WFVZ: Collections

The WFVZ houses more than four hundred individual collections, totaling more than a million specimens. The Foundation has been a repository for donations of institutional and private collections, resulting in a large number of egg sets and nests in North American museum collections being donated to the WFVZ since the 1970s.

The primary sources for specimens currently are wildlife rehabilitation organizations; car, cat, and window-killed birds; wildlife research agencies and organizations; and the Foundation’s own field research projects. Materials are consistently acquired by the Western Foundation and used by researchers, educators, scientific artists, and other museums. In addition, materials are used in educational tours and presentations for the general public, both at the Foundation and at outside events. All materials are actively maintained to be free of parasites and dust, so that the items can be available for research and education purposes in perpetuity.

If you would like to help us maintain the collections of the WFVZ, see our Volunteer page.  If you are interested in donating specimens to the Western Foundation, please contact us for more information before such a donation. 



WFVZ Collections Eggs

The WFVZ houses approximately 250,000 sets of eggs (equal to more than 1,000,000 individual eggs), representing at least 4,000 bird species from around the world, and collected from more than 400 individual and institutional collections. The egg collection of the WFVZ is the largest in the world.

WFVZ Eggs Willow Ptarmigan

The Western Foundation’s collections have contributed to many scientific fields, such as conservation, ecology, taxonomy, and toxicology. For example, the WFVZ provided photocopies of egg records for more than 500 species, and egg measurements for more than 400 species, covered by Cornell’s “Birds of North America” written and online series. This information and digital pictures of these eggs and nests are now available at Birds of North America.


The Foundation’s egg sets have also figured prominently in studies of eggshell thinning due to contaminants such as DDT and heavy metals. The  WFVZ has contributed data to more than 4,000 studies. Thus, the value of the WFVZ’s collections for science, and for the conservation of bird species, continues to be shown.

Staff of the WFVZ provide data on eggs, including measurements and digital images, to researchers. Please contact René Corado, Collections Manager, for more information, and see our list of services available to researchers.

FVZ collections GuateEggs

WFVZ collections GuateEggs


The Foundation has more than 18,000 specimens from around the world, representing the largest collection of nests in North America and the world.

WFVZ pictures of the nests of North American breeding bird species are available at, or researchers can contact us directly for particular digital images.

WFVZ collections nests brewer

WFVZ collections nests Cliff Swallow

Bird Study Skins

WFVZ Bird Study Skins pats tanagers

The WFVZ houses more than 56,000 study skin specimens representing over 100 countries, with the largest numbers of specimens from the United States (>12,900), Mexico (>12,600), Malaysia (>4,400), Costa Rica (>4,000), and Ecuador (>3,800). The skin collection is at least the 16th largest among North American collections.

Skin loans are made to qualified researchers. Please see our Specimen Loan page, and our List Of Services PDF.

The WFVZ houses more than 4,500 "no-data" teaching specimens (skins, wings, egg sets, and nests) that we loan temporarily to local educators for use in the classroom. Our live-mounts of birds are used primarily during our public tours and tours for school and civic groups. We also have a "teaching kit" available that includes background information on 5 different avian science topics (for middle and high school students), a checklist of the birds of Ventura County, and nest, egg, and study skin specimens. All teaching material loans are free. Contact us for more information. Check our online Databases here WFVZ Collections