Journal Article
The Capacity of Australia's Protected‐Area System to Represent Threatened Species
JAMES E.M. WATSON; MEGAN C. EVANS; JOSIE CARWARDINE; RICHARD A. FULLER; LIANA N. JOSEPH; DAN B. SEGAN; MARTIN F.J. TAYLOR; R.J. FENSHAM; HUGH P. POSSINGHAM
Conservation Biology · Vol. 25, Issue 2 · pp. 324-332 · 2011
Abstract
The acquisition or designation of new protected areas is usually based on criteria for representation of different ecosystems or land‐cover classes , and it is unclear how well ‐ threatened species are conserved within protected‐area networks . Here , we assessed how Australia's terrestrial protected‐area system (89 million ha , 11 . 6% of the continent) overlaps with the geographic distributions of threatened species and compared this overlap against a model that randomly placed protected areas across the continent and a spatially efficient model that placed protected areas across the continent to maximize threatened species’ representation within the protected‐area estate . We defined the minimum area needed to conserve each species on the basis of the species’ range size . We found that although the current configuration of protected areas met targets for representation of a given percentage of species’ ranges better than a random selection of areas , 166 (12 . 6%) threatened species occurred entirely outside protected areas and target levels of protection were met for only 259 (19 . 6%) species . Critically endangered species were among those with the least protection; 12 (21 . 1%) species occurred entirely outside protected areas . Reptiles and plants were the most poorly represented taxonomic groups , and amphibians the best represented . Spatial prioritization analyses revealed that an efficient protected‐area system of the same size as the current protected‐area system (11 . 6% of the area of Australia) could meet representation targets for 1272 (93 . 3%) threatened species . Moreover , the results of these prioritization analyses showed that by protecting 17 . 8% of Australia , all threatened species could reach target levels of representation , assuming all current protected areas are retained . Although this amount of area theoretically could be protected , existing land uses and the finite resources available for conservation mean land acquisition may not be possible or even effective for the recovery of threatened species . The optimal use of resources must balance acquisition of new protected areas , where processes that threaten native species are mitigated by the change in ownership or on‐ground management jurisdiction , and management of threatened species inside and outside the existing protected‐area system .