Sheep grazing

The Mitchell grass region is the only one in the tropical savannas to graze significant numbers of sheep. The main factor here is that the southern reaches of the Mitchell grass region are the least humid and wet of the savannas. While in the past there were significant numbers of properties grazing sheep south of the Flinders Highway between Mount Isa and Townsville, at present there are very few north of Winton. On average properties grazing sheep are smaller than those grazing cattle, largely because proportionately sheep require an eighth the land of cattle.

Rainfall

Sheep do well on Mitchell grass pasture, particularly in years when rainfall patterns promote additional forb growth between grass tussocks. High protein forbs such as lamb's tongue (Plantago lanceolata) and wild carrot (Daucus carrota) provide a good level of nutrition in such years. In drier years, the sheep can be maintained on the Mitchell grass which provides a maintenance diet while its colour is golden. Its feed value can be downgraded significantly by small falls of winter rain, heavy dews or fogs, or by frosts. After these events Mitchell grass become grey or blackened and may be infested by moulds or smuts.

Production

Sheep production in this region differs significantly from that occurring in more temperate areas. The summer wet season means that feed is available for a relatively short time. Toward the end of the year, before the rains come, protein levels plummet to a level where the sheep may start losing weight. Management of the herd then requires that timing of good feed must coincide with that of greatest nutrient requirements in the sheep lifecycle.

Sheep suffer much more from heat stress than cattle and so shade trees are provided by many enterprises in the region. Lamb losses from attack by dingo, feral cat and fox can be significant in some areas. In addition, kangaroos compete very successfully with sheep for water and pasture.

Three kangaroos eat as much as two sheep and generally select similar kinds of grasses. They confound attempts at managing stocking rates such as spelling or strategic burning because their mobility is not limited by fences.