The design of artificial nestboxes for the study of secondary hole-nesting birds: A review of methodological inconsistencies and potential biases
The widespread use of artificial nestboxes has led to significant advances in our knowledge of the ecology, behaviour and physiology of cavity nesting birds, especially small passerines. Nestboxes have made it easier to perform routine monitoring and experimental manipulation of eggs or nestlings, and also repeatedly to capture, identify and manipulate the parents. However, when comparing results across study sites the use of nestboxes may also introduce a potentially significant confounding variable in the form of differences in nestbox design amongst studies, such as their physical dimensions, placement height, and the way in which they are constructed and maintained. However, the use of …
Deconstructing incubation behaviour in response to ambient temperature over different timescales
Avian embryos need a stable thermal environment to develop optimally, while incubat-ing females need to allocate time to self-maintenance off the nest. In species with female-only incubation, eggs are exposed to ambient temperatures that usually cool them down during female absences. The lower the ambient temperature the sooner females should return to re-warm the eggs. When incubation constraints ease at increasing ambient temperatures, females respond by increasing either incubation effort or self-maintenance time. These responses are population-dependent even within the same species; but it is uncertain whether they are caused by local environmental conditions or they are an artefact fro…