Monitoring Global Extinction Within an Information Infrastructure

Monitoring extinction events is complex because there is basically insufficient manpower and budget to monitor a large number of species directly through species accounts. Even in those cases it can be hard to be sure the last individual of a species has vanished. There are exceptions of course such as herds of large animals where satellite images can suffice to estimate actual numbers.

In other instances it is possible to monitor indicators such as the amount of forest cover (using remote sensing and GIS systems) and infer from species/area relationships what the status of a particular forest species might be. While there is a bit of debate whether species-area relationships have been used in ways that can overestimate, there is no debate about the species-area relationship itself. And clearly when extinction is the matter of concern any overestimation problem vanishes as habitat shrinks to single digit percentages.