The flies declined with the temperature though mozzies still arrive in unpredicted squadrons. Appearances of B.B.H.s (Bloody Big Huntsman) decreased, though that's more about shyness than numerousness. There's probably one reading over my shoulder right now but I refuse to turn around unless it taps me on that shoulder.
As summer became autumn, I started to feel comfortably acclimatised to life in the Hills. With two healthy dogs, poo picking is a fairly constant pastime and I saw the range of small spiders and insects living quietly among the blades of grass. Every now and again I noticed a few lumps of mud near small vertical tunnels in the soil. Having grown up in a Sydney backyard, I passed these off as signs of spiders and instituted a policy of wilful ignorance.
Until my wife pointed out the mud tubes rising from the lawn.
From the safety of our bedroom window I noted that one tube was several inches high and solidly constructed from layers of mud. There was a smaller version closer to the old water tank. I took a few pics and asked around over the next few days. My fear was that someone would casually inform me thus :"Oh, that's the nest of the endangered “Gippy bird eating wasp” or some such fresh horror foretelling abandonment of our home.
On the other hand, residing near the edge of the known habitat of the endangered giant Gippsland earthworm raised hopes that my mud tubes evidenced their proximity. Or perhaps the tubes were some sort of frog dormitory. A few “people who would know” didn't. Ad hoc observation of the tubes showed no sign of occupancy though they were growing. The dogs had no interest so I decided that there was nothing edible at large during the daylight hours.
Eventually I resorted to Professor Google. The mystery was solved by two phrases within four clicks. As well as the famously endangered giant earthworm, the soil around here is home to another mysterious creature. As if the spiders and snakes weren't enough, we now had a lonesome burrowing crayfish.
“Crayfish” usually conjures thoughts of yabbies. Cherax destructor is the most common yabby found in dams. Burrowing crayfish belong to the genus Engaeus. These crayfish live most of their lives in a labyrinth of underground burrows. Piles of excavated mud are often the only sign of their presence. West Gippsland is home to nine different species of these critters and five of these are considered in need of conservation action to halt their decline.
I suspect that our landlubber crayfish is Engaeus urostrictus which burrows till water fills a small chamber at the bottom of a branching system that can cover up to half a square metre. As the urostrictus digs, it brings pellets of soil to the surface to build those little stacks on the lawn. The crayfish spends most of its life in that chamber feeding on decayed plant matter, roots, worms and insects. Some species live alone, though others are communal. Juveniles hatch in late summer and can remain in their parents' burrow or move on to start a new life.
Burrowing crayfish are vulnerable through fire, drought, the actions of grazing cattle, erosion and loss of habitat. As always, it turns out that they have more to fear from me than I have from them.