Tool 12.13 Assessing total grazing pressure (TGP)
Tool 12.13 Assessing total grazing pressure (TGP)
There are a number of ways of assessing grazing pressure. It is important to factor in the additional DSEs that other species are contributing to your total grazing pressure, so that you are aware of the impact of other grazing species on your country, and avoid any shortfalls that might come about from your calculations.
The glovebox guide to tactical grazing management bases part of this estimate on the different dung that allows different species to be identified. The manual provides a method for estimating the relative grazing pressure of sheep and kangaroos. Based on the comparative levels of dung, an estimate of the kangaroo population (average number for the previous two months) can be obtained if the number of sheep in the paddock is also known. A ‘step – point transect’ process is used to assist in this process. The manual also includes processes for estimating the population of goats based on sightings and rabbits based on active warren entrances.
Grazing pressure can also be determined by conducting:
- Spotlight surveys at night for kangaroos, goats and rabbits.
- Aerial surveys for kangaroos.
Total grazing pressure is determined by attributing a DSE rating to the different species:
- Kangaroo = 0.7 DSE
- Goat = 1 DSE
- Rabbit = 0.1 DSE
For more detailed tables outlining DSEs for different classes of stock, see tool 12.14.
Calculate DSEs for your property
Once the numbers of these animals are determined and the additional grazing pressure is determined, then decision can be made as to whether a control program is required to reduce this additional grazing pressure to a sustainable level. This can be achieved by:
- Rabbit control: baiting, fumigation and warren destruction
- Goat control: mustering, water-point trap yards, shooting programs
- Kangaroo control: obtain a permit for control by a licensed shooter, with meat ideally being used for pet food or human consumption.
