Why biodiversity is declining even as protected areas increase

Why is biodiversity around the world in so much trouble, even though we keep adding new protected areas?  A new paper led by Australian researcher Ro Hill provides a compelling explanation.  Here, Ro summarizes her and her colleagues' key findings:

We’ve expanded the protected area coverage around the globe, to around 15% of the land surface -- with more than a quarter of all countries already exceeding the agreed global target of 17% by 2020.  But biodiversity loss continues apace.

Biodiversity in trouble...

Why?   Our new paper models how this paradox arises in tropical forests, from competition between governance regimes, and makes four important points:

1. The forces that drive forest protection do not necessarily oppose those that drive forest clearance for development. 

The diagram above says it all: we can keep expanding the developed area of the planet AND expanding protected areas as long as there are still some remaining forested habitats.
 
The power of the “develop” and “protect” governance regimes determines the strength of the forces that move the boundaries between areas under protection, areas of remaining forest habitat, and areas under development.

The leaders of the G20 nations recently gave a huge boost to the power of development regimes by promising to invest 60-70 trillion U.S. dollars on new infrastructure projects by the year 2030.  There is no such investment for conservation -- nothing even close!

2.   The power of the “protect” governance regime can actually be lowered as protected areas increase.
 
People may believe that when new protected areas are created, there are more natural areas –- whereas the reality is that every day there are less.  This lowers public concerns about risks from biodiversity loss, decreasing pressure on politicians and weakening the power of the “protect” governance regime.
 
3.  Prioritizing protected area placement by proximity to active agricultural frontiers would make them more effective.

Targets should include both the desired Area under protection AND the absolute limits on Area under development through habitat conversion.

4.  Strengthening the forces that maintain and restore habitat (and oppose its development) is vital to halt biodiversity loss.

This means we must generally favor land-sharing as a conservation strategy rather than land-sparing.  The governance forces that drive land sparing don’t necessarily oppose the governance forces that drive forest clearance for development, so you still get net loss.
 
Hence, strengthening the relative power of land-sharing governance regimes (i.e. those that maintain traditional, sustainable land use, alternative sustainable land use, or restore degraded habitat) is likely, we argue, to have a greater long-term benefit for biodiversity conservation.

Unraveling how governance and power affect biodiversity conservation is a new frontier in conservation science -– but this paper makes an important start and shows where we need to focus our attention.