With over 200,000 specimens, the naturalistic collections of the COL service at IMEDEA represent a significant component of the living and extinct fauna of the Balearic Islands. Among others, we highlight collections of fossil vertebrates, insects, otoliths, crustaceans, and the osteological collection of living vertebrates. Access to these collections is open to both internal researchers and external institutions, including outreach activities, and they can be consulted on GBIF, Taxo&Map, and Pollinators of the Balearic Islands.