Critical Corridor: Survey of predator occurrence and habitat use in a threatened rainforest protected area: COMATSA-Sud and Marojejy National Park, Madagascar

Madagascar is a nation praised for its floral and faunal endemism and biodiversity. Among the island nation’s most emblematic fauna are its native mammalian carnivores; they are members of the threatened and endemic Eupleridae family. The Corridor of Marojejy – Anjanaharibe Sud – Tsaratanana (COMATSA) is a system of forest protected areas in which three large protected areas are connected in northern Madagascar: Tsaratanana Reserve, Anjanaharibe Sud Special Reserve and Marojejy National Park which is also a UNESCO World Heritage site. COMATSA is a newly protected and currently threatened corridor system that lacks detailed surveys and assessments of its native carnivore community. To identify which terrestrial carnivores and associated fauna occupy the rainforest corridor structure in the boundaries of COMATSA-Sud (southernmost section of COMATSA) and Marojejy National Park, and to identify the effects of forest loss and fragmentation upon their movement and occupancy, we deployed 28 camera stations, 12 single camera stations and 16 double camera stations to document organisms that cross the motion activated camera sensors. From October 20th 2021 to February 10th 2022 (113 days) we collected 1048 unique capture events (all species) and confirmed the presence of four native species in Eupleridae: Cryptoprocta ferox, Fossa fossana, Galidia elegans, and Galidictis fasciata. We also captured one non-native carnivore species: Canis familiaris. These results officially extend the known range of F. fossana and G. fasciata. In our survey, C. ferox and G. elegans were the most common and widespread native carnivores, while F. fossana was the least common. We discuss the negative impacts of forest fragmentation and degradation on native carnivores and highlight the threats posed by the free-ranging non-native carnivore Canis familiaris. This study provides the first detailed survey and occupancy estimates of the carnivore community in the COMATSA-Sud and Marojejy corridor protected area, allowing for comparison with other protected areas in Madagascar. Our findings show that anthropogenic changes to the forest corridor are likely correlated with a biased distribution of carnivore occurrence within the corridor area, as some native carnivores are underrepresented in more disturbed areas. Following our presentation of the data, we provide important management recommendations for protection of the forest corridor and its endemic carnivore community. Primarily we suggest that deforestation and habitat degradation within and around the corridor be halted and that the corridor area be reforested to remedy the forest loss that has already happened. We also suggest that invasive, non-native carnivores be managed or culled to reduce their impact on wildlife, human and ecosystem health