Vincenzo Penteriani and María del Mar Delgado are both researchers working in animal ecology and behaviour. At present, Vincenzo is a permanent researcher at the Estación Biológica de Doñana, a research centre of the Spanish Council for Scientific Research (CSIC) and María del Mar is a researcher in the Metapopulation Research Group at the University of Helsinki (Finland). They started their research on eagle owls in the '80s. To date, they have worked on this species in several European countries including Italy, France, Spain and Finland. Their eagle owl research projects are regularly funded by the Spanish Ministry of Economy and Competitiveness, the Excellence Projects of the Junta de Andalusia, the Finnish Academy, as well as several National and Regional Parks in Italy and France.