Microhierax caerulescens.
Wonderful birds! They now seem well settled in their aviary. Like all predators they are very aware of their environment and watching everything that is happening. When a gull flew over their aviary one swivelled its head to watch it passing, another tracked a distant aeroplane over the estuary. They also sometimes flew up to the roof of the aviary and hung upside down briefly - I couldn't work out why.
