Friday, April 24, 2009

Our frog pond, then and now.

Eighteen months ago, we put a pond into our garden. As I was working on it today, cleaning out algae and overgrown pond plants, I wondered what it would be like to compare then and now. It's quite a contrast!

September 2007

April 2009 -- It's a jungle out there.

Edited to add: This is the link to my old website, in which I follow the process of building the pond. Lots of trial and error!

We have a number of frogs living there, but only two species so far.

Crinia signifera
, the Common Froglet:

...and the ubiquitous Limnodynastes peronii, Striped Marsh Frog:

Frog images: Wikipedia

Perhaps not a wildly diverse range of species, but I'm just delighted to have them living here. And we have to compete with the creek behind our property, so we're lucky that they decided to move in!

A Procession of Caterpillars

This morning, while walking the dogs at our local park, my husband spied what he initially thought was a ridiculously long worm rivalling the dimensions of the Giant Gippsland Earthworm.

Caterpillar Procession: Ochrogaster lunifer

But on closer inspection, he realised it was a procession of caterpillars....

Caterpillars: Ochrogaster lunifer

These are Ochrogaster lunifer, commonly and sensibly known as Processionary Caterpillars and found across much of Australia. The procession was two to three metres long, consisting of nearly seventy individuals.

During the day, these caterpillars nest communally on the branches of the plants that form their diet: Acacia species. By night, they eat, eventually completely defoliating the tree, and then move on to find another.

They travel as they were this morning in a search for a suitable area in which to metamorphose into moths. It makes a lot of sense for them to congregate in this manner, as by appearing to be one large organism, they are less attractive to predators. In addition, their hairs (and those of the adult moth) can cause urticaria, a painful and persistent rash, also a good form of deterrence against anything considering them a potential lunch.

Adult moth.


Tuesday, April 14, 2009

Swamp Wallaby

Another garden visitor, but one far more common than last post's diamond python. This is a swamp wallaby, Wallabia bicolor.

Swamp wallaby: Wallabia bicolor

I took this photo from my study, overlooking the driveway. By the look of her, she's carrying a joey in her pouch.

Swamp wallabies are found throughout the east coast of Australia, their range extending around the coast to south-western Victoria. Their conservation status is secure, but they are less prevalent than they were, due to loss of habitat. They prefer dense forest undergrowth or sandstone heath.

They are the only species in their genus, it being suggested that they diverged from the genus Macropus some 6 million years ago. Unlike other wallabies, this species tends to eat small bushes and shrubs, rather than simply grazing on grasses. This, of course, is why my garden currently resembles a plastic tree-guard plantation. It's an ongoing battle to get my plants large enough to escape the wallabies' predations!

They breed throughout the year, often suckling an older joey while another is still in the pouch. Their gestation period is around 35 days, and the pouch period another nine months. Swamp wallabies grow to 66-85 cm in height, plus about the same length of tail, and weigh 13-17 kilos as adults.