It seemed like the birds in this area were on alert the whole day. Noisy miners constantly calling their danger calls. Of more interest (to me, anyway) was a family group of four magpies. Over hours they stood safe sentry on telegraph poles, watching over the reserve, then glide-bombing a tree. I've haven't seen this behaviour before - they would call, then glide like a raptor, then dive into the tree, clacking their strong beaks. One after the other after the other. Finally I twigged that something strange was happening, and followed the noisy miners until I saw this bird of prey (goshawk or sparrowhawk?) burst gracefully from one tree to another close by, then to another, followed by the noisy miners. Hours later, I noticed similar behaviour by the magpies, and again saw the visiting bird glide from one tree to another. I'm wondering if there may have been a pair of these birds, as the alarm call could be heard from two directions at once.