This innovative nest box has been specially designed to maximise the survival chances of chicks in the nest. It does this by making it far more difficult for predators such as cats, pine martens and squirrels to reach into the entrance hole and attack the young. This is made possible by the clever tunnel system and the right aligned entrance hole. As this design requires two turns, small birds such as great tits and nuthatches can freely pass through the hole and proceed through the tunnel into the main nest but larger birds and mammals simply cannot bend and stretch this way. Nest box predation is far more common than you might think with research concluding that up to 20% of nests are affected. The constant loss of young lives and the desire to prevent future loss was the inspiration behind the seattle predator protection nest box. With this design you are therefore greatly increasing the chances of successful fledges.