March Facebook Twitter Whatsapp Google Linkedin Email A sea lamprey that was used for a telemetry research. With geolocators, these fish were followed over time and distance, to find out more about their behavior and the success of their migration into Lake Ijssel. During the Blue Whiting Survey, all caught whiting is sorted, measured and weighed. The catchment area is surveyed on a systematic, predefined cruise track. so the stock of blue whiting (Micromesistius Poutassou) can be mapped in the best possible way by the researchers. Various land-based studies show that wind turbines can cause fatalities among bats, in particular during migration. Wageningen Marine Research is conducting a study on behalf of the Dutch Ministry of Economic Affairs and the Dutch Ministry of Infrastructure & Environment to access the fatality risk of bats at offshore wind turbines, as various species of bats also migrate over sea. The age of fish can be determined by studying their otoliths. Similar to trees, otoliths have annual growth rings. In addition, based on the size of an otolith, the length and weight of the fish can be predicted.