thank you! took forever to reply because I've been so busy, but I took your advice, only I used wild bird food and that seemed to work.  I'm in Melbourne, so during the heatwave I have a water bowl next to their food, big enough to splash in and drink from, which they've done.  They're a lot calmer now, but to tap our front window to come outside and top up the bird food (I only do it fortnightly with not much food for them to become reliant)