The Betsileo are an ethnic group of rice growers and livestock keepers occupying the south of the highlands of Madagascar. Rice and zebu, Betsileo main staple foods and important gifts for the ancestors, are deeply affected by climate change. Interestingly, from the Betsileo perspective, climate change is not only the result of a bioclimatic process but also the consequence of people’s failure to comply with traditional rules and taboos.

From December 2019, LICCI core team member Vincent Porcher has been conducting research among the Betsileo, an ethnic group occupying the southern part of central Madagascar. Vincent’s research aims to understand the role of wild edible plants collected by children and adults play in Betsileo subsistence food system in a context of climate change. Vincent is conducting research in the Namoly valley, located in the southern part of the Betsileo territory, at the foot of the Andringitra massif at an altitude of 1500m (fig.1). The relief and altitude of this area confer a unique microclimate in Madagascar with a cyclonic tropical season followed by a cold and dry winter (10-14 ° C) then a short off-season. Despite abundant rainfall, frost conditions allow only one rice harvest per year in the region, versus two in the rest of the country. This particularity makes the production of their staple food particularly vulnerable to sudden climate change with greater risks during the lean season.
Data collected during these first months of fieldwork show that the Betsileos perceive many climate-related changes, most often embedded in long chains of complex physical and ecological processes also involving spiritual entities. Among the many observations, the Betsileo systematically mention the drop in rainfall in the wet season, which is their main concern. According to the Betsileo, the decrease in the number of cyclones per year over the past 15 years is the cause of the irrigation problems in the rice fields, as cyclones bring rain. Decreases in rain are accompanied by a shift in the seasons, which profoundly disrupts the agricultural calendar. Delays in rice transplanting due to the lack of water drastically reduces the rice-growing window before the arrival of frosts, which destroy production. The direct consequences are the spread of the lean season and the decrease in annual income.

the Betsileo explain these changes in the climate system as the result of local bioclimatic or ecological processes that feed on each other cyclically (fig.2). For example, deforestation is driven by population increase. But, in turn, deforestation reduces cloud formation, and therefore results in less rains. At the same time, the drier weather limits Betsileo ability to control pasture fires, which destroy the forest.
However, for the Betsileo, this complex system of multiple drivers of climate change is also intertwined with magico-religious processes influencing the climate. The social system of Betsileos is maintained and regulated by many rules and taboos called fady directly connecting to spiritual entities and ancestors. The non-compliance of these taboos has direct consequences which include sudden changes in climate (e.g. hail, lightning and heavy rain). Thus, the Betsileo interpret recent changes in the climate system as the synergy of independent bioclimatic processes and the decadence of their society linked to the loss of ancestral customs.
Understanding Betsileo perceptions of the drivers of climate change is important because this perception affect their adaptation system. Adaptation strategies adopted by Betsileo are often mixed involving technical (i.e. modification of the irrigation system, abandonment of landrace) as well as magico-religious responses (i.e., increase in the number of requests to ancestors, use of specific magic ritual, solicitation of traditional healers-diviners (Ombiasa)).
Thus, for the Betsileos, climate change is a hub in a more complex biocultural mesh.

