That is indeed an essential question to get illuminated while also considering the value of a weather station with frequent distortion of data due to bird visits.
Some members have explored the impact of small bird visits on data. Ideally bird visits should be automatically detected and compiled data tagged accordingly.
An additional consideration is that frequent visits of larger birds - a black vulture weighs 1.6 to 3 kg (3.5 to 6.6 lb) - may end up damaging the WF station. For me the option is between the added spikes or relocation of the station.