Madagascar’s extraordinary biodiversity: Threats and opportunities

Abstract

Madagascar’s unique biota is heavily affected by human activity and is under intense threat. Here, we review the current state of knowledge on the conservation status of Madagascar’s terrestrial and freshwater biodiversity by presenting data and analyses on documented and predicted species-level conservation statuses, the most prevalent and relevant threats, ex situ collections and programs, and the coverage and comprehensiveness of protected areas. The existing terrestrial protected area network in Madagascar covers 10.4% of its land area and includes at least part of the range of the majority of described native species of vertebrates with known distributions (97.1% of freshwater fishes, amphibians, reptiles, birds, and mammals combined) and plants (67.7%). The overall figures are higher for threatened species (97.7% of threatened vertebrates and 79.6% of threatened plants occurring within at least one protected area). International Union for Conservation of Nature (IUCN) Red List assessments and Bayesian neural network analyses for plants identify overexploitation of biological resources and unsustainable agriculture as the most prominent threats to biodiversity. We highlight five opportunities for action at multiple levels to ensure that conservation and ecological restoration objectives, programs, and activities take account of complex underlying and interacting factors and produce tangible benefits for the biodiversity and people of Madagascar.

Tree canopy density thresholds for improved forests cover estimation in protected areas of Madagascar

“…Madagascar is renowned worldwide for its forest biodiversity but is also grappling with high poverty levels and deforestation rates [1][2][3][4]. Over recent decades, Madagascar's land cover has undergone significant changes, with human activities being the main drivers of deforestation and forest fragmentation [5].…”

“…Despite these challenges, the Government of Madagascar has made significant strides in forest conservation in recent years to safeguard its natural resources and combat deforestation. Over the past two decades, the network of protected areas (PAs) in Madagascar has expanded to cover most of the remaining forests and previously underrepresented ecosystems, including the habitats of threatened endemic flora and fauna species [4,6,7]. Forest monitoring in PAs is crucial in Madagascar as it provides essential information for their management, particularly considering that the majority of the country's natural forests are located within these areas.…”

The effect of a political crisis on performance of community- and state-managed forests in Madagascar

“…Madagascar's government, often with support from international non-governmental organizations (NGOs) have attempted to slow deforestation through the creation of state-managed protected areas. As of 2020, the protected areas system included 110 sites encompassing 10.4% of Madagascar's land area (6.1 million hectares) 30 . From 1990 to 2010, Madagascar's protected areas were found to be effective at reducing deforestation, on average, but performance varied across time and space 31 .…”

Non fire-adapted dry forest of Northwestern Madagascar: escalating and devastating trends revealed by remote-sensing data

“…Particularly the dry forests in NW Madagascar have seen a decrease in patch sizes and distance to non-forest edges more than any other forest types [4,5]. Human-induced fires are the greatest threat to the remaining dry forests of Madagascar, which are highly valued for conservation, community, and research [6]. The western part of the country, where the dry season often lasts over 6 months and people burn forests to expand agricultural and pastoral lands, has seen an average of over 350,000 fires annually between 2012 and 2019 [7].…”

“…As a result, nearly 50% of the remaining dry forests occur within 1 km of fire each year [5,7], indicating the high likelihood of additional fires and a steady increase in the frequency and size of fires in recent years. These fires acutely threaten the fragmented landscape of dry forests in NW Madagascar, highlighting the urgent need for effective wildfire management strategies to protect these valuable ecosystems [6][7][8].…”