The Pilbara and Kimberley cover approximately 1,000,000 km2, or 40%, of Western Australia’s land mass. There are approximately 150 pastoral leases running an estimated 900,000 head of cattle; about 1/3rd of those in the Pilbara, and 2/3rds in the Kimberley.
The Kimberley has most of the largest pastoral stations and herd sizes in Western Australia due to its relatively reliable rainfall and sustainable native pasture base. It has what we call a tropical monsoon climate – there is a defined wet and dry season.
In comparison, the Pilbara consists of large areas of shrub lands, and receives both summer and winter rainfall, though neither is reliable. It also receives less rain (see the decile map below), as it is what we call a semi-arid climate. This is why there are less cattle in the Pilbara – they need to have a more conservative stocking rate than the Kimberley.