We are developing an online catalog/database of all arthropod collections in the world https://bug-collections.org . It grew out of several NSF-ADBC Thematic Collections Networks created in the last 10 years (Cobb et al, 2019). It is an extension of our digitization efforts and is driven in part by the overall question- “Do we have enough specimens to address the full spectrum of key biodiversity issues?”. There are scores of questions embedded in this general question about specific regions, time periods, and taxonomic and/or ecological groups.
We cannot answer this question unless we have basic information about collections, this is especially true for arthropods, since most of the data is based on specimens. Ultimately, we need to fully digitize all collections, but having a collections catalog will greatly help coordinate efforts.
To date we know there are ~223 arthropod collections in North America (Canada, Mexico, and the United States) that house 300 million specimens, not including lots and bulk samples. We estimate that collections are increasing holdings by 1% per year. Based on these estimates, we set a goal of 2,500 specimens per species for the ~170,000 North American species in order to adequately address the spectrum of questions from individual species to global fauna. This means that we need to increase our collecting effort by three-fold (i.e., 3% per year increase in holdings) to have enough specimen data unless we can coordinate more among collections. We cannot coordinate without having basic knowledge about collections.
We further estimate there are ~750 collections outside of North America, which means the current estimate for the total amount of arthropod specimens in arthropod collections in the world is one billion. If North American collections are representative and the estimates for number of extant arthropod species range from 1.5 to 7 million (Stork, 2018), then we currently only have 144-672 specimens per species. So even if we digitized them all we would fall far short of what we need. But these are still mostly fluffy estimates, we will know more when we complete the task of obtaining basic information about all collections.
Another result from our assessment of North American collections was that the even collections with more of a global focus (e.g., Smithsonian) were the most important collections in inventorying the regional arthropod fauna. So, having a small regional collection can be extremely important in providing data for an area at least within a radius of 100 km. The lack of physical collections typically means a region is poorly inventoried (e.g., northern Canada, northwestern Mexico, Nevada). Knowing where collections exist will allow us to either work towards creating new collections and/or coordinate efforts among existing collections to inventory under-sampled regions.
The work required to address the basic question posed above is monumental. For the World Index of Arthropod Collections to be effective in addressing biodiversity information needs it will be critical that the Catalogue of the World’s Natural History Collections be immensely successful. It needs to define standards for concepts like “collections” and codes as well as provide an overall central repository for all natural history collections. It needs to establish protocols to seamlessly incorporate information from more specialized cataloguing efforts. There has been discussion already about working with herbaria at institutions with no arthropod collection to set up an insect cabinet so they could collect pollinators and herbivorous insects they find on their plant taxa of interest. Vertebrate collections already play a significant role in developing arthropod vertebrate parasite collections. So, it is not just knowing where arthropod collections exist that will help us obtain more arthropod specimens, knowing where all natural history collections are located will help.
There are other efforts that will greatly aid in building and defining the functionality of a Catalogue of the World’s Natural History Collections. These include fishes (A survey of digitized data from U.S. fish collections in the iDigBio data aggregator), Mammals (Mammal collections of the Western Hemisphere: a survey and directory of collections), Mollusks (Mobilizing Mollusks: Status Update on Mollusk Collections in the U.S.A. and Canada).