Kookaburra digging up grubs

This Laughing Kookaburra was digging insects (eg what appears to be a beetle grub) from the mulch at the base of a tree in the small coastal town of Yorkeys Knob, just north of Cairns, Queensland (22 April 2012). I think it may be a female; the brighter male was patiently keeping watch in the low branches of the tree above, before coming for a feed himself after she flew towards us.