1. Australia's Cattle Count and Why It Can't Be Compared Directly with Kangaroos
According to the Australian Bureau of Statistics (ABS), there were 29.7 million cattle as of June 30, 2025. This was a 2.5% decrease from the previous year [1]. On the other hand, the South Australian management plan reports that in 2023, kangaroos in managed capture areas across five states (Queensland, New South Wales, Victoria, South Australia, and Western Australia) exceeded 35 million [3]. Dividing 35 by 29.7 shows kangaroos are about 20% more numerous, but the difference is not huge. It is important to remember that the kangaroo number is from three years prior, while the human population was 27.9 million as of March 2026 [9]. Crucially, the 35 million figure is not the total number of kangaroos in the entire country. It is an estimate for specific species in surveyed areas within those five states where commercial capture is managed [3]. Placing these two numbers side by side can make it seem like they measure the same thing, but they do not.
2. How Cattle on Farms Are Counted Each Year
Cattle are easier to count because they have owners and stay in fixed locations like farms. The ABS estimates the number of cattle as of June 30 each year using multiple data sources [1]. These statistics are sometimes revised later. For example, the June 2024 cattle count was initially reported as about 30.4 million but was corrected to about 30.48 million in the next year’s version [1]. Additionally, starting with the 2022-23 data, the ABS began including cattle from smaller farms in the new dataset. This means older figures, such as those in the 24 million range, cannot be directly compared with newer ones [1]. The Meat and Livestock Australia (MLA) organization predicts that the national herd will stabilize at about 31 million in its September 2025 outlook [2]. However, the MLA figure is a prediction, while the ABS figure is a measurement as of the end of June. They should not be placed in the same column as if they are the same type of data.
3. How Wild Kangaroos Are Counted from Planes Along Set Lines
Unlike cattle, wild animals in open fields cannot be recorded one by one. In New South Wales, trained surveyors fly in planes at low altitude and count kangaroos along predetermined survey lines [4]. The type of aircraft depends on the terrain. Small helicopters are used for hilly highlands, while fixed-wing planes are used for the flat western plains [4]. The frequency of surveys also differs: the western plains are surveyed every year, while highlands are surveyed every three years [4]. There are specific rules about which animals are counted. Commercial capture targets four species: the Red Kangaroo, Western Grey, Eastern Grey, and Common Wallaroo (Euro). In New South Wales, the Red, Western Grey, and Eastern Grey kangaroos make up about 97% of the capture [5]. In 2024, the estimated number of these four species in managed areas of New South Wales was 13.9 million [4]. In the western plains alone, there were about 5.02 million Red Kangaroos and about 4.25 million grey kangaroos [4].
4. Why Aerial Surveys Miss Some Kangaroos and Need Revising
Aerial surveys are prone to missing animals, and counts are thought to tend toward being lower than reality [6]. A study in Victoria found that estimates using thermal imaging cameras were about 30% higher than estimates made by observers. The difference was largest in forests [6]. However, this result comes from one study in one state. It is not certain that a 30% difference would appear in other places. Numbers also change when data is re-examined. In Victoria’s 2024 report, the estimated number of grey kangaroos in the state was revised from 2.36 million to 2.23 million based on a 2022 survey. The annual capture quota also dropped from 156,000 to 142,000 [8]. This is a decrease of about 6% in the estimate and about 9% in the quota. Therefore, kangaroo numbers are affected by both missed sightings and revisions. Because of this, it is not possible to compare them with cattle using the same standard to decide which is more numerous.
5. How Rainfall and Drought Change Kangaroo Numbers
Wild kangaroo numbers change significantly with rainfall. A 1984 paper summarizing aerial surveys in western New South Wales reported that kangaroos nearly doubled between 1975-76 and 1982. However, a widespread drought in 1982 caused an average decrease of about 43% [7]. It is said that there is a delay of about six months between rainfall and changes in population numbers [7]. This story is from one region in the 1980s and does not necessarily apply to the whole country today. However, the impact of drought is still seen in capture quotas. In northern New South Wales, the capture quota was lowered from 15% to 10% of the estimated population due to declines, then returned to 15% in 2025 [4]. Western Australia also reduced the proportion of Red Kangaroos in the central region from 15% to 10% in 2024 due to drought [10]. Thus, kangaroo numbers are not fixed at "about 30 million" like cattle; they fluctuate depending on rain.
6. Try Counting Birds Along a Set Route in Your Town
Counting along a set line under set conditions is the core idea of aerial surveys. You can try this on a short road near your home. For example, walk the same road at the same time every day and write down the number of birds you see. Using the same road helps you see how weather or time of day affects the count. Since you might miss some birds, you can count the same spot three times to see the variation in numbers. Walk the same road at the same time on different days and compare the counts to realize that "numbers change even on the same road." When walking, watch out for cars and tell a family member where you are going.