The highland yabby is about as elusive as the ghost of a yeti.
There is an unlikely creature that lives in the buttongrass moorlands of sub alpine Tasmania. The highland yabby, or burrowing crayfish, digs holes in the soil which fill up with water, and they live within these holes most of their lives. I’m not sure how far down their holes may reach into the ground, but I imagine there to be more of a horizontal maze rather than a vertical one, as their habitat is often underlaid by extensive rock shelves. Nevertheless, some of these yabby hole systems, often high up on ridgelines, can be extensive. Yabbies tend to come out of their holes upon heavy rains and scavange around for rotting plants among other things…
You’d think that living life as a yabby in a wet hole somewhere high up in the mountains on some gnarly old ridgeline would be somewhat peaceful and serene. Surely those yabbies wouldn’t have much to worry about?
Well, someone told me once that the big yabbies eat the smaller yabbies and so that sometimes, you can get these giant yabby queens and kings, living in their underwater warrens, who reign supreme for a while, until some bigger yabbies comes along.
I don’t know if I want to believe that story completely. It can’t be all about survival. Surely the yabbies have some catch ups that don’t involve eating each other? It really can’t be such a bad life.
Unless of course, the wet hole turns into a dry hole. If it doesn’t rain, the ridgelines are the first to dry out. They are exposed to the wind and the water runs off, to lower places. Without water, the yabbies dry up as well. They need water in their little holes to survive. So if their holes dry up they would only have one option. They would have to undertake a journey down the hill, towards more plentiful ground water, but this is bound to be hazardous and fraught with many dangers.
In the eight years that I have lived in Tasmania, I have only seen these bluish creatures once or twice. I have walked past thousands of their homes, those little holes in the ground about one inch in diameter. And in the eight days that I spent on the range depicted in these photos, I drank only the water that I managed to siphon out of the ground using my yabby tube. I remember the water tasting a bit shrimpy on some of the days, and it gave me some strange hand tremors a couple of times, but I never got sick from it. Luckily for the yabbies, the surrounding groundwater means that their holes fill up with water very shortly after they are drained by cheeky bushwalkers.
Long live the highland yabbies!
-A.S. 5/2/22, Lenah Valley.
