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We do not know whether the availability of food plants is the primary factor enabling Angulate Tortoises to inhabit a wide variety of habitats along the southern and western coasts of South Africa. Here we used focal observations to study the diet of Angulate Tortoises over four seasons at two distinct sites in the southwestern Cape, the West Coast National Park (WCNP), and Dassen Island (DI). Seasonal fluctuations in temperature, rainfall, and food plant availability influenced the activity pattern and feeding activity of Angulate Tortoises. Tortoises were more active during the wet season, winter and spring, than during the dry season, summer and autumn. Diet differed between sites and among seasons. WCNP tortoises had a diverse diet of grasses, shrubs, herbs, and succulents, whereas DI tortoises ate mostly herbaceous plants. DI tortoises had few dietary choices available compared to choices available to WCNP tortoises. At both sites, herbs and seedlings were important diet components during the wet season. The dry season diet consisted largely of dry plant material. Angulate Tortoises on DI supplemented their intake of dry plant material with rabbit feces, which comprised more than 27% of the diet in summer and autumn. The opportunistic feeding behavior of Angulate Tortoises helps explain their distribution among a wide variety of habitats. Their persistence in disturbed areas is probably determined by the abundance of easily digestible, herbaceous plants during the wet season and the tortoises’ low activity and low metabolic demands during unfavorable periods.