road when a car came hurtling around the corner, way too fast for the road conditions let alone the fact there were wallabies and roos grazing on the road side. We managed to jump out of the way and the car continued at a rapid pace around the next bend. As we rounded the bend we found Cato dead in the middle of the road.
I know, given where we live it is probably just a matter of time before we all collect an animal with our cars, even if we are careful. What I don’t understand is how you can hit an animal and not stop to render assistance or worse still leave it lying in the middle of a single lane, steep and winding dirt lane for the next unsuspecting driver to confront as they come driving around the bend.
Vale Cato. You gave us hours of entertainment as we tried to predict where your next attack was coming from. RIP.
Peg basket squatters
The Grey Shrike-thrush is one bird that seems to have adapted well to human incursion into its habitat. Many of us who have had them nesting in odd places around houses or sheds will relate to this story sent in by Rosemary from Strath Creek:
“Two years ago my peg basket became the home of a shrike-thrush, its mate and later two healthy youngsters. The washing was still pegged out only metres away but I had to find new storage for the pegs. The chicks eventually reached a size where they could crawl/hop along the clothes line to be fed (meanwhile the washing had a new home).
Then disaster struck! A feral cat took the youngsters one by one. We received a trap from the ranger and caught the cat, but it was too late for that year’s brood.
Last year the basket was hung in a more secure position but didn’t attract the birds.
However, now the adults are back once again.
Does anyone experience the same excitement and pleasure as I do in providing a safe space for the birds and observing the new inhabitants? It means I have to walk up the path to the other washing line, but it’s well worth the inconvenience!”
The Grey Shrike-thrush is actually neither a shrike nor a thrush, but is in the Whistler family Pachycephalidae (also known rather unkindly as the ‘Thickhead’ family), which contains some of our most beautiful songsters. To hear some of the shrike-thrushes wide repertoire click on the audio icon below.
Sticky beaks
On sunny late winter days, a flowering Downy Zieria (Zieria cytisoides) in our garden attracts a range of insects hungry for nectar. The zieria bush is native to Victoria, but not this district. The Common Hover Fly (Melangyna viridiceps) pictured at left and below, is, as its name suggests, skilled at hovering and can often be seen probing the small flowers with its proboscis (click on the photo for a closer look). The proboscis is a hollow tube used for feeding which is otherwise kept coiled – at least in butterflies and moths – not sure about the hover fly. Hover flies are beneficial as pollinators of native plants, while their maggots prey on aphids.
As well as the hover fly, numerous feral Honey Bees (Apis mellifera), pictured below, visit the flowers. Feral honeybees, as opposed to managed honeybees, are generally considered detrimental to the Australian environment.
They are less effective pollinators of small native flowers and have been implicated in the decline of many species of flora.Their sheer numbers outcompete native insects and they are known to take up to 80% of floral resources, as well as possibly damaging the ovaries of some flowers by their size. They also, of course, occupy tree hollows (and nest boxes) which would otherwise be available for native birds and mammals.
Another occasional visitor to the zieria bush at the moment is the smallish butterfly pictured at right, which we think is an Australian Painted Lady (Vanessa kershawi), one of the first of the spring butterflies.
Same name, different creatures
When we lived in Brunswick we lived next to a household of ferals. We called them that because they called themselves that. They were invariably goatee wearing (the males), tattooed (both males and females), dreadlocked and the nicest set of neighbours you could ever want – even if the parties got a bit loud on the weekends.
Now we are in Flowerdale our neighbours are still ferals, of a different type. The motion-sensing camera set up for a week revealed several species of feral animals cavorting on our back lawn.
Both the Rabbit (Oryctolagus cuniculus) and the European Fox (Vulpes vulpes) were introduced to the Australian mainland in the 1840s and 1850s for recreational hunting. Both species have been a disaster to the Australian environment. Rabbits are prodigious eaters of vegetation. It would be OK if they tucked into the Capeweed, Thistles and Patterson’s Curse but at our place they appear to mow through all the native vegetation including the native orchids and lilies. And the foxes decimate the native fauna. The only saving 
grace is that the foxes also eat the rabbits.
Cats (Felis catus) arrived as domestic pets but sometime later were released to keep to rabbits down (go figure). They also keep everything else down as well.
Even though I far prefer living in the wilds of Flowerdale, as loud as they were, I think for overall niceness, I prefer my feral neighbours in Brunswick.
Metamorphosis
Armed with a net and bucket, we headed off to sample some dam water among the rushes to see what waterbugs were present. Sifting through the sample, we discovered a variety of little darting creatures: tiny water mites, beetles, backswimmers, waterboatmen etc. – as well as a few tadpoles, which we took back to the house to examine.
With the aid of our newly-acquired copy of Marion Anstis’s superb book Tadpoles of South-eastern Australia, a hand lens, a USB microscope and camera, we endeavoured to find out which species they were.
Tadpole identification is not easy, and requires the careful study of a range of features such as body/tail shape and size, location and arrangement of mouth parts, eyes and nostrils, pigmentation and many more. These features are used to work through a scientific key to hopefully arrive at the correct identification. Use of the key requires beginners like us to learn a whole new glossary of terms, such as flagellum, iridophores, nares, papillae and spiracle.
The amazing metamorphosis from egg to frog, which can take months, has been divided by biologists into 46 developmental stages. The tadpoles we found seem to be of two or perhaps three species and were fairly well developed, with almost complete mouth parts and hind limbs emerging.
With little confidence we decided that the tadpoles we had would develop into Plains Brown Tree Frog (Litoria paraewingi) or Whistling Tree Frog (Litoria verreauxii), which have fairly similar tadpoles – and Pobblebonk, aka Banjo Frog (Limnodynastes dumerilii). We know from their calls that all of these frogs frequent the dam, but clearly we need more practice in tadpole ID!
Here come the clowns
I was driving deep in the heart of Flowerdale recently when I noticed sitting in the middle of someone’s lawn what we call in our household a ‘Clown bird’ (pictured left). It is in fact a Masked Lapwing (Vanellus miles) but with a face like that we prefer our name. I had seen them before but never around our neck of the woods. The bird pictured is of the subspecies novaehollandiae identified by the black marking around the breast.
Masked Lapwings are raucous birds and very territorial, particularly in nesting season. They will nest in highly open spaces. As I approached, 
camera in hand, the bird staggered off pretending a broken leg and leaving a clutch of three eggs and a chick (pictured right). The nest consisted of, well, nothing — barely a scrape in the ground. I wondered what evolutionary tactic has led this bird to lay eggs on the ground in such highly visible areas. The chick is normally well camouflaged against sticks, leaf litter and soil – but not on a lawn.
Chick. What chick?
The Masked Lapwing used to be called a Spur-winged Plover but the name was changed as it was shared by a totally different bird on the African continent. In the photo left you can clearly see the yellow spur protruding from the wing. The spur, which is non-venomous, is used by the bird when defending its territory or chicks. In fact the species name miles is Latin for soldier, probably referring to the weapon on its wings and its aggressive attitude. On a second visit the bird remained sitting on the ground and pretended there were no chicks for miles. However a close look underneath will reveal another pairs of legs. I wonder where the chick is?
It might look like a clown, but watch out if you get too close and there are young to protect.
Focus On Fauna 