Estimating wildlife abundance across Victoria

To manage animal populations, it is important to understand how many animals there are and where they are in the landscape. When considering a large area, such as the whole of Victoria, this can be a very difficult task, and counting every animal is not feasible. When a species is rare or hard to detect, this can be even more complicated.

To address these challenges, ARI researchers use population models to estimate the number of animals across large areas. They use carefully designed surveys to count animals through portions of the whole area of interest. Using these samples, researchers can then create statistical models that relate the animal counts to environmental factors that affect animal population numbers, such as climate, food and shelter. The resulting statistical models are then used to estimate animal numbers in areas that were not directly surveyed, allowing animal numbers to be assessed across large areas.

Another consideration is the difficulty of accurately counting the animals in the first place. For many reasons, such as dense bush or difficult terrain, it is unlikely all animals that are present in a survey area will be seen and counted. To overcome this, ARI researchers use a variety of methods to better assess the number of animals that are actually present, such as double observer counts or distance sampling.

Population modelling continues to be a critical part of wildlife management worldwide. Using the latest peer-reviewed methods, ARI can estimate population numbers to inform resource managers and measure confidence of model predictions.