Water features have everywhere in Berowra this last year. With half the suburb’s roofs smashed to bits by golfball sized hailstones just before Christmas, an ice-storm followed an hour or so later by torrential rain, lots of those water features were indoors and distinctly unwelcome. In a suburb that has come to be known over the months of waiting for insurers to come to the party, as “Tarpaulin Heights” we got off relatively lightly, with our indoor water feature making only a cameo one-time appearance.
Inundation was the origin of our new outdoor water feature as well. Thanks to topography and a inexplicably ruptured stormwater drain – I did fear at one time it was an inexplicably ruptured sewer, so I’m thankful for small mercies – when the rain comes down in Berowra, most of it seems to come through our backyard.
The weather pattern in Australia now, even here on the coastal fringe where the trees are still alive and there is grass, which is sometimes even green, seems to be long dry months punctuated by occasional periods of quasi-apocalyptic rainfall. So catching some of the run off and making some use of it seemed like a good idea. And then there’s my fantasies about frogs.
So in December last year, I dug a big hole, downhill from the stormwater drain and uphill from my veggie garden. Deep holes are not easy to dig on Hawkesbury sandstone. I was aiming for a depth of no more than 30cm, since I really didn’t want to have to fence my pond, but even 30 cm was a push. I rationalised the shallowness of the hole with reference to the gently sloping edges that would allow the amphibians of my dreams to rest comfortably on the edge of the pond. Not a very convincing excuse to avoid further shovel work.
I lined the hole with a few centimetres of sand from the local garden centre. Carpet underlay is sometimes recommended for a layer underneath pond liner but I went an old trampoline mat, since that’s the kind of thing I have lying around in my shed. Retrospectively I’m not sure that was a great idea. On top of that I put down rubber pond liner – quite a lot more expensive than vinyl, but not plastic and, in a household full of underused bikes, I figured, quite patchable. In theory. Underneath that footlingly small pond is six square metres of heavy duty rubber.
Sensible guides to pond making recommend that you set up your fountains and filters properly, then add native plants, give it a week or so and then add fish. Â However, a couple of days after setting up the pond with a solar powered aerator, native grasses (Carex fascularis and Schoenoplectus Mucronatus) and pond plants (Marsilea mutica, and if memory serves, Nymphoides montana) I spotted a huge number of wrigglers frisking gaily around their new habitat, and decided we would need to go fish shopping.
Our neighbours had demonstrated their true commitment to biodiversity by not just accepting but actively welcoming the idea of frog mating calls 24-7 outside their bedroom windows. However, we thought adding a vast number of mosquitoes to the local ecosystem might not necessarily go do down equally well. We decided to buy two pairs of pacific blue eyes to populate our pond, while we waited for other insect eaters – frogs and dragonfly larvae and the like – to arrive.
Pacific blue eyes are small fish – less than 8 cm in length and usually much smaller – that are keen mozzie eaters but not big enough to devour frog spawn. They’re locals all up and down the East Coast, inhabiting both fresh waters and estuaries, so not too fussy about water quality. Our local aquarium shop had a stock of them, though the staff were pretty clueless about which fish were native and which were not, offering us white cloud minnows (originating in China) as a possible alternative. We took our two pairs of tiny, quasi transparent fish home and Ms 12 and good friend and frog lover from next door carefully introduced them to the pond, taking time to equalise the temperature of the water to minimise shock.
All that happened around midday on December 20, the day of the hail storm and subsequent torrential downpour. Within hours of settling our blue eyes carefully into our little pond, our backyard looked like this:
Ms 12 was desperately trying to block the exit from the pond, but I think realistically the Pacific blue eyes were halfway to Berowra Creek by this point. There was much weeping and gnashing off teeth, counterbalanced, on my part at least, by a certain smugness that I hadn’t bought white cloud minnows or gambezi fish or something else that you wouldn’t want to end up in your local waterway.
Of course, what with the water being murky and the fish being small, shy and in essence invisible, we weren’t quite sure if we still had pacific blue eyes or not. Rather than waiting for the mosquito murmuration that would tell us that we didn’t, and with an eye to diminishing the level of weeping, we went back to the aquarium shop for yet another couple of pairs.
