The fauna on show comes from five continents and the specimens are from naturalist correspondents who collected and sent them to the museum, particularly in former Cochinchina, Australia, Mexico, and Réunion. In the 19th century, museum missions were organised in, among others, the Middle East and Caucasia to bring back as-yet-unknown fauna including new types of species, mainly fish and reptiles.
Birds are the group most represented with more than 28,000 specimens, making it the biggest French collection after the Muséum National d’Histoire Naturelle (i.e. French national natural history museum). It is also the only collection outside Paris featuring several tens of types, mainly hummingbirds.
The museum has specimens of extinct species, including a thylacine, a quagga, a couple of huias, etc. and a large number of species that are either rare or bear witness to their historical presence in locations from which they have since disappeared. In addition to their exhibitional and educational interest, many of these animals are used in historical or scientific studies.