Pre-Contact Population Estimates & Ecological Carrying Capacity Across The Bibbullmun Nation

1. Colonial Demographic Minimisation vs. Forensic Reconstruction

A central pillar of the British Crown's assertion of terra nullius in 1829 was the deliberate numerical minimisation of the Indigenous population inhabiting the South West of Western Australia.^[1] Early colonial administrators, led by Lieutenant-Governor James Stirling, promulgated speculative figures suggesting that the entire Bibbullmun region was occupied by merely a few thousand dispersed 'nomads'.^[1][4] Anthropologist A.R. Radcliffe-Brown later entrenched this colonial bias by estimating the pre-contact South West population at between 3,000 and 6,000 individuals.^[3]

Modern ethnohistorical and archaeological research has completely discredited these colonial undercounts.^[1][2] Forensic demographic analysis conducted by Sylvia Hallam demonstrates that the Southwest was home to an estimated 12,000 to 20,000 people prior to the catastrophic introduction of European pathogens (smallpox, influenza, and measles) in the late eighteenth and early nineteenth centuries.^[1][6] This dense population was structured into fourteen regional subnations and hundreds of localised kalla (hearth-fire) estates, maintaining continuous territorial jurisdiction across 200,000 square kilometres.^[1][5]

2. Ecological Carrying Capacity and Anthropogenic Landscape Engineering

The substantial carrying capacity of the Bibbullmun territory was not an accidental bounty of untouched nature, but the direct product of thousands of years of sophisticated ecological engineering.^[1][2] The Bibbullmun people practiced what modern historical ecologists term 'Human Niche Construction', systematically modifying vegetative structures and animal habitats to dramatically amplify productivity.^[1]

Foremost among these systems was the application of fire-stick farming (kalla-boodja burning), conducted during the dry summer seasons (Birak and Djeran).^[1][4] By applying localised, cool-mosaic burns across grasslands and open eucalyptus woodlands, custodians:
- Prevented devastating canopy conflagrations;
- Stimulated fresh green shoots that attracted large macropods (yonga and koomal) into predictable hunting reserves; and
- Promoted the mass germination of edible tubers, particularly the native yam (Dioscorea hastifolia / warrine) and orchid bulbs.^[1][2]

Along the extensive coastal wetlands of the Swan and Peel regions, Bibbullmun women managed vast beds of bulrush (Typha domingensis / yanjet).^[2][7] Ethnobotanical calculations show that a single hectare of managed yanjet wetland could yield millions of calories of carbohydrate-rich rhizomes, supporting seasonal aggregations of hundreds of people during inter-tribal assemblies without depleting local reserves.^[1][2]

3. Marine and Estuarine Harvesting: The Mungah Infrastructure

The carrying capacity of coastal Bibbullmun estates was further magnified by sophisticated hydraulic civil engineering.^[2][7] Across estuaries such as Oyster Harbour at Minang / Albany and the Peel-Harvey inlet at Bindjareb, custodians constructed extensive stone and brushwood fish weirs (mungah).^[4][7]

Accounts by Scott Nind at King George Sound describe permanent tidal stone traps designed with calibrated channels that allowed small juvenile fish to escape into the open ocean while trapping adult salmon, mullet, and bream on the falling tide.^[7] During seasonal fish runs in autumn (Djeran), these installations captured metric tons of protein in a single tide, enabling regional clans to host diplomatic and ceremonial assemblies (corroborees) lasting several weeks.^[4][7]

4. Rebutting Terra Nullius through Demographic Density

The forensic reality of Bibbullmun demographic density delivers a fatal empirical blow to the legal justification of British colonisation.^[1][5] Under classical international law derived from the law of nations (Vattel and Grotius), the doctrine of occupatio was strictly limited to lands that were genuinely uncultivated and uninhibited by settled political communities.^[1]

The presence of up to 20,000 people, organised into clearly demarcated estates with managed boundaries, permanent hydraulic fish traps, and engineered plant corridors, constituted undeniable evidence of sovereign possession.^[1][4] The British decision to declare Bibbullmun territory terra nullius in 1829 was not based on empirical observation, but on an intentional, fraudulent erasure of demographic reality designed to seize valuable agricultural land without payment, treaty, or compensation.^[1][5]