Finally, the results of the model predicting the number of animals of each species is also consistent with the results from the multinomial logit choice and conditional net revenue analysis. All species will be hurt by warming and so there will be fewer animals per farm. Beef cattle is especially vulnerable. The net profitability of livestock will be reduced and so farmers will reduce their investments in livestock and shift away from beef cattle.

There has been very little quantitative research on animal husbandry in Africa so there are few empirical studies to compare these results with. A standard Ricardian analysis was done by Seo & Mendelsohn (2006a), using the same data. The results of the standard Ricardian model are quite similar to the results in this paper. That is, the model predicts that net revenues will fall with either rising temperature or rising rainfall levels.

All the AOGCM predictions suggest that African livestock will be damaged as early as 2020. Even small changes in temperature will be sufficient to have a relatively large effect on beef cattle operations. Additional warming is expected to exacerbate these damages. Farmers dependent on beef cattle will be especially hard hit. In contrast, small farms who can switch to sheep or goats may not be as vulnerable to higher temperatures compared to large farms that cannot make this switch. Precipitation also plays an important role in the AOGCM results. Scenarios with less precipitation are less harmful. Because pastures and ecosystems in general are more productive with more rain, this result may seem counterintuitive. However, in Africa, lower precipitation may reduce animal diseases that are quite significant for livestock. Perhaps more importantly, less rain shifts forest ecosystems to savanna or grasslands. These grasslands are more productive for sheep, dairy cattle and beef cattle. Reductions in precipitation from large to moderate levels appear to be beneficial to livestock. As long as there is sufficient precipitation to support grasslands, the livestock will gain.

It is important to note that the economic viability of large livestock operations is more vulnerable to warming, largely because they depend on beef cattle. Although commercial scale livestock operations do well in temperate parts of Africa today, they have few alternatives with warming. Warming will force reductions in beef and dairy cattle, critical to many commercial enterprises. In contrast, small farmers have many substitutes. If it gets warmer, they can shift to heat tolerant animals such as goats and sheep. In these circumstances, small farmers in Africa are actually better able to adapt to climate change than their larger more modern counterparts.

It is interesting to compare the results of this analysis with the Ricardian study of livestock (Seo & Mendelsohn 2006a). This study predicts that large livestock farms will be hurt by warming but that small farms will in fact gain. These qualitative results are also supported in this paper. The Ricardian study predicts a range of expected income effects from climate change depending on how the model is estimated. The structural results are in the middle of this range. The structural results are different but consistent with the more traditional Ricardian model predictions.

This analysis reveals that farmers will most likely adapt to climate change. It suggests that farmers will switch species and move away from cattle and towards goats and sheep. Small farmers will be able to make these changes without much change in expected income. However, these changes are predicted to reduce the net incomes of large farms considerably. African policy makers must be careful to encourage private adaptation during this period of change. There may be nothing that can be done to sustain the large cattle operations that depend on current climate.

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