30 July 2023

Barn Owl 2023 update

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.

So whilst we still have some siets to check, the totals so far are 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
126
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 90 132 119 177 133 189 191
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.


Once we've visited the last couple of late sites we'll update the table to a final version for the year and maybe even see over 200 chcisk ringed for the first time!

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