Inventories are exceedingly important.
They provide the permanent, verifiable record of biodiversity. You can have the best bird watcher in the world go out into the field and say, "I saw species x on a certain day at a certain location." Twenty-eight years from now, if that bird watcher is dead, no one that lives in the next generation will know whether that person was really right or not. But if there's a specimen there with specimen label data, this is the only verifiable record we really have for future generations. That's why collections are so important. So these inventories are the foundation for economic, scientific, educational, and conservation activity. When systematists go out and discover these specimens, they will have use decades from now. Thus, scientists discovered much about the effects of DDT by going back into historical records of museums, looking at eggs. We can also discover whether a species was once in an area or whether they've been extirpated from an area, mainly because of specimen records in museums.
We only know about 1.7 million species. From those 1.7 million species, we generate something in the neighborhood of probably, well, recent estimates, if you include all the ecological services, from what we know of those 1.7 is trillions of dollars worth of economic activity. And if we discover the remaining 90 some percent of biodiversity, we would expect to reap many, many more global benefits.
Finally, inventories help build our biodiversity science capacity. Inventories help countries create museums, create jobs. So by undertaking inventory, countries can build their systematic capacity. Inventories must be globally linked. Inventories can target specific geographic areas and they can target selected groups of organisms - birds, insects, marine invertebrates, bats, mammals, whatever. And by interpreting the results of inventories across large scales, you can begin to get an idea of what global biodiversity is like for a particular group.
We don't do, for instance, an inventory of just a protected area. When you do an inventory in a protected area, you have to look beyond it because species and groups of species are not distributed by political boundaries, they're distributed across space. Therefore, you have to link inventories up. If I go in and collect a whole bunch of insects from an area, I don't know whether those insects have been described or not until I go to collections and look at species that are really closely related. So, if I'm looking at beetles, I have to make sure that I look at all the species in that particular genus of beetles to make sure that it hasn't been described before. So you link with all these other inventory efforts around the globe.