That was a nearly a year ago now, and there have been no further sightings of the fish. The solar powered bubbler carked it in another downpour, along with the rainbow nardoo which I accidentally ripped out while clearing out excess algae during winter months.  But the wriggler count has stayed low and the pond has done pretty well as a habitat. Not to mention the fabulous opportunity it’s given me to buy new plants (full list at the bottom of the blog)
On the down-side, I’ve been surprised how often I have to top the pond up with water. Either it has a surprisingly high level of evaporation for a pond in shade much of the day or the logs and rocks I dragged around the yard to make a naturalistic edging have punctured the rubber lining in some mysterious but annoying way. Perhaps there’s a reason people don’t recommend using old trampoline mats underneath your pond.
One way or another, I have become a pond slave. I’m constantly ruminating on where I’m going to get my next hit of non-chlorinated water. The many many hail-holes in our gutters all have a bucket underneath them and I usually have a bucket of tap water off-gassing somewhere around the yard. I have heard rumours there may be better ways of collecting rainwater than this. Working on it.
It was lovely to see the blue banded bees the visiting koala bells and dragonflies hovering over the water, but we’ve had to be patient with the frogs. The approach you take to getting a frog is a bit like the approach 1950s women had to take to getting a boyfriend – make yourself appealing and wait. Chytrid fungus is devastating frog populations across the world and if you go and collect frogspawn or tadpoles you can help it spread. So we waited.
A few months back I heard the distinctive pock of a striped marsh frog in amongst the waterside foliage. I was beside myself with excitement, but after I let the chooks out to freerange for the afternoon, the marshie disappeared. Troubling. It seemed like having both chickens and frogs might be an impossible dream.
But by the end of winter, another striped marsh frog was in situ, vamping the local females with the alluring noise of a loudly dripping tap. Perhaps this male was too large to be wolfed down by the chooks on their visits to the pond for a drink and an insect snack.
And, glory be, last week we spotted a couple of handfuls of tadpoles, huddling at the bottom of the pond near some algae. I am now officially a frog mumma, as my daughter said. But I’m not feeling too much eco-smugness. According to the Australian Museum, the striped marsh frog is an unfussy beast – it likes a pond but even a polluted ditch will do. Apparently they’ve been found breeding in dog’s drinking bowls.
So no pressure. The bar has been set low for us as aspiring frog parents. Let’s see how low we can limbo.
Native plants in and around our pond.
Artenema fimbriatum (koala bells) – blue or pink flowers in summer.
Bacopa monnieri (Brahmi, memory herb) – small white flowers. Grows in and near water – edible plant.
Carex fascularis (tassel sedge). Grows in moist to wet soils in part shade, up to a metre high.
Centella asiatica (Gotu kola, pennywort). Edible plant. Grows in part shade in moist soils.
Cissus Antarctica (kangaroo vine) Â Â Planted in the drier area around the pond.
Doodia aspera (prickly rasp fern). Grows in moist areas, nice pink new growth.
Finicia nodosa
Hibbertia scandens (guinea flower)Â Â Flowers in shade,
Isolepsis cernua (Live wire) – low growing grass with interesting bright seed heads.
Juncus flavidus (billabong rush)
Libertia paniculata – in moist areas near pond in shade, alongside ferns. White flowers in early spring.
Lythrum salicaria (purple loosestrife)- growing in drier areas near pond. Dark purple flowers in autumn. Dies down in winter.
Marsilea mutica (rainbow nardoo) – pond plant. Beautiful patterned leaves.
Microlaena stipoides (weeping grass) – grass surrounding pond. Grows well in shade in damp or dry conditions.
Mazus pumlio (swamp mazus) – grows in moist soil. White flowers in autumn.
Nymphoides montana – pond plant with beautiful yellow flowers.
Peperomia (native) – native succulent that grows well in shade.
Poa labillardiere (tussock grass) – grown in drier areas around the pond
Schoenoplectus Mucronatus – rush growing in the pond. Interesting spiky seed pods.
Tetragonia tetragonoides (warrigal greens) – edible plant. Grows very well in damp or dry soil in part shade. Delicious to humans and also chickens.
Tripladeua cunninghamii (bush lily) – grows well in part shade, pink flowers in spring. IÂ killed it.