A small group of seven members met for our March 22 outing. Erskine Lakes, situated in the suburb of Erskine in the City of Mandurah, is a reasonably large area of green open space containing two freshwater lakes. Situated close to the Peel-Harvey Estuary, these lakes are used by many species of water birds, while the trees and shrubbery provide habitat for woodland birds.
We commenced our walk in the direction of the smaller of the two lakes, at the southwestern end of the park (left, bottom left-hand corner). We had not gone far when Daniel inspected the trunk of a large eucalypt, looking for insects, and pointed out where termites were moving up the trunk using one of the vertical grooves in the bark. This was to be a common find on the trunks of many of the park’s larger eucalypts. Close by, on the trunk of a Swamp Paperbark (Melaleuca rhaphiophylla) Daniel noticed an unusual fly that was happy to be closely inspected and photographed. It would later be identified as being from the genus Lamprogaster but the species could not be confirmed. The bark of the paperbark was showing signs of damage caused by various beetles and bees.
We continued around the smaller lake, which was surrounded by thick vegetation (mainly Melaleuca sp.) while Typha orientalis dominated the edges of the lake itself. Pacific Black Ducks, Eurasian Coots, Purple Swamphen and Australasian Grebe were spotted on the lake or its margins. As the vegetation opened up we had a better view of the lake and spotted a Great Egret stalking the shallows. At the southern end of the lake the vegetation alongside the path consisted of Seablite (Suaeda australis), Chenopodium album and Berry Saltbush (Rhagodia baccata). Weeds were present, including several types of Conyza (white flowers), and thistles (yellow flowers). As we moved further around the lake it changed to being a wetland dominated by Swamp Paperbarks (Melaleuca rhaphiophylla). Angled Lobelia (Lobelia alata) was flowering in the shade of the Melaleuca rhaphiophylla on the edge of this area. In the canopy we spotted many small birds, of which Striated Pardalotes, Grey Fantail and Silvereyes were identified. Two species of dragonflies were also spotted in this area, the Blue Skimmer (Orthetrum caledonicum) and Australian Emperor (Hemianax papuensis).
We emerged into the parkland and made our way counter-clockwise around the larger lake. This lake was showing signs of an algal bloom: the water was very green in colour. Australasian Grebes, Eurasian Coots and Pacific Black Ducks were again spotted on the water, together with some Little-black Cormorants. The lake has three islands where the dominant trees are casuarinas, which in spring are favoured nesting sites for Australian Darters. There was no nesting activity during our visit but there were still many darters resting and drying their wings. There were also some large dead eucalypts on the island that were also being used by the darters as roosts. One of these trees made a fantastic sight, as 13 Yellow-billed Spoonbills (in addition to several darters) were spotted on its branches. The spoonbills appeared to choose some precarious branches on which to land and they often struggled for balance in the wind. A single White-faced Heron was also spotted on one of the trees and Australian White Ibis were also present.
As we walked further around, we spotted a pair of Australasian Grebes that appeared to be surfing the waves produced by one of the large aerating fountains. The grebes would swim, or sometimes dive and surface, in close to the fountain—apparently just to ride the wave out. Tree Martins were constantly flying above the lake and its surrounds while under the park’s trees we spotted some other birds, such as the Willie Wagtail, Common Bronzewing, Crested Pigeon, Magpie Lark and Australian Magpie. A pair of Grey Currawongs flew noisily overhead: an unexpected sighting. Ringneck Parrots were common, and a single male Red-capped Parrot was spotted in a tree near one of the surrounding houses.
Daniel Heald supplied a list of invertebrates found on the walk. These included a Jovial Jumping Spider, Chironomid Midges, a Zebra Spider Wasp and other Hymenoptera including feral European Honeybee hives and metallic blue parasitic wasps. He also spotted Crematogaster ants, and Brown Coastal Ants.
Having walked around the lake, we made our way back to our starting position and set up our chairs (while adhering to the required social distancing rules) for a well-earned cup of tea. During morning tea we added to our bird list with sightings with a Laughing Kookaburra, Whistling Kite, Australian Pelicans (flying over) and a Grey Butcherbird. A total of 27 bird species were spotted and this data was entered into the Birdata app.
It had been a new place for most of our group. It also demonstrated how valuable these areas of green open space are within suburbia, especially if they contain wetlands or lakes. They provide habitat for various birds, insects and other fauna.