It is one of the largest longhorn beetles living in Europe. The beetle is typically associated with old, sun exposed oaks (Quercus sp.) that can be found in open forests, alleys or landscape parks. Females of oviposit eggs into the wood of still living trees in which larvae develop from three to five years. Adults exit the wood through the large oval exit holes (up to 2cm wide); typical signs of the beetles’ presence in the tree. Probably due to its ability to change the characteristics of its host tree and thus provide more favorable conditions for other species, C. cerdo is often considered as an ecosystem engineer.
As many other saproxylic species, however, the great Capricorn beetle has disappeared from a large part of its original distribution. In the Czech Republic, its continuous range has shrunk to the southeast of the country (south Moravia) and only six isolated populations remain in the rest of the republic. The beetle is thus protected under the EU Habitats Directive and classified as vulnerable according to the IUCN Red List of Threatened Species. The reason for its decline in the last century is mainly due to changes in forest management practices resulting in fewer suitable oaks. Potential host trees have become too shaded by surrounding trees and shrubs with an unsuitable age structure. Thus, proper management should focus on creating a sufficient number of suitable trees that are the proper age, and on connecting such localities with the one already inhabited by this species.