The planet’s biological diversity is not evenly distributed; much of the world’s unique life is concentrated in a few specific areas. These regions, known as biodiversity hotspots, represent the most biologically rich terrestrial ecosystems that are also under the most severe threat from human activity. The concept was developed to create a targeted strategy for conservation, prioritizing these areas to safeguard a disproportionately large amount of global biodiversity.
Defining a Biodiversity Hotspot
The designation of a biodiversity hotspot is based on two strict, quantitative criteria established by conservation scientists. A region must first demonstrate a high degree of endemism, meaning it must contain at least 1,500 species of vascular plants found nowhere else on Earth. This requirement ensures the area is an irreplaceable reservoir of unique biological heritage.
The second criterion is a measure of threat, demanding that the region must have lost a minimum of 70% of its original natural vegetation. This threshold signifies that the ecosystem has been reduced to 30% or less of its former extent, indicating an immediate threat to the remaining species. The combination of high endemism and habitat loss forces conservation efforts to concentrate on these areas where the potential for species extinction is highest.
Global Distribution and Key Regions
There are currently 36 recognized biodiversity hotspots scattered across the globe, which collectively cover only about 2.4% of the Earth’s land surface. Despite their small footprint, these regions contain nearly 60% of the world’s plant, bird, mammal, reptile, and amphibian species, a majority of which are endemic. This concentration of life makes their protection an exceptionally efficient strategy for preserving global biodiversity.
Geographically diverse examples illustrate this global distribution, spanning from oceanic islands to vast mountain ranges. The Tropical Andes is the most diverse hotspot on Earth, housing an estimated one-sixth of all plant life, including approximately 15,000 endemic plant species. In Southeast Asia, the Sundaland hotspot, which includes Borneo and Sumatra, is home to the orangutan and a wide array of unique flora. The Mediterranean Basin hosts thousands of endemic plant species adapted to its distinct seasonal climate.
Primary Drivers of Habitat Loss
The intense habitat destruction that qualifies a region as a hotspot is driven by human activities. Agricultural expansion is the single most significant factor, involving the large-scale conversion of native forests and grasslands into monoculture farms or pastureland for livestock. This practice eliminates habitat and fragments the remaining patches, isolating species populations.
Infrastructure development further exacerbates habitat fragmentation, as the construction of new roads, dams, and settlements cuts through natural areas. These developments create barriers to wildlife movement, reduce habitat size, and provide access for logging and mining operations. Resource extraction, such as open-pit mining, directly removes sections of the ecosystem and often contaminates the surrounding soil and water. Climate change also stresses these weakened ecosystems by altering temperature and rainfall patterns and increasing the frequency of extreme weather events.
Conservation Methods and Impact
Conservation efforts in these hotspots focus on land protection and community engagement. Establishing formally protected areas, such as national parks and biological reserves, is a primary strategy that shields intact ecosystems from destructive activities. This process helps secure the largest remaining fragments of natural habitat and prevents further encroachment.
Targeted funding from international organizations provides financial resources for high-impact interventions within these 36 regions. These investments support practical initiatives like the Amazon Region Protected Areas (ARPA) program in Brazil, which helps manage and consolidate vast tracts of rainforest. Community-based conservation programs involve local and Indigenous populations, leveraging their traditional knowledge for sustainable resource management and creating economic incentives for ecosystem preservation.