Too hot to go out we spent some time looking at our house martins on their second broods. We have a selection of boxes including these very heavy woodcrete ones and some very old plastic RSPB ones; they are all in use plus some birds have built on the ledge above and attempted to build adjacent. One year there were 5 nests clustered in these eve but we only have 6 pairs instead of 13 now. 2 of the plastic boxes are being used by wasps but the next door martins take no notice.
