The Changing Role of Shrubs in Rangeland-Based Livestock Production Systems: Can Shrubs Increase Our Forage Supply?

Abstract

In the past 50 years, cattle, sheep, and goat num- bers have increased from about 2.3 billion animals in 1961 to 3.4 billion in 2010,1 and are projected 2 to reach nearly 4.2 billion animals by 2030. Three continents (Africa, Asia, and South America) experienced a cumulative increase of nearly a billion ruminants during the past three decades.1 Projections suggest that by 2030, ruminant livestock numbers in developing countries will exceed those on the entire planet in 2000.3 The world’s goat population has nearly doubled in the past three de- cades, from ~474 million in 1981 to ~910 million in 2010, with much of this growth in Asia and Africa.1 Increased demand for red meat is driven by population growth, ur- banization, and improved economies (especially Asia), a trend projected to continue through 2030.2,4 Rural/peri- urban small-farm growth in places such as sub-Saharan Africa has also contributed to rising numbers of small ru- minants.

DOI: 10.2458/azu_rangelands_v36i2_estell