Tagging of Atlantic cod with different sizes of Thelmabiotel acoustic tags, in the Horns Rev 2 offshore windmill farm in the southern North Sea (Denmark) approx. 35 nautical miles northwest of the Danish port Esbjerg. The windfarm is owned and operated by energy provider Ørsted (Orsted). The windfarm covers an area of 35 km2 and consists of 91 2.3 MW windmills placed upon monopiles. The area is dominated exclusively by sandy bottom and varies in depth: 7-15 meters. 30 hydrophones (Thelmabiotel) have been placed inside the windfarm area, this was done in august 2023. The aim of the project is to catch and tag a 100 cod in two size classes 30-40 cm and 40< (combination unknown). The tagging will be executed in the fall and winter of 2023.