Fig. 5: The number of individuals encountered per 100 km in protected versus unprotected areas, as an index of each species’ dependence on PAs.
Index values potentially ranged from +1.0 (recorded only within PAs) to −1.0 (recorded only in UPAs). a, Boxplot showing PA dependency scores in relation to survey period (green, 1969–1995; blue, 2000–2020) and body size class. In each period, large raptors were significantly more dependent on PAs than small–medium species. Notably, for species in both size classes, PA dependency increased significantly between 1969–1995 and 2000–2020. Boxplots show the median, first and third quartiles. Whiskers extend to ±1.5Ă— the interquartile range. Each point represents one species; n = 15 large, 27 small–medium. b, Scatterplot showing annual change in abundance vs change in dependency on protected areas.The extent to which a species’ dependence on PAs changed between the two periods was significantly correlated with change in abundance. Species whose encounter rates had declined sharply had become more dependent on PAs than those showing a moderate decline or increase. Each point represents one species (n = 42); the fitted line and shading show modelled change rates ±1 s.e.m. (model 16 in Extended Data Table 1).
