Winter Wren (with the amusing Latin name troglodytes troglodytes) sometimes roosts communally when cold weather hits. Although unusual, roosting groups can be large; more than 30 wrens were found in one nest in Washington State, USA.
Found in south-east Queensland, south to Tasmania, across Victoria to the Eyre Peninsula in South Australia. Generally within 200 kms from the coast. Also up the Murray River and Lachlan River in New South Wales.