After one of the strangest springs weather-wise, the Barn Owl season seemed to be all over the place in 2023. We had regular sites unoccupied, non-breeding birds at some sites and some exceptionally late broods. Even now we have a few sites where we need to revisit to ring chicks!
With some new funding from the FiPL project (Farming in Protected Landscapes) managed by the Cornwall AONB, we are continuing to expand our monitoring, this year onto the Roseland peninsula, with some new ringer recruits this year as well from the National Trust.
Our totals for the year were still quite impressive (note we've knocked off a couple of the early years to make space):
| 2015 | 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | |
| Sites visited | 41 | 47 | 64 | 85 | 87 | 106 | 93 | 112 |
127 |
| Unoccupied | 11 | 12 | 23 | 34 | 36 | 43 | 35 | 34 |
29 |
| Occupied, no breeding | 7 | 8 | 5 | 4 | 3 | 4 | 5 | 4 |
10 |
| Average clutch size (where observed) |
4.6 | 4.6 | 5.3 | 5.2 | 4.7 | 4.6 | 4.5 | 4.5 |
4.6 |
| Average brood size (where observed) |
3.5 | 2.8 | 3.0 | 3.3 | 3.0 | 3.2 | 2.8 | 3.1 | 3.2 |
| Chicks ringed | 70 | 47 | 90 | 132 | 119 | 177 | 133 | 189 | 193 |
| Adults ringed/recaught | 17/8 | 14/9 | 21/14 | 18/14 | 16/15 | 22/17 | 19/17 | 20/22 |
30/24 |
Unsurprisingly there was again some variety in the brood sizes across the area, with the highest average again along the north coast fared the best though (average brood size of 3.7), followed by the east of the county (3.5, compared to just 2.3 last year) and then 3.0-3.1 elsewhere.
There seemed to be more movement between sites this year, with one adult even on its third site in as many years! The movements between bixes (mostly birds ringed as chicks dispersing) are shown here.
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