Trends in forest cover across protection categories between 2001 and 2009.

Shown are the number of parks experiencing forest loss (Ineffective PAs) and the number of parks experiencing no change or an increase in forest cover (Effective PAs). Values in brackets show the mean area of forests (± standard error; in km2). Ineffective PAs were further divided into parks that lost more than or less than half their forest cover between 2001 and 2009.