Blue Wrens: Our Blue Wrens are very active in the garden. A pair of these small cheerful birds nested at least three times in our garden in spring 1999. They raised four fledglings and constantly moving through our garden devouring large numbers of insects. They are very efficient agents of insect control. They chose Grevillea rosmarinifolia as their nest construction sites. Their first nest was constructed in September. No young Blue Wrens appeared from this nest. Instead a Bronze Cuckoo was the result of their labours. The male and female wrens spent a busy three weeks or so feeding this interloper that was twice as big as the parents. Blue Wrens are common throughout eastern Australia. They are about 140 mm long. The males are glossy blue-black on the head, throat and back (see image). The females are mouse-brown with whitish chest.