Perth is built on a swamp. These days there’s not too many swampy areas left because over 150 years they’ve been filled in and cleared for development. The most recent demise is the swamp I loved to drive past on my way home. Now I drive past a building site on which is appearing the southern hemisphere’s largest Ikea store. :(
This swamp probably hasn’t been in pristine condition for a long time. It was surrounded by trees, but it was probably also filled with weeds and assorted invasive species. When I was a kid, horses grazed on the area where Ellen Stirling Boulevard now is. Stephenson Avenue is currently a track for the builders to drive in their trucks; I guess it will be asphalted when construction is complete.
The carpark in the top right hand corner of the aerial photo has a park to the northeast with a couple of ponds, a war memorial and some replantings of trees (to make it look like it was never cleared). The drainage ditch runs past this park, goes under Mitchell Freeway and comes out 200m from Sarich Ct. The ditch and the strip of land to the south east of it (to Sarich Ct) have survived the construction. The ditch runs southwest, going under a few more roads, until it gets to Herdsman Lake which is a Regional Park and so won’t be filled any time soon, although over the years houses have been crowding its edge. At one edge is the Herdsman Lake Wildlife Centre, managed by the WA Gould League and the WA Education Department. They provide bird walks, information nights, night stalks, and wildlife excursions. School classes can go there to learn about the lake and its ecology and wildlife (which I did when I was in school).
While Herdsman Lake is a significant wetland and wildlife sanctuary located within the Perth metropolitan area, it faces a number of management problems such as polluted and nutrient enriched stormwater and groundwater inputs, areas of disturbance, significant weed invasion and the presence of introduced animals.
It’s not all doom and gloom for wildlife, though. Tiger snakes (Notechis ater) are common at Herdsman Lake and frogs, which you’ll only come across (or more likely hear) at night. Birdwatcher Frank O’Connor says there are also Long-necked Oblong Turtles (Chelodina oblonga).