Back from the UK, I collected Chania and Mitzi from kennels. Shortly thereafter, I spotted 11 year old Chania exploring the pergola. All the time we’ve been here, she's never shown any interest in climbing here...until today. However the answer may be very simple. She seems to have noticed that R had put out bird food out...fat balls. Whilst these provide nourishment for birds in Winter, they could also distract the birds from considering threat ...and falling fatally into Chania's clutches. Having said that I don't think there is any real danger...no covering foliage for a stalking cat!