Report of Kwinana Rockingham Mandurah Branch 21st March 2021
The March field outing was to Bibra Lake and ten members met at the main carpark on a warm, sunny morning. At this time of the year, Bibra Lake is usually a great place to see wetland birds as it generally still holds good water levels after surrounding ephemeral lakes have dried up. However, we were disappointed to find that Bibra Lake was almost dry, with only a thin stretch of water on the western side of the lake remaining. In the distance we could see that both bird hides on the eastern side of the lake looked out onto a dry lakebed.
We made our way down to the small viewing platform to see what birds were still using the lake. On our way to the platform, an Australian Hobby flew into a large tree at the side of the walking track. This would be the only raptor sighted. From the platform we spotted two Little Egrets hunting for prey along the edge of the water. A small number of ducks were still present; these included Pacific Black Duck, Grey Teal, Australian Shelduck and Musk Duck. Australasian Grebes, Eurasian Coots, Silver Gulls, Purple Swamphens, a White Ibis plus a White-faced Heron were also present.
We then walked south along the walking track. Up in the trees, Rainbow Lorikeets were common with many coming and going from nesting hollows. Little Corellas, Australian Ringnecks, Red Wattlebirds, Willie Wagtails, and Australian Ravens were also spotted amongst the numerous large trees. With birdlife in short supply, our attention was drawn to the efforts of Daniel and Otto Mueller who were busy looking for insects in the shrubbery.
At the base of a large Eucalypt Daniel spotted some caterpillars of Tube Concealer Moths (Hemibela sp.). The caterpillars protect themselves by living inside a tube that they carry with them as they move around. They move into bigger tubes as they grow and will also pupate in the tube. A small jumping spider was also seen in this vicinity. After following the track for a short time, we turned around and made our way back to the car park. A lone, Yellow-billed Spoonbill was seen foraging along the thin stretch of lake as we passed by the viewing platform.
A Tube Concealer Moth Caterpillar’s tube casing
Photo credit: Colin Prickett
We then made use of the picnic tables to have morning tea. A young Grey Butcherbird flew down to join us, possibly expecting some tit bits. Over morning tea, we reflected that none of us could remember seeing the lake as dry as this and that it is quite disturbing since it typically provides habitat for thousands of water birds and waders at this time of the year. It is to be hoped that Perth receives good winter rainfall this year such that Bibra Lake is restored its normal condition with good levels of water through next summer.
Our final bird sighting of the day came as we were packing our cars to head home; two Pied Stilts were foraging in the shallows. A total of 19 bird species was all that we recorded; this would be the lowest total by far in all of our visits.