Pathway · about 20 minutes · 6 steps
Reading absence
Learn the hardest skill the book asks — seeing what is no longer there, from a paddock to a fence-line to a suburb.
Most nature walks teach you to notice what is there. This one teaches you to notice what isn’t — and trust that absence as evidence, not scenery. Start with the method itself: the shifting baseline and the extinction debt, the two ideas that let you read a paddock like a detective reads a room. Then walk the scale of the loss outward. The grassy woodland that once floored the whole Adelaide Plains, down to a scattered four per cent; the tussock grasses that floored that woodland, down to less than one per cent; the bilby, gone from the district entirely and the sharpest single case in the book; the southern brown bandicoot, the family’s last survivor, still here but only just; and the blue gum, standing alone in a paddock or a street, the lone witness to all of it. Each stop is smaller and closer to home than the last.
Take it with you. Next time you pass a lone paddock gum or a fenced verge of scrappy grass, stop and ask what used to stand around it. Close the page and go outside.
- Reading absence — The hardest skill this book asks of you — seeing what is no longer there: the vanished mammals, a baseline that keeps sliding before anyone notices, and debts still quietly being paid.
- The vanished grassy plains — The open blue-gum-and-grey-box grassy woodland the colonists found across the Adelaide Plains is almost entirely gone — learn to read the lone paddock tree, the fenced verge and the roadside grass strip as the last four per cent.
- Spear-grass & wallaby-grass — The tussock grasses that once floored the whole of the Adelaide Plains under scattered gums — now the most vanished habitat in the book, surviving as less than one per cent of its former self in scattered fenced scraps.
- Greater bilby (the lost suburbanite) — The long-eared burrower that once out-numbered rabbits in trappers' snares at the edge of Adelaide, and is now extinct across the whole settled south — the sharpest single case of reading absence.
- Southern brown bandicoot (the last of the dynasty) — The last surviving member of the whole bandicoot-and-bilby family left in the Mount Lofty Ranges — a rabbit-sized digger holding on in a few wetter, scrubbier reserves, kept there only by ongoing fox control.
- South Australian blue gum — A big, wide-crowned gum, scattered now across paddock and street rather than standing in the grassy woodland it once dominated — and, in winter, one of the range front's few working nectar sources for the birds that pollinate it.
The end-check — put it together
You've walked the steps. Now answer these from what the pathway taught, not from the pages — getting them here is what tells you it stuck.
Frederic Wood Jones recorded in the 1920s that only thirty years before, rabbit trappers 'even in the immediate neighbourhood of Adelaide' were taking more bilbies in their traps than rabbits — and rabbits were already the continent's most notorious pest by the 1890s. What does that comparison tell us about the bilby's former status on the Adelaide Plains?
Rabbits were already a continent-scale plague by the 1890s, so out-trapping them at the very edge of the city is only possible if bilbies were themselves extremely abundant there — this is the primary evidence for the bilby's former commonness on the Adelaide Plains (Wood Jones 1923-25). It is also why the bilby is the region's benchmark case for reading absence: an animal that was ordinary within living memory can vanish so completely that the next generation forgets it was ever there, the shifting baseline at its starkest.
The southern brown bandicoot still turns up in a handful of wetter Mount Lofty reserves, but the guide calls this 'extinction debt in progress' rather than a simple survival story. What does that mean?
Extinction debt describes a population whose long-term loss was already set in motion by past habitat clearing and fragmentation, even though some individuals are still present now. For the Mount Lofty southern brown bandicoot that debt is being actively serviced, not paid off: the recovery plan judges the population unlikely to persist without sustained fox baiting in its remaining wetter, scrubby reserves, so its current presence is management-dependent rather than self-sustaining (Dept for Environment and Heritage SA 2004; Szabo et al. 2011).
A single South Australian blue gum stands alone in a paddock, flowering heavily in June while almost everything else nearby is dormant. Why does that one winter-flowering tree matter so much to the region's honeyeaters and lorikeets?
Southern Australia hands most of its pollination to birds rather than bees, and on poorer soils flowering concentrates in the cool months precisely because so little else is blooming then, so honeyeaters and lorikeets move to track it (Ford & Paton 1986). Blue gum's winter flowering sits on that same calendar, and long-term monitoring of exactly this habitat — Pink Gum–Blue Gum woodland in the Mount Lofty Ranges — has found more than half its bird species in decline, a slow-motion 'extinction debt' still being paid from historical clearing (Szabo et al. 2011). A lone flowering blue gum in a paddock is that fragile calendar reduced to one tree, not a birds' sole nesting site or their only possible nectar plant.