It can be overwhelming to think of all of the various conservation efforts that are taking place or still need to take place around the globe. It can be easy to feel lost in thinking where to begin. However professional conservationists handle this much like you and I might handle a long list of chores, errands, or assignments: by prioritizing. When it comes to actionizing efforts in conserving biological resources, professionals make lists determining what should be prioritized and actionized first in relation to the other efforts on the list.
For example, when it comes to conserving biodiversity, this approach would suggest that conservation efforts should be focused on areas with the greatest concentrations of biodiversity and the highest likelihood of losing significant portions of that biodiversity. Do not be mistaken however, this does not mean that areas with less biodiversity and threats should be forgotten. This only suggests that higher diversity areas should receive priority attention when it comes to conservation efforts.
Biodiversity is unlike other environmental threats because a loss of biodiversity is irreversible. Sticking with the idea of biodiversity in conservation prioritization, there are two major approaches to priority settings: classifying areas as either 1. Biodiversity Hotspots or 2. Major Tropical Wilderness Areas.
BIODIVERSITY HOTSPOTS
Biodiversity hotspots consist mainly of exploited and often highly fragmented ecosystems that are greatly reduced in extent. As the title of these areas might give away, biodiversity hotspots exhibit high levels of biodiversity which usually correlates with high levels of endemism. These areas are relatively small, are under high threat, and are classified as less than 25% intact. Given these three characteristics, biodiversity hotspots are seen as areas that need to be rescued rather than preserved.
Biodiversity hotspots are usually identified by two main criteria: 1. Degree of threat and 2. Plant endemism. Plants are used as the principal indicator of biodiversity diversity. Tropical rainforest hotspots showcase high vertebrate diversity and high levels of endemics which corresponds to their global trends of plant diversity. Temperate hotspots are very high in plant diversity and endemism but tend to exhibit much lower vertebrate diversity and endemism.
WILDERNESS AREAS
Wilderness areas emphasize high-biodiversity tropical ecosystems but focus on the opposite end of the threat spectrum in comparison to biodiversity hotspots. Wilderness areas are still largely intact and have low human population density. These areas are relatively large, are under low to high threat, and are classified as more than 75% intact.
Given these three characteristics, wilderness areas are seen as areas that need to be preserved rather than rescued. Wilderness areas are vital in climate stability and are often labeled as storehouses of biodiversity and major watersheds.
While wilderness areas exhibit lower biodiversity levels than biodiversity hotspots, they act as controls against which we can measure the management of the more devastated hotspots.
A common theme between these two prioritization approaches when focusing on biodiversity is that they both analyze the biological parameters and threats posed to these areas. Biodiversity hotspots place a strong emphasis on endemism as the principal criterion for this status.
This is because endemic species are entirely dependent on a single area for survival which makes them the most vulnerable components of any particular community. Since endemic species reside in restricted ranges, if they are confined to highly threatened ecosystems they will be hit first by extinction episodes and are therefore in most need of rapid and effective conservation action.
The academic paper Biodiversity Hotspots and Major Tropical Wilderness Areas: Approaches to Setting Conservation Priorities analyzes the role of biodiversity hotspots and wilderness areas in conservation prioritization. In this piece, the authors identify 24 high-priority terrestrial biodiversity hotspots. Among these 24 hotspots, tropical rainforest systems were found to account for 37.5% total, emphasizing the disproportionately high levels of biodiversity tropical rainforests boast in comparison to other ecosystems.
The remaining natural vegetation in these 24 hotspots covers only about 2% of the land surface on the planet. Of the 124,035 plant species identified in this paper, 45.9% of all plant diversity were endemic and 30-40% of the vertebrates were endemic. These 24 high-priority terrestrial biodiversity hotspots contain no less than 50% of all terrestrial biodiversity in only about 2% of the land surface.
The International Union for Conservation of Nature (IUCN) finds 75% of terrestrial animal species as critically endangered, endangered, or other vulnerable categories within this extremely reduced extent of land.
Prioritization is a tactical and successful approach to achieve conservation efforts, but there are still some social and political obstacles that make it difficult to move forward. This emphasizes the importance of collaboration and bridging certain science and policy gaps to truly and holistically benefit wildlife, the environment, and society.
Once the most important biodiversity hotspots and wilderness areas are determined globally, the next steps in the hierarchy of priority setting can then proceed. This means that once priorities are set at the global level, they can be set at the regional, national, local, and even specific priority site levels.
While I mentioned at the beginning of this article that looking at conservation as a task can be overwhelming, priority setting and international cooperation show how conservation action is quite manageable. In fact, a very high percentage of global terrestrial biodiversity can be protected in a very small portion of Earth’s land surface.
In turn, international efforts to conserve terrestrial biodiversity should focus heavily on these areas, but not exclusively. The methods are there, now there is the need for collaborative actions to ensure as much as possible is conserved.
