Jackdaws visit their nesting cavities most days of the year from around Sept 1st until the end of the breeding season in the next year. Presumably they do this because they breed in cavities and these are scarce, at least in our study area. Hence they check daily whether they still own a nesting cavity!

We study the visits the Jackdaws make to the boxes using a small PIR-sensor (PIR = Passive InfraRed) connected to a datalogger. In this way, we hope to answer basic questions regarding the jackdaw behaviour such as whether visit frequency varies systematically between colonies (it appears so) and why, whether visits to different boxes in a colony are synchronized, which would suggest that the colony members move around in flocks outside the breeding season. Other questions pertain to effect of season, time of day and climate on box visitation rates – is it a condition dependent behaviour?

Shown below is the proportion of 12 minute intervals with at least one visit recorded at one box, averaged over a two week period.

Jackdaws visit their boxes most mornings and some afternoons. Rare night time visits are probably a passing owl….