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African rangelands are changing rapidly due to land use change, the erosion of traditional social institutions, and increasing concern about extreme events. These changes pose a challenge to the resilience of pastoral people, their herds, and the rangelands that they inhabit. Despite these changes, debates in academics and policy continue about the optimal herd size to maintain pastoral livelihoods while avoiding environmental degradation. In this study, we draw from 33 focus group discussions with Maasai men and women in northern Tanzania to explore herd size preferences for coping with extreme events. Study participants expressed a preference for larger herds, with the primary rationale being enhanced ability to cope with drought and other extreme events. Those with large herds are better able to sell a few animals, and this money can directly benefit the family and help feed the rest of the herd through purchasing supplemental feed in the form of pumba, crop residues, or access to farmland for grazing crop residues. These findings highlight new pathways and reasons that large herds can be useful. Chief among these is having enough animals to sell to buy supplemental feed and yet sustain a viable herd. Recognizing the cultural importance of livestock to Maasai along with local perspectives on livestock herd numbers will help in supporting culturally relevant adaptation policy and practice. For example, policies and projects could focus on enhancing resilience through facilitating the saving and storing of crop residues or helping maintain livestock prices during extreme events.
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Coupled Demographic Dynamics of Herds and Households Constrain Livestock Population Growth in Pastoral Systems
One of the dominant narratives about pastoral systems is that livestock populations have the potential to grow exponentially and destroy common-pool grazing resources. However, longitudinal, interdisciplinary research has shown that pastoralists are able to sustainably manage common-pool resources and that livestock populations are not growing exponentially. The common explanation for limits on livestock population growth is that reoccurring droughts, diseases, and other disasters keep populations in check. However, we hypothesize that coupled demographic processes at the level of the household also may keep livestock population growth in check. Our hypothesis is that two mechanisms at the herd-household level explain why livestock populations grow much slower in pastoral systems than predicted by conventional Malthusian models. The two mechanisms are: (1) the domestic cycle of the household, and (2) the effects of scale and stochasticity. We developed an agent-based model of a pastoral system to evaluate the hypothesis. The results from our simulations show that the couplings between herd and household do indeed constrain the growth of both human and livestock populations. In particular, the domestic cycle of the household limits herd growth and ultimately constrains the growth of livestock populations. The study shows that the misfortunes that affect individual households every day cumulatively have a major impact on the growth of human and livestock populations.
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- Award ID(s):
- 1946258
- PAR ID:
- 10529206
- Publisher / Repository:
- Human Ecology (Springer)
- Date Published:
- Journal Name:
- Human Ecology
- Volume:
- 51
- Issue:
- 4
- ISSN:
- 0300-7839
- Page Range / eLocation ID:
- 641 to 653
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1007/s10745-023-00431-y
