Conservation effectiveness of protected areas for Hong Kong butterflies declines under climate change

Protected areas are important in conserving the rapid decline of biodiversity in the Anthropocene. Yet uncertainty persists whether protected areas will continue to meet conservation goals if climate change causes community or ecosystem shifts. Previous research has proven equivocal with some studies finding protected areas fail conservation objectives and others finding objectives are largely met. The effectiveness of protected area systems within tropical Asia and for insects are particularly under-studied. Using species distribution modeling of 68 butterfly species (15,346 locality records), we carried out an evaluation of the effectiveness of protected areas in Hong Kong, one of the most well-covered (40% land area) protected area systems in the Asian tropics, and projected how the ability to protect biodiversity would change under different climate change scenarios and different conservation target schemes. Under climate change, 15-37% of the modeled species in 2000 were projected to become extirpated by 2050. Under all conservation target schemes, the proportion of species unprotected increased or leveled, by up to as much as 7%. If buffer grids were considered as unprotected, the increase in these gap species was much greater, by up to as much as 22%. These results together indicate that under climate change, the effectiveness of protected areas for butterflies in Hong Kong is likely to decrease despite the territory's relatively high proportion of protected area coverage. We also highlight here the importance of the fortification of partly protected areas in mediating biodiversity loss under the impacts of global change.