Access to nest boxes is a fundamental behavioural need for laying hens, who are strongly motivated to find enclosed, private spaces before laying, and inadequate provision causes significant frustration and welfare harm.
Nest box welfare reflects one of the strongest and most well-documented behavioural needs in farmed animals. Pre-laying hens show a highly motivated searching behaviour for appropriate laying sites that cannot be suppressed without causing welfare distress comparable to pain. Hens deprived of nest boxes pace, vocalise, and attempt to lay in corners or under equipment. Welfare science has established that the strength of this motivation justifies treating nest box access as a fundamental welfare requirement. The location, design, and accessibility of nest boxes matters - dark, private, appropriately sized boxes in accessible locations are used preferentially and produce better welfare outcomes than poorly designed alternatives.