To be able to reach the project goals divers are caught, and equipped with satellite transmitters, on their wintering area within the German Exclusive Economic Zone (EEZ).
The capture takes place from January to April using the night lightning technique. A bigger ship transfers the catching crew and the dinghy, a rigid inflatable boat (RIB), to the catching area where the RIB is launched and the catching crew (4 persons) starts searching for divers. The bigger ship follows the RIB maintaining a distance of approximately two nautical miles for safety reasons but staying far away to prevent scaring of divers.
After divers are successfully caught they are transported to the bigger ship where the veterinarian takes care of the birds. The birds are kept in well ventilated animal transport boxes and cardboard boxes under silent conditions. The surgery procedure is conducted adopting a transmitter implanting technique developed in North America and is performed by experienced licensed veterinarian Julius Morkūnas, DVM from Klaipeda University. The duration from capture to release varies from 7 to 24 hours and the birds are released as close to the capture site as possible. The first field season, in 2015, has shown that this method is ideally suited.