CUMBIAH: Conservation Union for Management of the Baltic Harbour Porpoise Populations and Their Habitat

Project description

The harbour porpoise is the only native cetacean species in the Baltic Sea, with two distinct populations. The population in the central Baltic Sea now comprises only a few hundred individuals and is critically endangered. To develop effective conservation measures for the highly endangered harbour porpoises of the Baltic Sea, 14 partners from Germany, Denmark, Sweden, Poland, Estonia, Finland and Lithuania have joined forces.
The international research project CUMBIAH is investigating a wide range of research questions in order to develop necessary, efficient conservation measures to be implemented by the partner countries: in particular, the analysis of the latest surveys and calculations of population density and distribution will provide insights into current population numbers and trends. A newly developed method for the acoustic identification of porpoise calves is intended to help determine calving periods and rearing areas. Environmental DNA (eDNA) samples are analysed to assess habitat quality and the presence of prey fish species. Strandings monitoring, carried out in Germany and partner countries, and post-mortem examinations of dead animals provide important insights into the general condition of porpoises, such as age, nutritional status, sex, reproductive status, diseases and causes of death. Furthermore, individuals are genetically assigned to their population of origin and examined for genetic diversity. The genetic data enable population sizes and trends to be estimated. Information on fishing activity and intensity provides insights into the risk of bycatch. Measurements of underwater noise from construction projects or seismic surveys are included in the analysis to identify areas particularly worthy of protection in comparison with porpoise density and distribution.