Analysis of GPS trajectories to assess spatio-temporal differences in grazing patterns and land use preferences of domestic livestock in southwestern Madagascar

Abstract

In order to investigate spatial and temporal characteristics of the purely grazing-based livestock husbandry system in southwestern Madagascar, individual animals from 12 cattle and 12 goat herds that were equally distributed across four villages were fitted with GPS tracking collars and their behaviour during pasturing was directly observed to identify seasonal variations in land use and movement patterns along the regional altitude and vegetation gradient. Monitoring occurred at regular intervals of two months over a two-year period to capture inter-annual variability. Herds of both species from the inland limestone plateau covered longer distances and were found further away from their home corrals than those from the coastal plain. Patterns of feeding behaviour and utilization of grazing areas mostly reflected the spatial occurrence of specific land cover classes around the villages and differed significantly between seasons and sites. Seasonal water shortage was one of the key factors affecting dry season livestock movements on the plateau but played a minor role in the coastal plain where livestock keeping proved to be more limited by feed availability. While on transhumance, mobile cattle herds were vulnerable to disadvantages such as limited access to pastureland and water sources nearby their temporary homesteads. The recent problem of armed cattle raids along with emerging land use conflicts compel livestock owners to utilize fewer grazing areas, which threatens to destabilize the region’s animal husbandry system.