Thirty (60%) of the nest boxes on 50 of the CG farms taking part in the project were occupied by Barn Owls – that’s brilliant for the first year!
Eight (29%) of the 28 new boxes were inhabited immediately, which is great news because it normally takes two years for boxes to become homes for the owls.
Successful breeding happened in 23 (76%) of the boxes that were occupied (in two boxes none of the eggs hatched).
A total of 69 Barn Owl chicks were born from 21 boxes across 17 of our farms.
Each pair of owl parents raised between 2-6 chicks (an average of 3.24 chicks per box). This compares well with non-CG farms, which raised an average of 3.20 chicks in long-established nest boxes.
Given the unusually fast take-up of new nest boxes during this first year, we expect that Barn Owl occupancy is likely to rise by 25%in 2012 – leading to 65-70% of our farms having owls in their nest boxes.
If the average breeding rate stays the same, and we assume that around 30% of the occupied boxes will only be used for roosting, we could expect over 100 new chicks on our farms!
Overall, we have achieved the following:
New nest boxes installed and monitored across 15 counties across England.
Excellent occupancy levels, considering half of the farms had new boxes and it normally takes two years for such boxes to become homes for owls.
Quick uptake of boxes by eight Barn Owl pairs – a surprising and rewarding result.
A promising average number of chicks born to owl parents in this first year, which compared favourably with conventional farms.
An anticipated 25% increase in nest box occupancy in 2012 – over 100 chicks on CG farms!