Back at the end of November 2016, I wrote about the Bird Defences Stage 1, unfortunately, I hit a snag.
I noticed yesterday that one of the spike strips was missing, on closer inspection, a couple of others were also loose at one end.
Turns out the double sided foam tape is not a good idea! Although it adheres perfectly to the metal frames of the window, the side exposed to the bird strips (and the sun) simply lost all adhesion and detached from the spike strip.
Today, I went round them all, removed them, scraped the foam strip off the window frame with a knife and then re-attached them all with clear silicone.
I had started the Stage 2 defences (more to come soon) and had been using silicone for this and it appears to be a much better bond. Running a bead of silicone down the length of the spike strip and then pressing firmly along the length to get a good spread.
Hopefully that is the problem solved...