In their recent paper, de Leeuw and Tothill (1990) discussed the shortcomings of estimating carrying capacity (CC) of pastoral systems in Africa. They noted the difficulty of determining available forage per animal due to high annual and spatial variability in plant production, seasonal changes in forage quantity and quality, livestock species mix, and the use of supplemental feeds.

This document contains a collection of critical comments by experts working in the field of pastoralism with regard to several PDN papers.

Grazing reserves in Nigeria are areas set aside for the use of pastoralists and are intended to be the foci of livestock development. The stated purpose of grazing reserves is the settlement of nomadic pastoralists they offer security of tenure as an inducement to sedentarization through the provision of land for grazing and permanent water. This paper reviews problems associated with grazing reserves and offers suggestions to make them more productive and relevant to the needs of the intended beneficiaries.

Summarises past and present experiences with livestock performance testing in sub-Saharan Africa and outlines the role of networks in improving on-farm testing through the use of standardised testing methods and rapid data handling and feedback. Includes data on the distribution of cattle and sheep populations by ecological zone in sub-Saharan Africa. Presents current programmes for on-farm and on-station performance recording.

It is clear from the failure of our efforts in many countries to halt the desertification process - deserts are now advancing at a rate of nearly 15,000,000 acres a year worldwide (Worrall 1984) (that something was missing in our knowledge of the problem). Four discoveries have been made that enabled us to design a simple holistic model to manage resources successfully in a sustained and economic manner.