An overview is given of carried out and current field studies, results and gaps with regard to bird damage caused by wind turbines. Present research aims at disturbance of the environment, chances for birds to become victims and actual number of victims. Gaps in our knowledge exist in particular with regard to victims which fall at night. Investigation of the chances for birds to become victims at night is preferable to searching night victims by daylight because of minimal chances of finding them and high labour-intensity. In general it can be said that current field research at the relation between wind turbines and birds is site-oriented. Broader research, especially aimed at the disturbance aspect, is not possible right now, because large wind turbines and wind turbine arrays are rare. 3 figs., 7 refs., 5 tabs.