Reintroductions have been increasingly used for species restoration and it seems that this conservation tool is going to be more used in the future. Nevertheless, there is not a clear consensus about the better procedure for that, consequently a better knowledge of how to optimize this kind of management is needed. Here the dynamics of released long-lived bird populations in object-oriented simulated reintroduction programs is examined.

Sharks, rays, skates and chimaeras play an important role as predators in the ecosystems. These species could serve as potential sentinels for the presence of xenobiotics in marine ecosystems. In this study, liver carboxylesterase activity was determined for 20 species of chondrichthyans. Carboxylesterase activity is involved in the metabolism of pesticides, lipids and certain drugs, suggesting that this enzyme could contribute to species-specific differences in drug detoxification.

Many threatened species in Europe have been expanding their distributions during recent decades owing to protection measures. Range expansion has come about via two processes, natural expansion from existing range and reintroductions to new ranges. Reintroductions may prove to be a better way to establish populations because individuals are less subject to competitive relationships lowering breeding success than individuals expanding from existing populations. Whether this is true, however,...

Assessments of amphibian immune state have been commonly made through indirect methods like phytohemagglutinin injections, or by direct methods like cell counts from blood smears. Here a simple method is validated to assess immune responses in amphibians by means of flow cytometry with a fluorescent lipophilic dye, which removes the need for specific antibodies.

Most mammals rely upon scent for intraspecific communication. As most bear species have large home ranges and are non-territorial, scent deposit while walking could be an effective way to communicate with conspecifics. Here, the existence of pedal glands in brown bears and their role in chemical communication are investigated from a histological, biochemical and behavioural perspective.