Feeding behavior of the bamboo lemurs in Maromizaha, Madagascar

Understanding what primates eat and how they find their food helps establish effective conservation strategies, including guiding them in protecting and restoring habitats. This study aims to discover detailed information on the diet and range behavior of Hapalemur griseus, a small-sized lemur commonly found in areas containing bamboo, marshlands, lowlands, and forests. It primarily inhabits primary and secondary forests. I collected data in the Maromizaha Forest in central-eastern Madagascar, a major hotspot for Malagasy biodiversity and lemurs’ conservation. Behavioral data were collected in the field via direct observation for 9 months. The research focused on the types of food eaten by H. griseus. The results emphasized a clear preference for bamboo because tsingolovolo (Megastachya sp) emerged as the most consumed plant across all observed groups. I recorded other food sources. Mushrooms, orchids, soil, and other non-bamboo plants (e.g., ramiringitra, Ficus chyclada) appear to be evenly consumed by conspecifics of the different groups. A particular focus was given to geophagy (voluntary soil ingestion), using the data collected through direct observations and camera trap (CT) images. Indeed, CTs were positioned in specific locations identified as popular sites for soil ingestion. Through these cross-observations, it has been possible to determine the presence of geophagic behavior in H. griseus, highlighting the strong connection between diet and habitat. As bamboo species showed a defense mechanism with a different degree of cyanogenic potential, geophagy may serve as a detoxification strategy, allowing H. griseus to neutralize unpalatable dietary compounds. Nevertheless, H. griseus confirmed itself as a “facultative specialist,” an adaptation that enables this species to be more resilient to environmental changes. Despite its adaptive potential, geophagy suggests a strong link between the species’ dietary behavior and its habitat, highlighting the importance of preserving its natural environment to guarantee long-term survival.