Since the 1950s, humans have changed ecosystems more than during any other similar span in history, causing staggering losses of biodiversity. Informed policy is urgently required to slow these losses, but is hampered by the lack of a consistent scientific framework for tracking the conservation status of Earth’s ecosystems, and of objective and transparent criteria for identifying those more likely to disappear. Recognizing this major scientific gap, the IV IUCN World Conservation Congress (Barcelona, Spain, 5-14 October, 2008) set in motion a process to develop risk assessment criteria that will eventually lead to a new tool for conservation policy: a global IUCN Red List of Ecosystems.

 

Siete Tazas National Park, Chile. © Gonzalo Medina

Crops and paramos. © Giuseppe Colonnello

 

Red lists of species are a highly successful model for translating science into conservation policy and action, from global to local scales: the Convention on Biological Diversity uses red list indices to track progress towards its 2010 biodiversity target, and local species red lists inform national conservation policy in over 100 countries.

 

Torres del Paine National Park, Chile. © Jennifer Romero

 Caroni River. © Pedro Uviedo

 

For large-scale conservation planning, ecosystem status may be better than individual species’ status as an indicator of biodiversity as a whole. Moreover, society often perceives the problems of biodiversity loss most acutely not at the species level but at the ecosystem level, through the loss of services such as clean water, food, timber, fuel and recreation. As biodiversity observation networks continue to expand, the data required for global assessments of ecosystem status have become more readily available and integrated. Finally, in urgent situations, since they may be conducted with remotely-sensed data, ecosystem-level assessments may be more rapid than species-by-species assessments: despite decades of effort, by 2010 only 55,926 of the 1,727,708 known species of the world (< 3%) had been evaluated for the IUCN Red List of Threatened Species.