Routes are sampled once per year during the height of the breeding season. This is primarily June for most of the BBS sampling area. However in the extreme southern US (e.g. Florida, southern Georgia, southern Alabama, etc.) and desert regions of the Southwestern US, routes can be sampled in May. If uncertain check with your local or national BBS coordinator. In the Canadian territories and northern regions of Canadian provinces, routes may be sampled as late as July 7.