Mt Rogers' approach to summer 2009

Within two November weeks, the lush greenness of spring growth was replaced by the beiges of summer. Grass flowers dried rapidly. Any shed seeds may have provided food for birds such as Finches and Rosellas. It would be comforting to think that birds’ digestive systems crunch-up weed seeds and are kinder to the seeds of plants we’d like to encourage. Unless we keep to the paths ourselves we’re likely to disperse seeds as they hitch a ride on Velcro, socks, laces, fabric and amongst our dogs’ hair. We don’t even need a hand-lens to see the extraordinary structures seeds have developed to spear or screw their way through fibrous material. Millions of years of subtle changes, trial and error ... evolution!

The swathes of grass awaiting mowers are being attended to in priority-order ACT-wide. “Above” the gravel path there have been many hidden treasures amongst the grasses. In Mt Rogers’ more intact habitats we’ve had glimpses of the richness and miniature beauty of the region’s natural temperate grasslands that we’ve altered through farming and continue to build-over. Whilst checking the progress of clumps of Blue Grass Lilies I came across Onion orchids of the Microtis group. How many times have I walked there in spring and not been observant enough to find them?

Shall I cheat and say “most ground orchids don’t flower every year”? Being green they’re not even as obtrusive as the white Early Nancy lilies that Mt Rogers welcomed at the end of winter. Both Black Mountain and Aranda Bushland have had magical displays of yellow, pink, bluey-purple orchids this spring. There were even the harder-to-find Spider and Gnat orchids pointed out to us by those who guided walks into these orchid-rich reserves.* Perhaps the grazing stock and the scouring of the terrain as our suburbs were built destroyed the Mt Rogers orchid population’s tubers and fleshy roots. There is one blue Sun orchid that I know of. It produced several flower-spikes but I’ve not seen the short-lived flowers actually open. It’s apparently self-fertile but would the minute seeds find the correct fungus to stimulate germination? Sun orchids have fairly-conventional-looking flowers but the amazing shapes of the ACT’s other ground orchids species show the complexity and intricacy of the plants’ structure as each strive to attract specific native wasps, gnats, male sawflies and other insects as pollinators.

The Frogmouths intrigued us again but they have now moved away from their nest site in Schwarz Place. Being literally off the beaten-track fewer Mt Rogers folk were able to monitor their progress daily. Gales blew away the first twigs of their nest in last year’s tree so the parents re-located to a fork near their roost site. The male incubated the eggs during the daytime and later sheltered growing chicks when hatched. The female’s days were spent roosting in a nearby tree or, unfazed, above the gate into the house.

Over several mornings in early November the calls of Superb Parrots were heard and birds were seen flying over the nearest suburbs. The arrival of about thirty of the endangered parrots in September has generated more questions than answers. Members of the Canberra Ornithologists Group have been very grateful for reports of sightings (including numbers and male-to-female ratios). Our seeing only males during a trip to Mulligans Flat on 7th November suggested the females were incubating eggs in the reserve's hollow trees. Enthusiastic golfers phoned-in sightings from Belconnen Golf Course’s over-wintering group of seven Superbs, but where do they forage during the day? How many Superbs will come to Mt Rogers and the ACT around Christmas time?

Several sightings of Bearded Dragons have been mentioned. They’re quite different from the iconic Frilled-necked lizard of inland Australia but we can still enjoy their extended beard and yellow mouth during displays of fierceness. Once warmed-up they seek grasshoppers, beetles, moths and other invertebrates as well as fruit, berries and other plant material. Apparently the female digs a tunnel and lays over 30 eggs before refilling the hole … who’d be lucky enough to witness that?

In contrast Eastern Blue-tongued lizards have twelve live young and they’re efficient controllers of snails. It would be good to have them in our garden but next-door’s cats would be a threat. Other invertebrates, berries and fruits are included in their diet. January brings the Herpetologists’ Snakes Alive display to the Botanic Gardens. It’s a great opportunity to meet our local reptiles safely and to see Corroboree Frogs, young Crocodiles and more venomous snakes. Please ensure your dogs are under control this summer so our lizards are safe and Mt Rogers' snakes don’t claim victims. Also, check when the vets are open in case a snake-bite does occur.

Species of Brown butterflies seem more numerous this summer. Grasslands and Woody Grasslands are their habitat preferences. Their caterpillars will feed on several species of our grasses and you may see gatherings of the butterflies on the higher parts of the ‘reserve’ as males hope females will meet them there for mating. This phenomenon is ‘hill-topping’. Have you ever seen butterflies gathered around puddles? They are seeking chemicals near the shallow edges of the water. Yesterday I came across a lone paper daisy plant shining bright yellow in the sun. (There’s a great display of these daisies on the southern edge of The Pinnacle’s woodland at the moment) Butterflies complete an attractive picture if they’re found visiting these daisies when the camera’s ready!

We seem to have had quite a few Sparrows around home in recent weeks. They almost hover under the eaves at times trying to grab spiders. Yesterday there were several gleaning insects, with Silver eyes, amongst the rhubarb leaves and stalks. On Mt Rogers there’s a particular area frequented by these relatively innocuous introduced birds. Their untidy nests seem to be made mostly of grass. I’ve not even found a Friar bird's nest this year but I’m sure there are numerous brilliantly-made structures around the hill. Many small native birds bind grasses, leaves, bark and lichen pieces together with spider silk. Some even go to great lengths to decorate their nests but that’s partly a camouflage technique where nests are on branches or hanging amongst foliage. Can you imagine trying to weave a home with these natural materials and with “no hands”?

References

• David L Jones Field Guide to the Orchids of the Australian Capital Territory, Canberra, NPA, 2008 . Before moving from Melba closer to the coast David was a regular Mt Rogers walker.
• Bennett, Ross Reptiles and Frogs of the Australian Capital Territory, Canberra, NPA, 1997
• National Parks Association of the ACT is also working towards publishing a guide to insects of our region…great initiative.

Rosemary, Convenor, Mt Rogers Landcare Group