Renter: Existing cavities. Nests in existing caerial avities (eg beetle emergence holes and dry Rubus stems)(Celary, 1999) and in the pith of dry Rubus stems (Janvier 2012).
Celary & Wisniowski (2001) report that the species will nest in [cavities in] wooden fences, posts and palings, also in the stems of Rubus. D. Genoud (pers. comm 2013) also suspects that nests can be made in the stems of Phragmites australis.