The collection’s database includes over 22000 cataloged lots, of which nearly all are computerized and approximately 70% are georeferenced. The average lot size is 11 individuals, yielding an estimate of over 230,000 cataloged specimens. Approximately 15,000 additional lots exist in an uncataloged backlog, including extensive series of larval fishes from the north Pacific, larval fishes from desert Oregon and the uncataloged portion of the original Oceanography collection. Counting the backlog, the research collection holds approximately 37,000 lots and more than 300,000 individuals.

The collection is comprehensive for freshwater species from Oregon and extensive for North Pacific species. The collection includes more far-flung specimens from Belgium, Brazil, Canada, Costa Rica, The Democratic Republic of Congo, Gabon, Guyana, Hawaii, India, Japan, Lake Baikal, Mexico, Peru, Thailand, Trinidad and Zambia. The collection also holds a rare series of freshwater fishes from Iran, which formed the basis of Neil Armantrout’s doctoral dissertation in 1980 and supported the development of an online identification guide to Iranian fishes. More than 2600 species in 1329 genera and 352 families are represented among the OSIC’s holdings.