Why do we lose protected areas?

20 Oct 2015 NUS scientists analyzed factors influencing protected area that are downgrading, downsizing and degazettement in the tropics and sub-tropics.

Larger protected areas (PA) and larger PAs in more densely populated areas are more likely to undergo a PADDD event. Protected area downgrading, downsizing and degazettement (PADDD) is the legal process by which PAs have their level of protection reduced, are made smaller or are removed completely. That larger PAs have a higher probability of PADDD suggest an economic motivation, as larger protected areas take more land away from agriculture than smaller ones, are more costly to circumvent and are more likely to contain exploitable mineral resources. The influence of PA size on the probability of PADDD increases with local population density, indicating the importance of local populations to the future of the global PA estate.

An analysis led by Prof Roman CARRASCO and Mr William SYMES from the Department of Biological Sciences in NUS say their results could be used to inform conservation policy by improving efficiency of resource allocation. They demonstrate a quick and easy way to indentify which PAs in an existing network are less robust to future economic and demographic changes, and consequently may require more resources to function effectively. Their findings are also applicable for the field of systematic conservation planning. They show how future economic and demographic changes can undermine the efficacy of reserve networks if the robustness of the selected sites to these changes is not considered.

The global PA estate is huge and poorly understood system, and more research is needed on how PAs change over time and their findings will stimulate research in this area. They showed significant differences exist in the probability of PADDD between countries and country specific research is required to understand what is driving PADDD at a national level. They hope their paper encourages further research into the mechanisms of PADDD and PA dynamics.


Figure shows the global distribution of PADDD events in their dataset. The gridlines at 40 degrees north and 40 degrees south represent the area of their analysis and the black line represents the equator. [Image credit: William SYMES]



Symes WS, Rao M, Mascia MB, Carrasco LR. “Why do we lose protected areas? Factors influencing protected area downgrading, downsizing and degazettement in the tropics and subtropics.” Global change biology. (2015)