I have plastic ties, which should survive at least 6 months, here in SE-Georgia, USA.
I also have aluminum-foil tape. So I will try that method to prevent landing and depositing.
However, there is still the problem of birds on the antennas higher-up the radio tower ... I suppose I could try the same method there, though I'd need to use non-metallic tape to avoid de-tuning the antenna.
I like our bats and Purple Martins, and other insect-devouring flying critters, so I only want them away from the Davis ...