Bird nesting success depends on orientation and cavity safety

Data from the LPO (Ligue pour la Protection des Oiseaux) and the Muséum national d’Histoire naturelle indicate that standard mailbox-style birdhouses are more frequently occupied by birds than log-style nesting boxes. In a study of 1,316 nesting sites, approximately 75% were occupied, with the majority being mailbox models. For instance, Great Tits and Blue Tits showed a strong preference for mailbox designs over hollowed logs.

However, experts emphasize that design is less critical than biological requirements. Successful nesting depends on providing a secure cavity of the appropriate size, proper orientation, and timely installation. A common mistake is placing birdhouses facing west or southwest to facilitate viewing from a home's living area. This orientation exposes the entrance to prevailing winds and rain, creating a cold and damp environment that birds will avoid. To ensure occupancy, entrances should ideally face east or southeast to benefit from morning sunlight and protection from the elements.