Werribee Gorge Excursion Sunday 8th July 2012
The frosty morning cleared to a sunny day as 11 field nats joined leaders Elspeth and Paul at Ballan. We drove along Ingleston Road and parked at the rail crossing. A flock of Crimson Rosellas flew off as a train to Ballarat passed.
Our first walk was along the Western Bluff track on the southern edge of Werribee gorge State Park. The track follows a dry ridge with stunted Red Ironbark and Golden Wattle. Most of the other eucalypts have died during the past dry years. The predominant ground cover was bright green moss with scattered shrubs and herbs including Saloop Saltbush, Large-leaf Bush-pea and Twining Fringe-lily. Further along the track low-growing ironbark were covered with Coarse Dodder-laurel which carried many flower buds. From a lookout we could see The Island – a steep-sided, flat-topped hill surrounded on one side by the Werribee River and on the other side by Myrniong Creek. A Wedge-tailed Eagle was soaring across the valley near the Western Freeway. On the walk back to the car we saw Striped Greenhood in flower. Other orchid leaves were seen in many places. Buff-rumped Thornbills, a male Scarlet Robin and White-plumed Honeyeater were some of the birds seen.
The morning tea stop was at Lions Club reserve on the banks of the Werribee River in Bacchus Marsh. A magpie carolled as we enjoyed a cuppa.
The geological highlight of the day was a visit to the Council Trench reserve at Darley. It is the only known outcrop of Triassic aged sedimentary rock in Victoria. The 210 million year old sediments were deposited in freshwater and consists of massive, contorted, iron-stained sandstone with some conglomerate banding. Further information about the reserve can be found at http://www.vic.gsa.org.au/Heritage/Case_Studies/Council_Trench.html. The reserve is a Rocky Chenopod Woodland Environment Vegetation Class. Shrubs included Golden Wattle, Sweet Bursaria, Tree Violet and the Bacchus Marsh variant of VarnishWattle. Small-leaved Clematis was beginning to flower. Herbaceous plants noted were spear grass, New Holland Daisy, and Ruby Saltbush. We watched a glider being towed aloft by an aeroplane and a Wedge-tailed Eagle gliding in the sky.
Meikles Point Picnic Area in Werribee Gorge State Park was our lunch stop. Superb Fairy-wrens came around the table looking for crumbs while a Yellow Robin perched in an adjacent tree. As we began to walk upstream along the Werribee River we saw a male Golden Whistler, Silvereye and Grey Shrike-thrush. The track follows a water channel constructed in the 1920’s to supply water to Bacchus Marsh. The track has a gentle grade but from the edge falls steeply down to the river. Tillite, a rock deposited by Permian age glaciers is exposed in places along the channel. In places the folding and faulting of Ordovician rock was clearly visible. A rat was seen amongst the vegetation but quickly climbed up the rock face and disappeared. A pair of feral goats was seen on the opposite side of the river. The male had a spreading set of spiralling horns. As we approached the cliffs where Peregrine Falcons regularly nest some people observed a falcon flying swiftly overhead.